Change Unit.multiplier type from decimal to float

Remove remnants related to BigDecimal.

.gitignore

@@ -15,6 +15,9 @@
 /config/master.key
 /config/puma.rb
 
+# Ignore test database.
+/db/test.sqlite3
+
 # Ignore all logfiles and tempfiles.
 /log/*
 /tmp/*
@@ -30,7 +33,7 @@
 
 /tmp/restart.txt
 
-# Ignore user files
+# Ignore user files.
 /.bash_history
 /.byebug_history
 /.config
@@ -38,6 +41,7 @@
 /.lesshst
 /.local
 /.mysql_history
+/.sqlite_history
 /.ssh
 /.vim
 /.viminfo

DESIGN.md

@@ -0,0 +1,59 @@
+DESIGN
+======
+
+Below is a list of design decisions. The justification is to be consulted
+whenever a change is considered, to avoid regressions.
+
+### Data type for DB storage of numeric values (`decimal` vs `float`)
+
+* among database engines supported (by Rails), SQLite offers storage of
+  `decimal` data type with the lowest precision, equal to the precision of
+  `REAL` type (double precision float value, IEEE 754), but in a floating point
+  format,
+    * decimal types in other database engines offer greater precision, but store
+      data in a fixed point format,
+* biology-related values differ by several orders of magnitude; storing them in
+  fixed point format would only make sense if required precision would be
+  greater than that offered by floating point format,
+    * even then, fixed point would mean either bigger memory requirements or
+      worse precision for numbers close to scale limit,
+        * for a fixed point format to use the same 8 bytes of storage as IEEE
+          754, precision would need to be limited to 18 digits (4 bytes/9 digits)
+          and scale approximately half of that - 9,
+    * double precision floating point guarantees 15 digits of precision, which
+      is more than enough for all expected use cases,
+        * if a decimal string with at most 15 significant digits is converted to
+          the IEEE 754 double-precision format, giving a normal number, and then
+          converted back to a decimal string with the same number of digits, the
+          final result should match the original string,
+        * if an IEEE 754 double-precision number is converted to a decimal
+          string with at least 17 significant digits, and then converted back to
+          double-precision representation, the final result must match the
+          original number,
+        * single precision floating point only guarntees 6 digits of precision,
+          which is estimated to be too low for some use cases (e.g. storing
+          latitude/longitude with a resolution grater than 100m),
+* double precision floating point (IEEE 754) is a standard that ensures
+  compatibility with majority of database engines,
+    * the same data format is used internally by Ruby as a `Float`; it
+      guarantees no conversions between storage and computation,
+    * as a standard with hardware implementations ensures both: computing
+      efficiency and hardware/3rd party library compatibility as opposed to Ruby
+      custom `BigDecimal` type,
+    * at present, only normalized numbers are used and considered sufficient, in
+      order to avoid potential issues with the cross-platform compatibility of
+      subnormal (denormal) numbers,
+* in the future, the IEEE 754 decimal64 data type may be considered once it is
+  supported by database engines.
+
+### Database layer vs application layer data model constraints
+
+* database constraints are the final guard against data integrity corruption,
+    * they should safeguard against data referential integrity loss under _all_
+      data (not schema) manipulation scenarios, including application level
+      logic errors and direct data manipulation (e.g. through `dbconsole`),
+* application constraints can be as restrictive as database constraints or more,
+  but not less, as it doesn't serve any use case,
+    * proper application level constraints should prevent unhandled database
+      exception occurences, e.g `ActiveRecord::InvalidForeignKey` for operations
+      performed through Models (i.e. not `#delete_all` etc.)

Gemfile

@@ -1,14 +1,18 @@
 source "https://rubygems.org"
 
 # The requirement for the Ruby version comes from Rails
-gem "rails", "~> 7.2.2"
+# NOTE: after updating Rails make sure that schema dump is not sorted:
+#   v8.1.3/activerecord/lib/active_record/schema_dumper.rb#L195
+# Waiting for this change to be reverted/configuration setting added:
+# https://github.com/rails/rails/pull/56842, https://github.com/rails/rails/pull/55414
+gem "rails", "~> 8.1.3"
 gem "sprockets-rails"
 gem "puma", "~> 6.0"
 gem "sassc-rails"
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
 gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
 
-# TODO: select db gems automatically
+# TODO: select db gems automatically?
 #   database_config = ERB.new(File.read("config/database.yml")).result
 #   YAML.load(database_config, aliases: true).values.map { |env| env["adapter"] }.uniq
 group :mysql, optional: true do

Gemfile.lock

@@ -1,86 +1,89 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    actioncable (7.2.2.1)
+    action_text-trix (2.1.18)
-      actionpack (= 7.2.2.1)
+      railties
-      activesupport (= 7.2.2.1)
+    actioncable (8.1.3)
+      actionpack (= 8.1.3)
+      activesupport (= 8.1.3)
       nio4r (~> 2.0)
       websocket-driver (>= 0.6.1)
       zeitwerk (~> 2.6)
-    actionmailbox (7.2.2.1)
+    actionmailbox (8.1.3)
-      actionpack (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      activejob (= 7.2.2.1)
+      activejob (= 8.1.3)
-      activerecord (= 7.2.2.1)
+      activerecord (= 8.1.3)
-      activestorage (= 7.2.2.1)
+      activestorage (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       mail (>= 2.8.0)
-    actionmailer (7.2.2.1)
+    actionmailer (8.1.3)
-      actionpack (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      actionview (= 7.2.2.1)
+      actionview (= 8.1.3)
-      activejob (= 7.2.2.1)
+      activejob (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       mail (>= 2.8.0)
       rails-dom-testing (~> 2.2)
-    actionpack (7.2.2.1)
+    actionpack (8.1.3)
-      actionview (= 7.2.2.1)
+      actionview (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       nokogiri (>= 1.8.5)
-      racc
+      rack (>= 2.2.4)
-      rack (>= 2.2.4, < 3.2)
       rack-session (>= 1.0.1)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
       useragent (~> 0.16)
-    actiontext (7.2.2.1)
+    actiontext (8.1.3)
-      actionpack (= 7.2.2.1)
+      action_text-trix (~> 2.1.15)
-      activerecord (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      activestorage (= 7.2.2.1)
+      activerecord (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activestorage (= 8.1.3)
+      activesupport (= 8.1.3)
       globalid (>= 0.6.0)
       nokogiri (>= 1.8.5)
-    actionview (7.2.2.1)
+    actionview (8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       builder (~> 3.1)
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
-    activejob (7.2.2.1)
+    activejob (8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       globalid (>= 0.3.6)
-    activemodel (7.2.2.1)
+    activemodel (8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
-    activerecord (7.2.2.1)
+    activerecord (8.1.3)
-      activemodel (= 7.2.2.1)
+      activemodel (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       timeout (>= 0.4.0)
-    activestorage (7.2.2.1)
+    activestorage (8.1.3)
-      actionpack (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      activejob (= 7.2.2.1)
+      activejob (= 8.1.3)
-      activerecord (= 7.2.2.1)
+      activerecord (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       marcel (~> 1.0)
-    activesupport (7.2.2.1)
+    activesupport (8.1.3)
       base64
-      benchmark (>= 0.3)
       bigdecimal
       concurrent-ruby (~> 1.0, >= 1.3.1)
       connection_pool (>= 2.2.5)
       drb
       i18n (>= 1.6, < 2)
+      json
       logger (>= 1.4.2)
       minitest (>= 5.1)
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
-    addressable (2.8.7)
+      uri (>= 0.13.1)
-      public_suffix (>= 2.0.2, < 7.0)
+    addressable (2.9.0)
-    base64 (0.2.0)
+      public_suffix (>= 2.0.2, < 8.0)
-    bcrypt (3.1.20)
+    base64 (0.3.0)
-    benchmark (0.4.0)
+    bcrypt (3.1.22)
-    bigdecimal (3.1.9)
+    bigdecimal (4.1.2)
     bindex (0.8.1)
     builder (3.3.0)
-    byebug (12.0.0)
+    byebug (13.0.0)
+      reline (>= 0.6.0)
     capybara (3.40.0)
       addressable
       matrix
@@ -90,54 +93,61 @@ GEM
       rack-test (>= 0.6.3)
       regexp_parser (>= 1.5, < 3.0)
       xpath (~> 3.2)
-    concurrent-ruby (1.3.5)
+    concurrent-ruby (1.3.6)
-    connection_pool (2.5.2)
+    connection_pool (3.0.2)
     crass (1.0.6)
-    date (3.4.1)
+    date (3.5.1)
-    devise (4.9.4)
+    devise (5.0.3)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
-      railties (>= 4.1.0)
+      railties (>= 7.0)
       responders
       warden (~> 1.2.3)
-    drb (2.2.1)
+    drb (2.2.3)
+    erb (6.0.4)
     erubi (1.13.1)
-    ffi (1.17.2-aarch64-linux-gnu)
+    ffi (1.17.4-aarch64-linux-gnu)
-    ffi (1.17.2-aarch64-linux-musl)
+    ffi (1.17.4-aarch64-linux-musl)
-    ffi (1.17.2-arm-linux-gnu)
+    ffi (1.17.4-arm-linux-gnu)
-    ffi (1.17.2-arm-linux-musl)
+    ffi (1.17.4-arm-linux-musl)
-    ffi (1.17.2-arm64-darwin)
+    ffi (1.17.4-arm64-darwin)
-    ffi (1.17.2-x86_64-darwin)
+    ffi (1.17.4-x86_64-darwin)
-    ffi (1.17.2-x86_64-linux-gnu)
+    ffi (1.17.4-x86_64-linux-gnu)
-    ffi (1.17.2-x86_64-linux-musl)
+    ffi (1.17.4-x86_64-linux-musl)
-    globalid (1.2.1)
+    globalid (1.3.0)
       activesupport (>= 6.1)
-    i18n (1.14.7)
+    i18n (1.14.8)
       concurrent-ruby (~> 1.0)
-    importmap-rails (2.1.0)
+    importmap-rails (2.2.3)
       actionpack (>= 6.0.0)
       activesupport (>= 6.0.0)
       railties (>= 6.0.0)
-    io-console (0.8.0)
+    io-console (0.8.2)
-    irb (1.15.2)
+    irb (1.18.0)
       pp (>= 0.6.0)
+      prism (>= 1.3.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
+    json (2.19.4)
     logger (1.7.0)
-    loofah (2.24.0)
+    loofah (2.25.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
-    mail (2.8.1)
+    mail (2.9.0)
+      logger
       mini_mime (>= 0.1.1)
       net-imap
       net-pop
       net-smtp
-    marcel (1.0.4)
+    marcel (1.1.0)
-    matrix (0.4.2)
+    matrix (0.4.3)
     mini_mime (1.1.5)
-    minitest (5.25.5)
+    minitest (6.0.6)
-    mysql2 (0.5.6)
+      drb (~> 2.0)
-    net-imap (0.5.7)
+      prism (~> 1.5)
+    mysql2 (0.5.7)
+      bigdecimal
+    net-imap (0.6.4)
       date
       net-protocol
     net-pop (0.1.2)
@@ -146,83 +156,93 @@ GEM
       timeout
     net-smtp (0.5.1)
       net-protocol
-    nio4r (2.7.4)
+    nio4r (2.7.5)
-    nokogiri (1.18.8-aarch64-linux-gnu)
+    nokogiri (1.19.3-aarch64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.8-aarch64-linux-musl)
+    nokogiri (1.19.3-aarch64-linux-musl)
       racc (~> 1.4)
-    nokogiri (1.18.8-arm-linux-gnu)
+    nokogiri (1.19.3-arm-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.8-arm-linux-musl)
+    nokogiri (1.19.3-arm-linux-musl)
       racc (~> 1.4)
-    nokogiri (1.18.8-arm64-darwin)
+    nokogiri (1.19.3-arm64-darwin)
       racc (~> 1.4)
-    nokogiri (1.18.8-x86_64-darwin)
+    nokogiri (1.19.3-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.18.8-x86_64-linux-gnu)
+    nokogiri (1.19.3-x86_64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.8-x86_64-linux-musl)
+    nokogiri (1.19.3-x86_64-linux-musl)
       racc (~> 1.4)
     orm_adapter (0.5.0)
-    pg (1.5.9)
+    pg (1.6.3)
-    pp (0.6.2)
+    pg (1.6.3-aarch64-linux)
+    pg (1.6.3-aarch64-linux-musl)
+    pg (1.6.3-arm64-darwin)
+    pg (1.6.3-x86_64-darwin)
+    pg (1.6.3-x86_64-linux)
+    pg (1.6.3-x86_64-linux-musl)
+    pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
-    psych (5.2.3)
+    prism (1.9.0)
+    psych (5.3.1)
       date
       stringio
-    public_suffix (6.0.1)
+    public_suffix (7.0.5)
-    puma (6.6.0)
+    puma (6.6.1)
       nio4r (~> 2.0)
     racc (1.8.1)
-    rack (3.1.13)
+    rack (3.2.6)
-    rack-session (2.1.0)
+    rack-session (2.1.2)
       base64 (>= 0.1.0)
       rack (>= 3.0.0)
     rack-test (2.2.0)
       rack (>= 1.3)
-    rackup (2.2.1)
+    rackup (2.3.1)
       rack (>= 3)
-    rails (7.2.2.1)
+    rails (8.1.3)
-      actioncable (= 7.2.2.1)
+      actioncable (= 8.1.3)
-      actionmailbox (= 7.2.2.1)
+      actionmailbox (= 8.1.3)
-      actionmailer (= 7.2.2.1)
+      actionmailer (= 8.1.3)
-      actionpack (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      actiontext (= 7.2.2.1)
+      actiontext (= 8.1.3)
-      actionview (= 7.2.2.1)
+      actionview (= 8.1.3)
-      activejob (= 7.2.2.1)
+      activejob (= 8.1.3)
-      activemodel (= 7.2.2.1)
+      activemodel (= 8.1.3)
-      activerecord (= 7.2.2.1)
+      activerecord (= 8.1.3)
-      activestorage (= 7.2.2.1)
+      activestorage (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       bundler (>= 1.15.0)
-      railties (= 7.2.2.1)
+      railties (= 8.1.3)
-    rails-dom-testing (2.2.0)
+    rails-dom-testing (2.3.0)
       activesupport (>= 5.0.0)
       minitest
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.6.2)
+    rails-html-sanitizer (1.7.0)
-      loofah (~> 2.21)
+      loofah (~> 2.25)
       nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
-    railties (7.2.2.1)
+    railties (8.1.3)
-      actionpack (= 7.2.2.1)
+      actionpack (= 8.1.3)
-      activesupport (= 7.2.2.1)
+      activesupport (= 8.1.3)
       irb (~> 1.13)
       rackup (>= 1.0.0)
       rake (>= 12.2)
       thor (~> 1.0, >= 1.2.2)
+      tsort (>= 0.2)
       zeitwerk (~> 2.6)
-    rake (13.2.1)
+    rake (13.4.2)
-    rdoc (6.13.1)
+    rdoc (7.2.0)
+      erb
       psych (>= 4.0.0)
-    regexp_parser (2.10.0)
+      tsort
-    reline (0.6.1)
+    regexp_parser (2.12.0)
+    reline (0.6.3)
       io-console (~> 0.5)
-    responders (3.1.1)
+    responders (3.2.0)
-      actionpack (>= 5.2)
+      actionpack (>= 7.0)
-      railties (>= 5.2)
+      railties (>= 7.0)
-    rexml (3.4.1)
+    rexml (3.4.4)
-    rubyzip (2.4.1)
+    rubyzip (3.3.0)
     sassc (2.4.0)
       ffi (~> 1.9)
     sassc-rails (2.1.2)
@@ -232,11 +252,11 @@ GEM
       sprockets-rails
       tilt
     securerandom (0.4.1)
-    selenium-webdriver (4.31.0)
+    selenium-webdriver (4.43.0)
       base64 (~> 0.2)
       logger (~> 1.4)
       rexml (~> 3.2, >= 3.2.5)
-      rubyzip (>= 1.2.2, < 3.0)
+      rubyzip (>= 1.2.2, < 4.0)
       websocket (~> 1.0)
     sprockets (4.2.2)
       concurrent-ruby (~> 1.0)
@@ -246,39 +266,40 @@ GEM
       actionpack (>= 6.1)
       activesupport (>= 6.1)
       sprockets (>= 3.0.0)
-    sqlite3 (2.7.3-aarch64-linux-gnu)
+    sqlite3 (2.9.3-aarch64-linux-gnu)
-    sqlite3 (2.7.3-aarch64-linux-musl)
+    sqlite3 (2.9.3-aarch64-linux-musl)
-    sqlite3 (2.7.3-arm-linux-gnu)
+    sqlite3 (2.9.3-arm-linux-gnu)
-    sqlite3 (2.7.3-arm-linux-musl)
+    sqlite3 (2.9.3-arm-linux-musl)
-    sqlite3 (2.7.3-arm64-darwin)
+    sqlite3 (2.9.3-arm64-darwin)
-    sqlite3 (2.7.3-x86_64-darwin)
+    sqlite3 (2.9.3-x86_64-darwin)
-    sqlite3 (2.7.3-x86_64-linux-gnu)
+    sqlite3 (2.9.3-x86_64-linux-gnu)
-    sqlite3 (2.7.3-x86_64-linux-musl)
+    sqlite3 (2.9.3-x86_64-linux-musl)
-    stringio (3.1.7)
+    stringio (3.2.0)
-    thor (1.3.2)
+    thor (1.5.0)
-    tilt (2.6.0)
+    tilt (2.7.0)
-    timeout (0.4.3)
+    timeout (0.6.1)
-    turbo-rails (2.0.13)
+    tsort (0.2.0)
+    turbo-rails (2.0.23)
       actionpack (>= 7.1.0)
       railties (>= 7.1.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
+    uri (1.1.1)
     useragent (0.16.11)
     warden (1.2.9)
       rack (>= 2.0.9)
-    web-console (4.2.1)
+    web-console (4.3.0)
-      actionview (>= 6.0.0)
+      actionview (>= 8.0.0)
-      activemodel (>= 6.0.0)
       bindex (>= 0.4.0)
-      railties (>= 6.0.0)
+      railties (>= 8.0.0)
     websocket (1.2.11)
-    websocket-driver (0.7.7)
+    websocket-driver (0.8.0)
       base64
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
     xpath (3.2.0)
       nokogiri (~> 1.8)
-    zeitwerk (2.7.2)
+    zeitwerk (2.7.5)
 
 PLATFORMS
   aarch64-linux-gnu
@@ -298,7 +319,7 @@ DEPENDENCIES
   mysql2 (~> 0.5)
   pg (~> 1.5)
   puma (~> 6.0)
-  rails (~> 7.2.2)
+  rails (~> 8.1.3)
   sassc-rails
   selenium-webdriver
   sprockets-rails

README.md

@@ -16,14 +16,10 @@ environment, see the _Contributing_ section below.
 * Server side:
     * Ruby interpreter, depending on the version of Rails used (see _Gemfile_),
         * https://guides.rubyonrails.org/upgrading_ruby_on_rails.html#ruby-versions
-    * database (e.g. MySQL >= 8.0) supporting:
+    * database (e.g. SQLite, MySQL >= 8.0) supporting:
         * recursive Common Table Expressions (CTE) for SELECT/UPDATE/DELETE,
             * MariaDB does not support CTE for UPDATE/DELETE
               (https://jira.mariadb.org/browse/MDEV-18511)
-        * decimal datatype with precision of at least 30,
-            * SQLite3 _flexible typing_ decimal will work, but precision
-              will be limited to 16, making it practical mostly for testing
-              purposes
     * for testing: browser as specified in _Client side_ requirements
 * Client side:
     * browser (e.g. Firefox >= 121) supporting:
@@ -89,14 +85,10 @@ Running
 
 ### Standalone Rails server + Apache proxy
 
-Customize Puma config template:
+Copy and customize Puma config template if required:
 
     cp -a config/puma.rb.dist config/puma.rb
 
-and specify server IP/port, either with `port` or `bind`, e.g.:
-
-    bind 'tcp://0.0.0.0:3000'
-
 #### (option 1) Start server manually
 
     bundle exec rails s -e production
@@ -123,9 +115,10 @@ Contributing
 
 ### Gems
 
-Apart from database adapter, install development and testing gems:
+Install development and testing gems, including at least MySQL and SQLite
+database adapters:
 
-    bundle config --local with mysql development test
+    bundle config --local with development test mysql sqlite
 
 ### Configuration
 
@@ -138,20 +131,29 @@ assets.
 
 ### Database
 
-Grant database user privileges for development and test environments,
+Grant database user privileges for development and test environments. Example
-possibly with different Ruby versions:
+below shows how to grant privileges to all databases which names start with
+`fixinme-` on MySQL:
 
     > mysql -p
     mysql> create user `fixinme-dev`@localhost identified by '<some password>';
     mysql> grant all privileges on `fixinme-%`.* to `fixinme-dev`@localhost;
     mysql> flush privileges;
 
+Dumping development data before database reset:
+
+    mysqldump -h <address> -u <user> -p --no-create-info --no-tablespaces --complete-insert <database> > tmp/data.sql
+
 ### Development environment
 
 Starting application server in development environment:
 
     bundle exec rails s -e development
 
+Accessing database console when more than one test db is present:
+
+    bundle exec rails dbconsole -e test --db sqlite3
+
 For running rake tasks, prepend command with environment:
 
     RAILS_ENV=development bundle exec rails ...
@@ -164,14 +166,22 @@ Tests need to be run from within toplevel application directory:
 
         bundle exec rails test:system
 
-* system test(s) with seed/test name specified:
+* system test(s) with seed or test name specified:
 
-        bundle exec rails test:system --seed 64690 --name test_add_unit
+        bundle exec rails test:system --include test_add_unit --seed 64690
 
-* all tests from one file, with optional seed:
+* all tests from one file, optionally with seed:
 
         bundle exec rails test test/system/users_test.rb --seed 1234
 
+* system tests for selected database configuration (if multiple present):
+
+        bundle exec rails test:system --include /^test_sqlite3_/
+
+* single system test for all database configurations (if multiple present):
+
+        bundle exec rails test:system --include /^test_\\w+_add_unit$/
+
 ### Icons
 
 Pictogrammers Material Design Icons: https://pictogrammers.com/library/mdi/

app/assets/images/pictograms/alert-outline.svg

@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path fill="#ffffff" d="M12,2L1,21H23M12,6L19.53,19H4.47M11,10V14H13V10M11,16V18H13V16" /></svg>
+<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path d="M12,2L1,21H23M12,6L19.53,19H4.47M11,10V14H13V10M11,16V18H13V16" /></svg>

app/assets/images/pictograms/check-circle-outline.svg

@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path fill="#ffffff" d="M12 2C6.5 2 2 6.5 2 12S6.5 22 12 22 22 17.5 22 12 17.5 2 12 2M12 20C7.59 20 4 16.41 4 12S7.59 4 12 4 20 7.59 20 12 16.41 20 12 20M16.59 7.58L10 14.17L7.41 11.59L6 13L10 17L18 9L16.59 7.58Z" /></svg>
+<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path d="M12 2C6.5 2 2 6.5 2 12S6.5 22 12 22 22 17.5 22 12 17.5 2 12 2M12 20C7.59 20 4 16.41 4 12S7.59 4 12 4 20 7.59 20 12 16.41 20 12 20M16.59 7.58L10 14.17L7.41 11.59L6 13L10 17L18 9L16.59 7.58Z" /></svg>

app/assets/images/pictograms/chevron-down.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path d="M7.41,8.58L12,13.17L16.59,8.58L18,10L12,16L6,10L7.41,8.58Z" /></svg>

app/assets/images/pictograms/pencil-outline.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" id="icon" viewBox="0 0 24 24"><path d="M14.06,9L15,9.94L5.92,19H5V18.08L14.06,9M17.66,3C17.41,3 17.15,3.1 16.96,3.29L15.13,5.12L18.88,8.87L20.71,7.04C21.1,6.65 21.1,6 20.71,5.63L18.37,3.29C18.17,3.09 17.92,3 17.66,3M14.06,6.19L3,17.25V21H6.75L17.81,9.94L14.06,6.19Z" /></svg>

app/assets/stylesheets/application.css

@@ -15,6 +15,15 @@
  *= require_self
  */
 
+/* Strive for simplicity:
+ * * style elements/tags only - if possible,
+ * * replace element/tag name with class name - if element has to be styled
+ * differently depending on context (e.g. <form>, <table>, <a> as link/button),
+ * * styles with multiple selectors should have all selectors with same
+ * specificity, to allow proper rule specificity vs order management.
+ *
+ * NOTE: style in a modular way, similar to how CSS @scope would be used,
+ * to make transition easier once @scope is widely available. */
 :root {
   --color-focus-gray: #f3f3f3;
   --color-border-gray: #dddddd;
@@ -46,49 +55,163 @@
 :focus-visible {
   outline: none;
 }
-
+/* NOTE: move to higher priority layer instead of using !important?; add CSS
-
+ * @layer requirements in README */
-/* TODO: collapse gaps around empty rows (`topside`) once possible
+[disabled] {
- * https://github.com/w3c/csswg-drafts/issues/5813 */
+  border-color: var(--color-border-gray) !important;
-body {
+  color: var(--color-border-gray) !important;
-  display: grid;
+  /* NOTE: cannot set cursor when `pointer-events: none`; can be fixed by setting
-  gap: 0.8em;
+   * `cursor` on wrapping element.
-  grid-template-areas:
+  cursor: not-allowed; */
-    "header    header  header"
+  fill: var(--color-border-gray) !important;
-    "nav       nav     nav"
+  pointer-events: none !important;
-    "leftempty topside rightempty"
-    "leftside  main    rightside";
-  grid-template-columns: 1fr auto 1fr;
-  grid-template-rows: repeat(4, auto);
-  font-family: system-ui;
-  margin: 0.4em;
 }
+/* Styles set `display` without distinguishing between [hidden] elements, making
+ * them visible. */
+[hidden] {
+  display: none !important;
+}
+
+
+/* Color coding of input controls' background:
+ *  blue - target for interaction with pointer,
+ *  gray - target for interaction with keyboard,
+ *  red - destructive, non-undoable action.
+ */
+/* TODO: merge selectors using :is() */
+a,
 button,
+details,
 input,
 select,
+summary,
 textarea {
   background-color: inherit;
   font: inherit;
 }
+details,
 input,
 select {
   text-align: inherit;
 }
+input,
+select,
+summary,
+textarea {
+  border: 1px solid var(--color-gray);
+  border-radius: 0.25em;
+  padding: 0.2em 0.4em;
+}
+svg {
+  height: 1.4em;
+  margin: 0 0.2em 0 0;
+  width: 1.4em;
+}
+svg:last-child {
+  margin-right: 0;
+}
+textarea {
+  margin: 0;
+}
+input[type=checkbox] {
+  accent-color: var(--color-blue);
+  appearance: none;
+  -webkit-appearance: none;
+  display: flex;
+  height: 1.1em;
+  margin: 0;
+  padding: 0;
+  width: 1.1em;
+}
+input[type=checkbox]:checked {
+  appearance: checkbox;
+  -webkit-appearance: checkbox;
+}
+/* Hide spin buttons of <input type=number>. */
+/* TODO: add spin buttons inside <input type=number>: before (-) and after (+) input. */
+input[type=number] {
+  appearance: textfield;
+  -moz-appearance: textfield;
+  text-align: end;
+}
+input::-webkit-inner-spin-button {
+  -webkit-appearance: none;
+}
+input::-webkit-outer-spin-button {
+  -webkit-appearance: none;
+  margin: 0;
+}
+/* Text color of table form controls:
+ *  - black for row/table forms,
+ *  - inherited for internal (column specific) buttons/forms. */
+table input,
+table select,
+table summary,
+table textarea {
+  border-color: var(--color-border-gray);
+}
+table input,
+table select,
+table textarea {
+  padding-block: 0.375em;
+}
+table form input,
+table form select,
+table form summary,
+table form textarea {
+  color: inherit;
+}
+table svg:not(:only-child) {
+  height: 1.25em;
+  width: 1.25em;
+}
+input:focus-visible,
+select:focus-visible,
+select:focus-within,
+/* TODO: how to achieve `summary:focus-within` for `::details-content`? */
+summary:focus-visible,
+textarea:focus-visible {
+  accent-color: var(--color-dark-blue);
+  background-color: var(--color-focus-gray);
+  color: black;
+}
+input:hover,
+select:hover,
+summary:hover,
+textarea:hover {
+  border-color: var(--color-blue);
+  outline: 1px solid var(--color-blue);
+}
+select:hover,
+summary:hover {
+  color: black;
+  cursor: pointer;
+}
+/* TODO: style <details>/<summary> focus to match <select> as much as possible.
+summary:focus-visible::before,
+summary:hover::before {
+  background-color: black;
+}
+ */
+input:invalid,
+select:invalid,
+textarea:invalid {
+  border-color: var(--color-red);
+  outline-color: var(--color-red);
+}
 
-
+/* `.button`: button-styled <a>, <button>, <input type=submit>.
-/* blue - target for interaction with pointer */
+ * `.link`: any other <a>.
-/* gray - target for interaction with keyboard */
+ * `.tab`: tab-styled <a>.
-/* TODO: remove non-font-size rems from buttons/inputs below */
+ */
-a,
+.button,
-button,
+.link,
-input[type=submit] {
+.tab {
   cursor: pointer;
   text-decoration: none;
   white-space: nowrap;
 }
 .button,
-button,
-input[type=submit],
 .tab {
   align-items: center;
   color: var(--color-gray);
@@ -96,66 +219,35 @@ input[type=submit],
   fill: var(--color-gray);
   font-weight: bold;
 }
-.button,
+.button {
-button,
+  border: 1px solid var(--color-gray);
-input[type=submit] {
+  border-radius: 0.25em;
   font-size: 0.8rem;
-  padding: 0.4em;
+  padding: 0.6em 0.5em;
   width: fit-content;
 }
-input:not([type=submit]):not([type=checkbox]),
+.link {
-select,
+  color: inherit;
-textarea {
+  text-decoration: underline 1px var(--color-border-gray);
-  padding: 0.2em 0.4em;
+  text-underline-offset: 0.25em;
 }
-.button,
+.auxiliary {
-button,
+  border-color: var(--color-nav-gray);
-input,
+  color: var(--color-nav-gray);
-select,
+  fill: var(--color-nav-gray);
-textarea {
-  border: solid 1px var(--color-gray);
-  border-radius: 0.25em;
 }
-fieldset,
+table .button {
-textarea {
+  border-color: var(--color-border-gray);
-  margin: 0
+  font-weight: normal;
-}
+  height: 100%;
-.button > svg,
-.tab > svg,
-button > svg {
-  height: 1.8em;
-  width: 1.8em;
-}
-.button > svg:not(:last-child),
-.tab > svg:not(:last-child),
-button > svg:not(:last-child) {
-  padding-right: 0.4em;
-}
-fieldset {
   padding: 0.4em;
 }
-legend {
-  color: var(--color-gray);
-  display: flex;
-  gap: 0.4em;
-  width: 100%;
-}
-legend span {
-  align-content: center;
-  flex-grow: 1;
-}
-
-/* TODO: move normal non-button links (<a>:hover/:focus) styling here (i.e.
- * page-wide, top-level) and remove from table.items - as the style should be
- * same everywhere */
 .button:focus-visible,
-button:focus-visible,
+.tab:focus-visible,
-input[type=submit]:focus-visible {
+.tab:hover {
   background-color: var(--color-focus-gray);
 }
-.button:hover,
+.button:hover {
-button:hover,
-input[type=submit]:hover {
   background-color: var(--color-blue);
   border-color: var(--color-blue);
   color: white;
@@ -165,68 +257,41 @@ input[type=submit]:hover {
   background-color: var(--color-red);
   border-color: var(--color-red);
 }
-
+.link:focus-visible {
-input[type=checkbox] {
+  text-decoration-color: var(--color-gray);
-  accent-color: var(--color-blue);
-  appearance: none;
-  -webkit-appearance: none;
-  display: flex;
-  height: 1.1rem;
-  margin: 0;
-  width: 1.1rem;
 }
-input[type=checkbox]:checked {
+.link:hover {
-  appearance: checkbox;
+  color: var(--color-blue);
-  -webkit-appearance: checkbox;
+  text-decoration-color: var(--color-blue);
-}
-/* Hide spin buttons in input number fields */
-input[type=number] {
-  appearance: textfield;
-  -moz-appearance: textfield;
-}
-input::-webkit-inner-spin-button {
-  -webkit-appearance: none;
-}
-input::-webkit-outer-spin-button {
-  -webkit-appearance: none;
-  margin: 0;
-}
-input:hover,
-select:hover,
-textarea:hover {
-  border-color: var(--color-blue);
-  outline: solid 1px var(--color-blue);
-}
-input:invalid,
-select:invalid,
-textarea:invalid {
-  border-color: var(--color-red);
-  outline: solid 1px var(--color-red);
-}
-select:hover {
-  cursor: pointer;
-}
-input:focus-visible,
-select:focus-within,
-select:focus-visible,
-textarea:focus-visible {
-  accent-color: var(--color-dark-blue);
-  background-color: var(--color-focus-gray);
-}
-fieldset,
-input[type=text]:read-only,
-textarea:read-only {
-  border: none;
-  padding-left: 0;
-  padding-right: 0;
 }
 
 
+/* NOTE: collapse gaps around empty rows (`topside`) once possible with
+ * `grid-collapse` property and remove alternative `grid-template-areas`.
+ * https://github.com/w3c/csswg-drafts/issues/5813 */
+body {
+  display: grid;
+  gap: 0.8em;
+  grid-template-areas:
+    "header    header  header"
+    "nav       nav     nav"
+    "leftside  main    rightside";
+  grid-template-columns: 1fr minmax(max-content, 2fr) 1fr;
+  font-family: system-ui;
+  margin: 0.4em;
+}
+body:has(> .topside-area) {
+  grid-template-areas:
+    "header    header  header"
+    "nav       nav     nav"
+    "leftside  topside rightside"
+    "leftside  main    rightside";
+}
+
 header {
   grid-area: header;
 }
 
-
 .navigation {
   display: flex;
   grid-area: nav;
@@ -235,37 +300,31 @@ header {
   margin-inline-start: 4%;
 }
 .navigation > .tab {
-  border-bottom: solid 2px var(--color-nav-gray);
+  border-bottom: 2px solid var(--color-nav-gray);
   flex: 1;
   font-size: 1rem;
   justify-content: center;
-  padding-block: 0.3em;
+  padding-block: 0.4em;
-}
-.navigation > .tab:hover,
-.navigation > .tab:focus-visible {
-  background-color: var(--color-focus-gray);
 }
 .navigation > .tab.active {
-  border-bottom: solid 4px var(--color-blue);
+  border-bottom: 4px solid var(--color-blue);
   color: var(--color-blue);
   fill: var(--color-blue);
 }
 
-
+.topside-area {
-.topside {
   grid-area: topside;
 }
-.leftside {
+.leftside-area {
   grid-area: leftside;
 }
-.main {
+.main-area {
   grid-area: main;
 }
-.rightside {
+.rightside-area {
   grid-area: rightside;
 }
 
-
 .buttongrid {
   display: grid;
   gap: 0.4em;
@@ -273,14 +332,14 @@ header {
   grid-template-columns: auto 1fr auto;
   grid-template-rows: max-content;
 }
-.tools {
+.tools-area {
   grid-area: tools;
 }
 
 
 #flashes {
   display: grid;
-  gap: 0.2em;
+  row-gap: 0.4em;
   grid-template-columns: 1fr auto auto auto 1fr;
   left: 0;
   pointer-events: none;
@@ -296,281 +355,289 @@ header {
   display: grid;
   grid-column: 2/5;
   grid-template-columns: subgrid;
+  line-height: 2.2em;
   pointer-events: auto;
 }
-.flash.alert:before {
+.flash::before {
-  content: url('pictograms/alert-outline.svg');
+  filter: invert(1);
   height: 1.4em;
   margin: 0 0.5em;
   width: 1.4em;
 }
+.flash.alert::before {
+  content: url('pictograms/alert-outline.svg');
+}
 .flash.alert {
   border-color: var(--color-red);
   background-color: var(--color-red);
 }
-.flash.notice:before {
+.flash.notice::before {
   content: url('pictograms/check-circle-outline.svg');
-  height: 1.4em;
-  margin: 0 0.5em;
-  width: 1.4em;
 }
 .flash.notice {
   border-color: var(--color-blue);
   background-color: var(--color-blue);
 }
-.flash > div {
+.flash svg {
-  grid-column: 2;
-}
-/* NOTE: currently flash button inherits some unnecessary styles from generic
- * button. */
-.flash > button {
-  border: none;
-  color: inherit;
   cursor: pointer;
-  font-size: 1.4em;
+  fill: white;
-  font-weight: bold;
+  height: 2.2em;
-  grid-column: 3;
   opacity: 0.6;
-  padding: 0.2em 0.4em;
+  padding: 0.4em 0.5em;
+  width: 2.4em;
 }
-.flash > button:hover {
+.flash svg:hover {
   opacity: 1;
 }
 
 
-/* TODO: Update styling, including rem removal. */
+.labeled-form {
-form table {
+  align-items: center;
-  border-spacing: 0.8rem;
+  display: grid;
+  gap: 0.9em 1.1em;
+  grid-template-columns: 1fr minmax(max-content, 0.5fr) 1fr;
 }
-form tr td:first-child {
+.labeled-form label {
   color: var(--color-gray);
   font-size: 0.9rem;
-  padding-right: 0.25rem;
+  grid-column: 1;
   text-align: right;
+  white-space: nowrap;
 }
-form label.required {
+.labeled-form label.required {
   font-weight: bold;
 }
-form label.error,
+/* Don't style `label.error + input` if case already covered by `input:invalid`. */
-form td.error::after {
+.labeled-form label.error {
   color: var(--color-red);
 }
-form td.error {
+.labeled-form em {
-  display: -webkit-box;
-}
-form td.error::after {
-  content: attr(data-content);
-  font-size: 0.9rem;
-  margin-left: 1rem;
-  padding: 0.25rem 0;
-  position: absolute;
-}
-form em {
   color: var(--color-text-gray);
   font-size: 0.75rem;
   font-weight: normal;
 }
-form input[type=submit] {
+.labeled-form input {
-  float: none;
+  grid-column: 2;
+}
+.labeled-form input[type=submit] {
   font-size: 1rem;
-  margin: 1.5rem auto 0 auto;
+  margin: 1em auto 0 auto;
-  padding: 0.75rem;
+  padding: 0.75em;
+}
+.labeled-form .auxiliary {
+  grid-column: 3;
+  /* If more buttons are needed, `grid-row` can be replaced with
+   * `reading-flow: grid-columns` to ensure proper [tabindex] order. */
+  grid-row: 1;
+  height: 100%;
+  padding-block: 0;
+}
+
+.tabular-form table {
+  border: none;
+  border-spacing: 0;
+}
+.tabular-form table td {
+  border: none;
+  padding-inline-start: 0.4em;
+  vertical-align: middle;
+}
+.tabular-form table td:first-child {
+  padding-inline-start: 0;
+}
+.tabular-form table td:last-child {
+  padding-inline-end: 0;
+}
+.tabular-form table :is(form, input, select, textarea):only-child {
+  margin-inline-start: 0;
 }
 
 
-table.items {
+.items-table {
   border-spacing: 0;
-  border: solid 1px var(--color-border-gray);
+  border: 1px solid var(--color-border-gray);
   border-radius: 0.25em;
   font-size: 0.85rem;
   text-align: left;
 }
-table.items thead {
+.items-table thead {
   font-size: 0.8rem;
 }
-table.items thead,
+.items-table thead,
-table.items tbody tr:hover {
+.items-table tbody tr:hover {
   background-color: var(--color-focus-gray);
 }
-table.items th {
+.items-table th {
-  padding-block: 0.75em;
+  padding: 0.75em 0 0.75em 1em;
   text-align: center;
 }
-table.items th,
+.items-table th:last-child {
-table.items td {
-  padding-inline: 1em 0;
-}
-/* For <a> to fill <td> completely, we use an ::after pseudoelement. */
-table.items td.link {
-  padding: 0;
-  position: relative;
-}
-table.items td.link a {
-  color: inherit;
-  font: inherit;
-}
-table.items td.link a::after {
-  content: '';
-  inset: 0;
-  position: absolute;
-}
-table.items td:first-child {
-  padding-inline-start: calc(1em + var(--depth) * 0.8em);
-}
-table.items td:has(input, textarea) {
-  padding-inline-start: calc(0.6em - 0.9px);
-}
-table.items td:first-child:has(input, textarea) {
-  padding-inline-start: calc(0.6em + var(--depth) * 0.8em - 0.9px);
-}
-table.items th:last-child {
   padding-inline-end: 0.4em;
 }
-table.items td:last-child {
+.items-table td {
+  border-top: 1px solid var(--color-border-gray);
+  height: 2.4em;
+  padding: 0.1em 0 0.1em calc(1em + var(--depth) * 0.8em);
+}
+.items-table td:last-child {
   padding-inline-end: 0.1em;
 }
-table.items td {
+.items-table :is(form, input, select, textarea):only-child {
-  border-top: solid 1px var(--color-border-gray);
+  margin-inline-start: calc(-0.4em - 0.9px);
-  height: 2.4em;
-  padding-block: 0.1em;
 }
-table.items .actions {
+/* For <a> to fill table cell completely, we use an `::after` pseudoelement. */
-  display: flex;
+/* TODO: expand to whole row? will require adjusting z-index on inputs/buttons */
+.items-table td:has(> .link) {
+  position: relative;
+}
+.items-table .link::after {
+  content: '';
+  inset: -1px 0 0 0;
+  position: absolute;
+}
+.items-table .flex {
   gap: 0.4em;
   justify-content: end;
 }
-table.items .actions.centered {
+.items-table .dropzone {
-  justify-content: center;
-}
-table.items tr.dropzone {
   position: relative;
 }
-table.items tr.dropzone::after {
+.items-table .dropzone::after {
   content: '';
   inset: 1px 0 0 0;
   position: absolute;
-  outline: dashed 2px var(--color-blue);
+  outline: 2px dashed var(--color-blue);
   outline-offset: -1px;
   z-index: var(--z-index-table-row-outline);
 }
-table.items td.handle {
+.items-table .handle {
-  cursor: move;
+  cursor: grab;
 }
-table.items tr.form td {
+.items-table .form td {
   vertical-align: top;
 }
-
+.items-table td:not(:first-child),
-/* TODO: replace :hover:focus-visible combos with proper LOVE stye order */
-/* TODO: Update styling, including rem removal. */
-table.items td.link a:hover,
-table.items td.link a:focus-visible,
-table.items td.link a:hover:focus-visible {
-  text-decoration: underline;
-  text-decoration-thickness: 0.05rem;
-  text-underline-offset: 0.2rem;
-}
-table.items td.link a:hover {
-  color: var(--color-blue);
-}
-table.items td.link a:focus-visible {
-  text-decoration-color: var(--color-gray);
-}
-table.items td.link a:hover:focus-visible {
-  color: var(--color-dark-blue);
-}
-
-table.items td:not(:first-child),
 .grayed {
   color: var(--color-table-gray);
-  fill: var(--color-table-gray);
+  fill: var(--color-gray);
 }
-table.items td.hint {
+.items-table td:has(> svg:only-child) {
-  color: var(--color-table-gray);
-  font-style: italic;
-  font-size: 0.8rem;
-  padding: 1em;
-}
-table.items svg {
-  height: 1.2rem;
-  vertical-align: middle;
-  width: 1.2rem;
-}
-table.items td.svg {
   text-align: center;
 }
-table.items td.number {
-  text-align: right;
-}
-table.items .button,
-table.items button,
-table.items input[type=submit] {
-  font-weight: normal;
-  padding: 0.3em;
-}
-table.items input:not([type=submit]):not([type=checkbox]),
-table.items select,
-table.items textarea {
-  padding-block: 0.375em;
-}
-/* TODO: find a way (layers?) to style inputs differently while making sure
- * hover works properly without using :not(:hover) selectors here. */
-table.items .button:not(:hover),
-table.items button:not(:hover),
-table.items input:not(:hover),
-table.items select:not(:hover),
-table.items textarea:not(:hover) {
-  border-color: var(--color-border-gray);
-}
-table.items .button:not(:hover),
-table.items button:not(:hover),
-table.items input[type=submit]:not(:hover),
-table.items select:not(:hover) {
-  color: var(--color-table-gray);
-}
-table.items select:focus-within,
-table.items select:focus-visible {
-  color: black;
-}
 
-form a[name=cancel] {
-  border-color: var(--color-border-gray);
-  color: var(--color-nav-gray);
-  fill: var(--color-nav-gray);
-}
-form table.items {
-  border: none;
-}
-form table.items td {
-  border: none;
-  text-align: left;
-  vertical-align: middle;
-}
-form table.items td:first-child {
-  color: inherit;
-}
 
-.centered {
+.center {
   margin: 0 auto;
 }
-.extendedright {
+.hexpand {
-  margin-right: auto;
+  width: 100%;
 }
-.hflex {
+.flex {
   display: flex;
   gap: 0.8em;
 }
-.vflex {
+.flex.reverse {
-  display: flex;
+  flex-direction: row-reverse;
-  gap: 0.8em;
+}
+.flex.vertical {
   flex-direction: column;
 }
-[disabled] {
+.hint {
-  border-color: var(--color-border-gray) !important;
+  color: var(--color-table-gray);
-  color: var(--color-border-gray) !important;
+  font-style: italic;
-  cursor: not-allowed;
+  font-size: 0.9rem;
-  fill: var(--color-border-gray) !important;
+  text-align: center;
-  pointer-events: none;
 }
-.unwrappable {
+.hmin50 {
+  min-width: 50%;
+}
+.italic {
+  color: var(--color-gray);
+  font-style: italic;
+}
+.ralign {
+  text-align: right;
+}
+.rextend {
+  margin-right: auto;
+}
+
+
+details {
+  align-content: center;
+  position: relative;
+}
+summary {
+  align-items: center;
+  color: var(--color-gray);
+  display: flex;
+  gap: 0.4em;
+  height: 100%;
   white-space: nowrap;
 }
+summary::before {
+  background-color: currentColor;
+  content: "";
+  height: 1em;
+  mask-image: url('pictograms/chevron-down.svg');
+  mask-size: cover;
+  width: 1em;
+}
+summary:has(.button) {
+  padding-block: 0;
+  padding-inline-end: 0;
+}
+summary .button {
+  border: 1px solid var(--color-border-gray);
+  border-radius: inherit;
+  border-top-left-radius: 0;
+  border-bottom-left-radius: 0;
+  border-style: none none none solid;
+  height: 100%;
+}
+summary span {
+  width: 100%;
+}
+details[open] summary::before {
+  transform: scaleY(-1);
+}
+summary::marker {
+  padding-left: 0.25em;
+}
+/* NOTE: use `details[open]::details-content` once widely available. */
+details[open] ul {
+  background-color: white;
+  border: 1px solid var(--color-border-gray);
+  border-radius: 0.25em;
+  box-shadow: 1px 1px 3px var(--color-border-gray);
+  margin: -1px 0 0 0;
+  padding-left: 0;
+  position: absolute;
+  width: 100%;
+}
+li:hover {
+  background-color: var(--color-focus-gray);
+}
+li label {
+  align-items: center;
+  display: flex;
+  line-height: 1.4em;
+}
+li input[type=checkbox] {
+  margin: 0 0.25em;
+}
+li::marker {
+  content: '';
+}
+/*
+ * TODO:
+ * * disable <label> containing disabled checkbox: `label:has(input[disabled])`,
+ * * disabled label styling,
+ * * focused label styling (currently only checkbox has focus),
+ * * disabled checkbox blue square focus removal.
+ * */
+
+#measurement_form {
+  min-width: 66%;
+  width: max-content;
+}

app/controllers/application_controller.rb

@@ -25,6 +25,18 @@ class ApplicationController < ActionController::Base
   #   Turbo will reload 2nd time with HTML format and flashes will be lost.
   rescue_from *ActionDispatch::ExceptionWrapper.rescue_responses.keys, with: :rescue_turbo
 
+  # Required by #respond_with (gem `responders`) used by Devise controllers.
+  respond_to :html, :turbo_stream
+
+  def after_sign_in_path_for(resource)
+    # TODO: allow setting path per-user or save last path in session and restore
+    units_path
+  end
+
+  def after_sign_out_path_for(resource)
+    new_user_session_path
+  end
+
   protected
 
   def current_user_disguised?

app/controllers/measurements_controller.rb

@@ -1,36 +1,11 @@
 class MeasurementsController < ApplicationController
-  before_action :find_quantity, only: [:new, :discard]
-  before_action :find_prev_quantities, only: [:new, :discard]
-
   def index
-    @quantities = current_user.quantities.ordered
+    @measurements = []
+    #@measurements = current_user.units.ordered.includes(:base, :subunits)
   end
 
   def new
-    quantities =
+    @quantities = current_user.quantities.ordered
-      case params[:scope]
-      when 'children'
-        @quantity.subquantities
-      when 'subtree'
-        @quantity.progenies
-      else
-        [@quantity]
-      end
-    quantities -= @prev_quantities
-    @readouts = current_user.readouts.build(quantities.map { |q| {quantity: q} })
-
-    @units = current_user.units.ordered
-
-    all_quantities = @prev_quantities + quantities
-    @common_ancestor = current_user.quantities
-      .common_ancestors(all_quantities.map(&:parent_id)).first
-  end
-
-  def discard
-    @prev_quantities -= [@quantity]
-
-    @common_ancestor = current_user.quantities
-      .common_ancestors(@prev_quantities.map(&:parent_id)).first
   end
 
   def create
@@ -38,15 +13,4 @@ class MeasurementsController < ApplicationController
 
   def destroy
   end
-
-  private
-
-  def find_quantity
-    @quantity = current_user.quantities.find_by!(id: params[:id])
-  end
-
-  def find_prev_quantities
-    prev_quantity_ids = params[:readouts]&.map { |r| r[:quantity_id] } || []
-    @prev_quantities = current_user.quantities.find(prev_quantity_ids)
-  end
 end

app/controllers/readouts_controller.rb

@@ -0,0 +1,39 @@
+class ReadoutsController < ApplicationController
+  before_action :find_quantities, only: [:new]
+  before_action :find_quantity, only: [:discard]
+  before_action :find_prev_quantities, only: [:new, :discard]
+
+  def new
+    @quantities -= @prev_quantities
+    # TODO: raise ParameterInvalid if new_quantities.empty?
+    @readouts = @quantities.map { |q| q.readouts.build }
+
+    @user_units = current_user.units.ordered
+
+    quantities = @prev_quantities + @quantities
+    @superquantity = current_user.quantities
+      .common_ancestors(quantities.map(&:parent_id)).first
+  end
+
+  def discard
+    @prev_quantities -= [@quantity]
+
+    @superquantity = current_user.quantities
+      .common_ancestors(@prev_quantities.map(&:parent_id)).first
+  end
+
+  private
+
+  def find_quantities
+    @quantities = current_user.quantities.find(params[:quantity])
+  end
+
+  def find_quantity
+    @quantity = current_user.quantities.find_by!(id: params[:id])
+  end
+
+  def find_prev_quantities
+    prev_quantity_ids = params[:readouts]&.map { |r| r[:quantity_id] } || []
+    @prev_quantities = current_user.quantities.find(prev_quantity_ids)
+  end
+end

app/controllers/units_controller.rb

@@ -17,7 +17,7 @@ class UnitsController < ApplicationController
   end
 
   def create
-    @unit = current_user.units.new(unit_params)
+    @unit = current_user.units.new(params.expect(Unit::ATTRIBUTES))
     if @unit.save
       @before = @unit.successive
       flash.now[:notice] = t('.success', unit: @unit)
@@ -30,7 +30,7 @@ class UnitsController < ApplicationController
   end
 
   def update
-    if @unit.update(unit_params.except(:base_id))
+    if @unit.update(params.except(:base_id).expect(Unit::ATTRIBUTES))
       flash.now[:notice] = t('.success', unit: @unit)
     else
       render :edit
@@ -40,11 +40,11 @@ class UnitsController < ApplicationController
   # TODO: Avoid double table width change by first un-hiding table header,
   # then displaying index, e.g. by re-displaying header in index
   def rebase
-    permitted = params.require(:unit).permit(:base_id)
+    unit_params = params.expect(unit: :base_id)
-    permitted.merge!(multiplier: 1) if permitted[:base_id].blank? && @unit.multiplier != 1
+    unit_params.merge!(multiplier: 1.0) if unit_params[:base_id].blank?
 
     @previous_base = @unit.base
-    @unit.update!(permitted)
+    @unit.update!(unit_params)
 
     @before = @unit.successive
     if @unit.multiplier_previously_changed?
@@ -59,10 +59,6 @@ class UnitsController < ApplicationController
 
   private
 
-  def unit_params
-    params.require(:unit).permit(Unit::ATTRIBUTES)
-  end
-
   def find_unit
     @unit = current_user.units.find_by!(id: params[:id])
   end

app/controllers/user/profiles_controller.rb

@@ -1,5 +1,8 @@
-class RegistrationsController < Devise::RegistrationsController
+class User::ProfilesController < Devise::RegistrationsController
-  before_action :authenticate_user!, only: [:edit, :update, :destroy]
+  def destroy
+    # TODO: Disallow/disable deletion for last admin account; update :edit view
+    super
+  end
 
   protected
 

app/controllers/users_controller.rb

@@ -37,7 +37,7 @@ class UsersController < ApplicationController
   end
 
   # NOTE: limited actions availabe to :admin by design. Users are meant to
-  # manage their accounts by themselves through registrations. :admin
+  # manage their accounts by themselves through profiles. :admin
   # is allowed to sign-in (disguise) as user and make changes from there.
 
   protected

app/helpers/application_helper.rb

@@ -1,59 +1,85 @@
 module ApplicationHelper
-  # TODO: replace legacy content_tag with tag.tagname
+  class LabeledFormBuilder < ActionView::Helpers::FormBuilder
-  class LabelledFormBuilder < ActionView::Helpers::FormBuilder
+    (field_helpers - [:label, :hidden_field]).each do |selector|
-    (field_helpers - [:label]).each do |selector|
       class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
         def #{selector}(method, options = {})
-          labelled_row_for(method, options) { super }
+          labeled_field_for(method, options) { super }
         end
       RUBY_EVAL
     end
 
     def select(method, choices = nil, options = {}, html_options = {})
-      labelled_row_for(method, options) { super }
+      labeled_field_for(method, options) { super }
     end
 
-    def submit(value, options = {})
+    def submit(value = nil, options = {})
-      @template.content_tag :tr do
+      value, options = nil, value if value.is_a?(Hash)
-        @template.content_tag :td, super, colspan: 2
+      options[:class] = @template.class_names('button', options[:class])
-      end
+      super
-    end
-
-    def form_for(&block)
-      @template.content_tag(:table, class: "centered") { yield(self) } +
-      # Display leftover error messages (there shouldn't be any)
-      @template.content_tag(:div, @object&.errors.full_messages.join(@template.tag(:br)))
     end
 
     private
 
-    def labelled_row_for(method, options)
+    def labeled_field_for(method, options)
-      @template.content_tag :tr do
+      field = if options.delete(:readonly) then
-        @template.content_tag(:td, label_for(method, options), class: "unwrappable") +
+                value = object.public_send(method)
-        @template.content_tag(:td, options.delete(:readonly) ? @object.public_send(method) : yield,
+                value = @template.l(value) if value.respond_to?(:strftime)
-          @object&.errors[method].present? ?
+                value ||= options[:placeholder]
-            {class: "error", data: {content: @object&.errors.delete(method).join(" and ")}} :
+              else
-            {})
+                yield
-      end
+              end
+      label_for(method, options) + field
     end
 
     def label_for(method, options = {})
-      return '' if options[:label] == false
-
-      text = options.delete(:label)
-      text ||= @object.class.human_attribute_name(method).capitalize
       classes = @template.class_names(required: options[:required],
-                                      error: @object&.errors[method].present?)
+                                      error: object.errors[method].present?)
-      label = label(method, "#{text}:", class: classes)
-      hint = options.delete(:hint)
 
-      label + (@template.tag(:br) + @template.content_tag(:em, hint) if hint)
+      handler = {missing_interpolation_argument_handler: method(:interpolation_missing)}
+      # Label translation search order:
+      #   controller.action.* => helpers.label.model.* => activerecord.attributes.model.*
+      # First 2 levels are translated recursively.
+      label(method, class: classes) do |builder|
+        translation = I18n.config.with(**handler) { deep_translate(method, **options) }
+        translation.presence || "#{builder.translation}:"
+      end
+    end
+
+    def interpolation_missing(key, values, string)
+      @template.instance_values[key.to_s] || deep_translate(key, **values)
+    end
+
+    # Extension to label text translation:
+    # * recursive translation,
+    # * interpolation of (_relative_) translation key names and instance variables,
+    # * pluralization based on any interpolable value
+    # TODO: add unit tests for the above
+    def deep_translate(key, **options)
+      options[:default] = [
+        :".#{key}",
+        :"helpers.label.#{@object_name}.#{key}_html",
+        :"helpers.label.#{@object_name}.#{key}",
+        ""
+      ]
+
+      # At least 1 interpolation key is required for #translate to act on
+      # missing interpolation arguments (i.e. call custom handler).
+      # Also setting `key` to nil avoids recurrent translation.
+      options[key] = nil
+
+      @template.t(".#{key}_html", **options) do |translation, resolved_key|
+        if translation.is_a?(Array) && (count = translation.to_h[:count])
+          @template.t(resolved_key, count: I18n.interpolate(count, **options), **options)
+        else
+          translation
+        end
+      end
     end
   end
 
-  def labelled_form_for(record, options = {}, &block)
+  def labeled_form_for(record, options = {}, &block)
-    options = options.deep_merge(builder: LabelledFormBuilder, data: {turbo: false})
+    extra_options = {builder: LabeledFormBuilder, html: {class: 'labeled-form'}}
-    form_for(record, **options) { |f| f.form_for(&block) }
+    form_for(record, **merge_attributes(options, extra_options), &block)
   end
 
   class TabularFormBuilder < ActionView::Helpers::FormBuilder
@@ -75,22 +101,33 @@ module ApplicationHelper
     end
 
     def number_field(method, options = {})
-      value = object.public_send(method)
+      attr_type = object.type_for_attribute(method)
-      if value.is_a?(BigDecimal)
+      case attr_type.type
-        options[:value] = value.to_scientific
+      when :float, :double
-        type = object.class.type_for_attribute(method)
+        options[:value] = object.public_send(method)&.to_scientific
-        options[:step] ||= BigDecimal(10).power(-type.scale)
+        options[:step] ||= :any
-        options[:max] ||= BigDecimal(10).power(type.precision - type.scale) -
+        options[:min] ||= Float::MIN_15
-          options[:step]
+        options[:max] ||= Float::MAX_15
-        options[:min] = options[:min] == :step ? options[:step] : options[:min]
+        # Longest possible number (written not using exponent):
-        options[:min] ||= -options[:max]
+        #   sign (1), leading 0 (1), dot (1), exponent 0s (307), digits (15).
+        # This is only upper bound, which cannot guarantee the number won't fall
+        # out of range.
+        # TODO: add `[pattern]` to limit precision and (possibly) replace `[maxlength]`?
+        # NOTE: `[pattern]` is unavailable on `input[type=number]` and `[min]/[max]` is
+        # unavailable on `input[type=text]`.
+        options[:maxlength] ||= 3 + Float::MIN_10_EXP + Float::DIG
+        options[:size] ||= 6
       end
       super
     end
 
     def button(value = nil, options = {}, &block)
-      # button does not use #objectify_options
+      # #button does not use #objectify_options/@default_options
-      options.merge!(@options.slice(:form))
+      value, options = nil, value if value.is_a?(Hash)
+      options = options.merge(
+        @default_options.slice(:form),
+        class: @template.class_names('button', options[:class])
+      )
       super
     end
 
@@ -111,19 +148,22 @@ module ApplicationHelper
     # [autofocus].  Otherwise IDs are not unique when multiple forms are open
     # and the first input gets focus.
     record_object, options = nil, record_object if record_object.is_a?(Hash)
-    options.merge!(builder: TabularFormBuilder, skip_default_ids: true)
+    extra_options = {builder: TabularFormBuilder, skip_default_ids: true}
+    options = merge_attributes(options, extra_options)
+    # TODO: set error message with setCustomValidity instead of rendering to flash?
     render_errors(record_object || record_name)
     fields_for(record_name, record_object, **options, &block)
   end
 
   def tabular_form_with(**options, &block)
-    options = options.deep_merge(builder: TabularFormBuilder,
+    extra_options = {builder: TabularFormBuilder, class: 'tabular-form',
-                                 html: {autocomplete: 'off'})
+                     html: {autocomplete: 'off'}}
-    form_with(**options, &block)
+    form_with(**merge_attributes(options, extra_options), &block)
   end
 
   def svg_tag(source, label = nil, options = {})
-    svg_tag = content_tag :svg, options do
+    label, options = nil, label if label.is_a? Hash
+    svg_tag = tag.svg(**options) do
       tag.use(href: "#{image_path(source + ".svg")}#icon")
     end
     label.blank? ? svg_tag : svg_tag + tag.span(label)
@@ -134,6 +174,7 @@ module ApplicationHelper
       ['measurements', 'scale-bathroom', :restricted],
       ['quantities', 'axis-arrow', :restricted, 'right'],
       ['units', 'weight-gram', :restricted],
+      # TODO: display users tab only if >1 user present; sole_user?/sole_admin?
       ['users', 'account-multiple-outline', :admin],
     ]
 
@@ -171,21 +212,26 @@ module ApplicationHelper
 
   def image_link_to_unless_current(name, image = nil, options = nil, html_options = {})
     name, html_options = link_or_button_options(:link, name, image, html_options)
-    html_options = html_options.deep_merge DISABLED_ATTRIBUTES if current_page?(options)
+    if current_page?(options, method: [:get, :post])
+      html_options = html_options.deep_merge DISABLED_ATTRIBUTES
+    end
     link_to name, options, html_options
   end
 
   def render_errors(records)
-    flash[:alert] ||= []
+    # Conversion of flash to Array only required because of Devise
+    # TODO: override Devise message setting to Array()?
+    flash[:alert] = Array(flash[:alert])
     Array(records).each { |record| flash[:alert] += record.errors.full_messages }
   end
 
   def render_flash_messages
     flash.map do |entry, messages|
+      # Conversion of flash to Array only required because of Devise
       Array(messages).map do |message|
         tag.div class: "flash #{entry}" do
-          tag.div(sanitize(message)) + tag.button(sanitize("&times;"), tabindex: -1,
+          tag.span(sanitize(message)) +
-                                                  onclick: "this.parentElement.remove();")
+            svg_tag('pictograms/close-outline', {onclick: "this.parentElement.remove()"})
         end
       end
     end.join.html_safe
@@ -204,8 +250,6 @@ module ApplicationHelper
   private
 
   def link_or_button_options(type, name, image = nil, html_options)
-    name = svg_tag("pictograms/#{image}", name) if image
-
     html_options[:class] = class_names(
       html_options[:class],
       'button',
@@ -216,10 +260,18 @@ module ApplicationHelper
       html_options[:onclick] = "return confirm('\#{html_options[:onclick][:confirm]}');"
     end
 
-    if type == :link && !(html_options[:onclick] || html_options.dig(:data, :turbo_stream))
+    link_is_local = html_options[:onclick] || html_options.dig(:data, :turbo_stream)
-      name += '...'
+    name = name.to_s
-    end
+    name += '...' if type == :link && !link_is_local
+    name = svg_tag("pictograms/#{image}", name) if image
 
     [name, html_options]
   end
+
+  # Like Hash#deep_merge, but aware of HTML attributes.
+  def merge_attributes(left, right)
+    left.deep_merge(right) do |key, lvalue, rvalue|
+      key == :class ? class_names(lvalue, rvalue) : rvalue
+    end
+  end
 end

app/helpers/quantities_helper.rb

@@ -1,2 +1,11 @@
 module QuantitiesHelper
+  def quantities_check_boxes(quantities)
+    # Closing <details> on focusout event depends on relatedTarget for internal
+    # actions being non-null. To ensure this, all top-layer elements of
+    # ::details-content must accept focus, e.g. <label> needs tabindex="-1" */
+    collection_check_boxes(nil, :quantity, quantities, :id, :to_s_with_depth,
+                           include_hidden: false) do |b|
+      content_tag :li, b.label(tabindex: -1) { b.check_box + b.text }
+    end
+  end
 end

app/javascript/application.js

@@ -9,31 +9,82 @@ function showPage(event) {
 }
 document.addEventListener('turbo:load', showPage)
 
+function detailsChange(event) {
+  var target = event.currentTarget
+  var count = target.querySelectorAll('input:checked:not([disabled])').length
+  var span = target.querySelector('summary > span')
+  var button = target.querySelector('button')
+  if (count > 0) {
+    span.textContent = count + ' selected';
+    Turbo.StreamElement.prototype.enableElement(button)
+  } else {
+    span.textContent = span.getAttribute('data-prompt')
+    Turbo.StreamElement.prototype.disableElement(button)
+  }
+}
+window.detailsChange = detailsChange
+
+/* Close open <details> when focus lost */
+function detailsClose(event) {
+  if (!event.relatedTarget ||
+      event.relatedTarget.closest("details") != event.currentTarget) {
+    event.currentTarget.removeAttribute("open")
+  }
+}
+window.detailsClose = detailsClose
+
+window.detailsObserver = new MutationObserver((mutations) => {
+  mutations[0].target.dispatchEvent(new Event('change', {bubbles: true}))
+});
+
+function formValidate(event) {
+  var id = event.submitter.getAttribute("data-validate")
+  if (!id) return;
+
+  var input = document.getElementById(id)
+  if (!input.checkValidity()) {
+    input.reportValidity()
+    event.preventDefault()
+  }
+}
+window.formValidate = formValidate
+
 
 /* Turbo stream actions */
+Turbo.StreamElement.prototype.disableElement = function(element) {
+    element.setAttribute("disabled", "disabled")
+    element.setAttribute("aria-disabled", "true")
+    element.setAttribute("tabindex", "-1")
+}
+Turbo.StreamActions.disable = function() {
+  this.targetElements.forEach((e) => { this.disableElement(e) })
+}
+
 Turbo.StreamElement.prototype.enableElement = function(element) {
     element.removeAttribute("disabled")
     element.removeAttribute("aria-disabled")
-    // 'tabindex' is not used explicitly, so removing it is safe
+    // Assume 'tabindex' is not used explicitly, so removing it is safe
     element.removeAttribute("tabindex")
 }
-
-Turbo.StreamActions.disable = function() {
-  this.targetElements.forEach((e) => {
-    e.setAttribute("disabled", "disabled")
-    e.setAttribute("aria-disabled", "true")
-    e.setAttribute("tabindex", "-1")
-  })
-}
-
 Turbo.StreamActions.enable = function() {
   this.targetElements.forEach((e) => { this.enableElement(e) })
 }
 
+/* TODO: change to visibility = collapse to avoid width change? */
 Turbo.StreamActions.hide = function() {
   this.targetElements.forEach((e) => { e.style.display = "none" })
 }
 
+Turbo.StreamActions.show = function() {
+  this.targetElements.forEach((e) => { e.style.removeProperty("display") })
+}
+
+/*
+Turbo.StreamActions.collapse = function() {
+  this.targetElements.forEach((e) => { e.style.visibility = "collapse" })
+}
+*/
+
 Turbo.StreamActions.close_form = function() {
   this.targetElements.forEach((e) => {
     /* Move focus if there's no focus or focus inside form being closed */
@@ -54,28 +105,63 @@ Turbo.StreamActions.close_form = function() {
   })
 }
 
+Turbo.StreamActions.unselect = function() {
+  this.targetElements.forEach((e) => {
+    e.checked = false
+    this.enableElement(e)
+  })
+}
 
-/* Items table drag and drop support */
+function formProcessKey(event) {
-function processKey(event) {
+  switch (event.key) {
-  if (event.key == "Escape") {
+    case "Escape":
-    event.currentTarget.querySelector("a[name=cancel]").click();
+      event.currentTarget.querySelector("a[name=cancel]").click()
+      break
+    case "Enter":
+      event.currentTarget.querySelector("button[name=button]").click()
+      event.preventDefault()
+      break
   }
 }
-window.processKey = processKey;
+window.formProcessKey = formProcessKey
 
-var lastEnterTime;
+function detailsProcessKey(event) {
-function dragStart(event) {
+  // TODO: up/down arrows to move focus to prev/next line
-  lastEnterTime = event.timeStamp;
+  switch (event.key) {
-  var row = event.currentTarget;
+    case "Escape":
-  row.closest("table").querySelectorAll("thead tr").forEach((tr) => {
+      if (event.currentTarget.hasAttribute("open")) {
-    tr.toggleAttribute("hidden");
+        event.currentTarget.removeAttribute("open")
-  });
+        event.stopPropagation()
-  event.dataTransfer.setData("text/plain", row.getAttribute("data-drag-path"));
+      }
-  var rowRectangle = row.getBoundingClientRect();
+      break
-  event.dataTransfer.setDragImage(row, event.x - rowRectangle.left, event.y - rowRectangle.top);
+    case "Enter":
-  event.dataTransfer.dropEffect = "move";
+      var button = event.currentTarget.querySelector("button:not([disabled])")
+      if (button) {
+        button.click()
+        // Autofocus won't be respected unless target is blurred
+        event.target.blur()
+        event.preventDefault()
+        event.stopPropagation()
+      }
+      break
+  }
 }
-window.dragStart = dragStart;
+window.detailsProcessKey = detailsProcessKey;
+
+/* Items table drag and drop support */
+var lastEnterTime
+function dragStart(event) {
+  lastEnterTime = event.timeStamp
+  var row = event.currentTarget
+  row.closest("table").querySelectorAll("thead tr").forEach((tr) => {
+    tr.toggleAttribute("hidden")
+  })
+  event.dataTransfer.setData("text/plain", row.getAttribute("data-drag-path"))
+  var rowRectangle = row.getBoundingClientRect()
+  event.dataTransfer.setDragImage(row, event.x - rowRectangle.left, event.y - rowRectangle.top)
+  event.dataTransfer.dropEffect = "move"
+}
+window.dragStart = dragStart
 
 /*
 * Drag tracking assumptions (based on FF 122.0 experience):
@@ -87,44 +173,44 @@ window.dragStart = dragStart;
 * and outside. This should probably be fixed in browser, than patched here.
 */
 function dragEnter(event) {
-  //console.log(event.timeStamp + " " + event.type + ": " + event.currentTarget.id);
+  //console.log(event.timeStamp + " " + event.type + ": " + event.currentTarget.id)
-  dragLeave(event);
+  dragLeave(event)
-  lastEnterTime = event.timeStamp;
+  lastEnterTime = event.timeStamp
-  const id = event.currentTarget.getAttribute("data-drop-id");
+  const id = event.currentTarget.getAttribute("data-drop-id")
-  document.getElementById(id).classList.add("dropzone");
+  document.getElementById(id).classList.add("dropzone")
 }
-window.dragEnter = dragEnter;
+window.dragEnter = dragEnter
 
 function dragOver(event) {
-  event.preventDefault();
+  event.preventDefault()
 }
-window.dragOver = dragOver;
+window.dragOver = dragOver
 
 function dragLeave(event) {
-  //console.log(event.timeStamp + " " + event.type + ": " + event.currentTarget.id);
+  //console.log(event.timeStamp + " " + event.type + ": " + event.currentTarget.id)
   // Leave has been accounted for by Enter at the same timestamp, processed earlier
-  if (event.timeStamp <= lastEnterTime) return;
+  if (event.timeStamp <= lastEnterTime) return
   event.currentTarget.closest("table").querySelectorAll(".dropzone").forEach((tr) => {
-    tr.classList.remove("dropzone");
+    tr.classList.remove("dropzone")
-  });
+  })
 }
-window.dragLeave = dragLeave;
+window.dragLeave = dragLeave
 
 function dragEnd(event) {
-  dragLeave(event);
+  dragLeave(event)
   event.currentTarget.closest("table").querySelectorAll("thead tr").forEach((tr) => {
-    tr.toggleAttribute("hidden");
+    tr.toggleAttribute("hidden")
-  });
+  })
 }
-window.dragEnd = dragEnd;
+window.dragEnd = dragEnd
 
 function drop(event) {
-  event.preventDefault();
+  event.preventDefault()
 
-  var params = new URLSearchParams();
+  var params = new URLSearchParams()
-  var id_param = event.currentTarget.getAttribute("data-drop-id-param");
+  var id_param = event.currentTarget.getAttribute("data-drop-id-param")
-  var id = event.currentTarget.getAttribute("data-drop-id").split("_").pop();
+  var id = event.currentTarget.getAttribute("data-drop-id").split("_").pop()
-  params.append(id_param, id);
+  params.append(id_param, id)
 
   fetch(event.dataTransfer.getData("text/plain"), {
     body: params,
@@ -138,4 +224,4 @@ function drop(event) {
   .then(response => response.text())
   .then(html => Turbo.renderStreamMessage(html))
 }
-window.drop = drop;
+window.drop = drop

app/models/measurement.rb

@@ -0,0 +1,3 @@
+class Measurement
+  include ActiveModel::Model
+end

app/models/note.rb

@@ -0,0 +1,3 @@
+class Note < ApplicationRecord
+  ATTRIBUTES = [:text]
+end

app/models/quantity.rb

@@ -6,6 +6,7 @@ class Quantity < ApplicationRecord
   belongs_to :parent, optional: true, class_name: "Quantity"
   has_many :subquantities, ->{ order(:name) }, class_name: "Quantity",
     inverse_of: :parent, dependent: :restrict_with_error
+  has_many :readouts, dependent: :restrict_with_error
 
   validate if: ->{ parent.present? } do
     errors.add(:parent, :user_mismatch) unless user_id == parent.user_id
@@ -100,6 +101,11 @@ class Quantity < ApplicationRecord
     name
   end
 
+  def to_s_with_depth
+    # em space, U+2003
+    ' ' * depth + name
+  end
+
   def destroyable?
     subquantities.empty?
   end

app/models/readout.rb

@@ -4,4 +4,6 @@ class Readout < ApplicationRecord
   belongs_to :user
   belongs_to :quantity
   belongs_to :unit
+
+  # TODO: validate quantity.user_id == unit.user_id != NULL
 end

app/models/unit.rb

@@ -1,9 +1,10 @@
 class Unit < ApplicationRecord
-  ATTRIBUTES = [:symbol, :description, :multiplier, :base_id]
+  ATTRIBUTES = {unit: [:symbol, :description, :multiplier, :base_id]}
 
   belongs_to :user, optional: true
   belongs_to :base, optional: true, class_name: "Unit"
-  has_many :subunits, class_name: "Unit", inverse_of: :base, dependent: :restrict_with_error
+  has_many :subunits, class_name: "Unit", inverse_of: :base,
+    dependent: :restrict_with_error
 
   validate if: ->{ base.present? } do
     errors.add(:base, :user_mismatch) unless user_id == base.user_id
@@ -13,8 +14,8 @@ class Unit < ApplicationRecord
   validates :symbol, presence: true, uniqueness: {scope: :user_id},
     length: {maximum: type_for_attribute(:symbol).limit}
   validates :description, length: {maximum: type_for_attribute(:description).limit}
-  validates :multiplier, numericality: {equal_to: 1}, unless: :base
+  validates :multiplier, numericality: {equal_to: 1.0}, unless: :base
-  validates :multiplier, numericality: {greater_than: 0, precision: true, scale: true}, if: :base
+  validates :multiplier, numericality: {greater_than: 0.0}, if: :base
 
   scope :defaults, ->{ where(user: nil) }
   scope :defaults_diff, ->{
@@ -76,16 +77,14 @@ class Unit < ApplicationRecord
       .from(units).group(:base_id, :symbol)
   }
   scope :ordered, ->{
-    left_outer_joins(:base).order(ordering)
+    left_outer_joins(:base).order([
+      arel_table.coalesce(Arel::Table.new(:bases_units)[:symbol], arel_table[:symbol]),
+      arel_table[:base_id].not_eq(nil),
+      arel_table[:multiplier],
+      arel_table[:symbol]
+    ])
   }
 
-  def self.ordering
-    [arel_table.coalesce(Arel::Table.new(:bases_units)[:symbol], arel_table[:symbol]),
-     arel_table[:base_id].not_eq(nil),
-     :multiplier,
-     :symbol]
-  end
-
   before_destroy do
     # TODO: disallow destruction if any object depends on this unit
     nil
@@ -103,21 +102,21 @@ class Unit < ApplicationRecord
     user_id.nil?
   end
 
-  # Should only by invoked on Units returned from #defaults_diff which are #portable
+  # Should only by invoked on Units returned from #defaults_diff which are #portable.
   def port!(recipient)
     recipient_base = base && Unit.find_by!(symbol: base.symbol, user: recipient)
-    params = slice(ATTRIBUTES - [:symbol, :base_id])
+    params = slice(ATTRIBUTES[:unit] - [:symbol, :base_id])
     Unit.find_or_initialize_by(user: recipient, symbol: symbol)
       .update!(base: recipient_base, **params)
   end
 
   def successive
     units = Unit.arel_table
-    lead = Arel::Nodes::NamedFunction.new('LAG', [units[:id]])
+    Unit.with(units_with_lag: user.units.left_outer_joins(:base).select(
-    window = Arel::Nodes::Window.new.order(*Unit.ordering)
+      units[Arel.star],
-    lag_id = lead.over(window).as('lag_id')
+      Arel::Nodes::NamedFunction.new('LAG', [units[:id]])
-    Unit.with(
+        .over(Arel::Nodes::Window.new.order(Unit.ordered.order_values)).as('lag_id')
-      units: user.units.left_outer_joins(:base).select(units[Arel.star], lag_id)
+    )).from(Arel::Table.new(:units_with_lag).as(:units))
-    ).where(units[:lag_id].eq(id)).first
+      .where(units[:lag_id].eq(id)).take
   end
 end

app/models/user.rb

@@ -12,10 +12,10 @@ class User < ApplicationRecord
     disabled: 0,    # administratively disallowed to sign in
   }, default: :active, validate: true
 
-  has_many :readouts, dependent: :destroy
+  has_many :readouts, dependent: :delete_all
   accepts_nested_attributes_for :readouts
-  has_many :quantities, dependent: :destroy
+  has_many :quantities, dependent: :delete_all
-  has_many :units, dependent: :destroy
+  has_many :units, dependent: :delete_all
 
   validates :email, presence: true, uniqueness: true,
     length: {maximum: type_for_attribute(:email).limit}

app/views/default/units/_unit.html.erb

@@ -5,7 +5,7 @@
   </td>
 
   <% if current_user.at_least(:active) %>
-    <td class="actions">
+    <td class="flex">
       <% unless unit.portable.nil? %>
         <% if unit.default? %>
           <%= image_button_to_if unit.portable?, t('.import'), 'download-outline',

app/views/default/units/index.html.erb

@@ -1,16 +1,17 @@
-<div class="rightside buttongrid">
+<div class="rightside-area buttongrid">
   <% if current_user.at_least(:active) %>
     <%# TODO: implement Import all %>
     <%#= image_button_to t('.import_all'), 'download-multiple-outline',
       import_all_default_units_path, data: {turbo_stream: true} %>
   <% end %>
-  <%= image_link_to t('.back'), 'arrow-left-bold-outline', units_path, class: 'tools' %>
+  <%= image_link_to t('.back'), 'arrow-left-bold-outline', units_path,
+    class: 'tools-area' %>
 </div>
 
-<table class="main items">
+<table class="main-area items-table">
   <thead>
     <tr>
-      <th><%= User.human_attribute_name(:symbol).capitalize %></th>
+      <th><%= Unit.human_attribute_name(:symbol) %></th>
       <% if current_user.at_least(:active) %>
         <th><%= t '.actions' %></th>
       <% end %>

app/views/layouts/application.html.erb

@@ -23,10 +23,10 @@
   </head>
 
   <body>
-    <header class="hflex">
+    <header class="flex">
       <%= image_link_to t(".source_code"), "code-braces", source_code_url %>
       <%= image_link_to t(".issue_tracker"), "bug-outline", issue_tracker_url,
-            class: "extendedright" %>
+        class: "rextend" %>
       <% if user_signed_in? %>
         <%= image_link_to_unless_current(current_user, "account-wrench-outline",
           edit_user_registration_path) %>
@@ -47,7 +47,7 @@
       <%= render_flash_messages %>
     </div>
 
-    <%# Allow overwriting/clearing navigation menu for some views %>
+    <%# Allows overwriting/clearing navigation menu for some views %>
     <nav class="navigation">
       <%= content_for(:navigation) || (navigation_menu if user_signed_in?) %>
     </nav>

app/views/measurements/_form.html.erb

@@ -1,25 +1,45 @@
-<% @readouts.each do |readout| %>
+<%= tabular_form_with model: Measurement.new, id: :measurement_form,
-  <%= tabular_fields_for 'readouts[]', readout do |form| %>
+  class: 'topside-area flex vertical center',
-    <%- tag.tr id: dom_id(readout.quantity, :new, :readout),
+  html: {onkeydown: 'formProcessKey(event)'} do |form| %>
-               onkeydown: 'processKey(event)' do %>
-      <%= tag.td id: dom_id(readout.quantity, nil, :pathname) do %>
-        <%= readout.quantity.relative_pathname(@common_ancestor) %>
-      <%end%>
-      <td>
-        <%= form.number_field :value, required: true, autofocus: true, size: 10 %>
-      </td>
-      <td>
-        <%= form.select :unit_id, options_from_collection_for_select(
-          @units, :id, ->(u){ sanitize('&emsp;'*(u.base_id ? 1 : 0) + u.symbol) }
-        ) %>
-      </td>
 
-      <td class="actions">
+  <table class="items-table center">
-        <%= image_button_tag '', 'delete-outline', class: 'dangerous',
+    <tbody id="readouts">
-          formaction: discard_new_measurement_path(readout.quantity),
+      <%= tabular_fields_for @measurement do |form| %>
-          formmethod: :get, formnovalidate: true, data: {turbo_stream: true} %>
+        <tr class="italic">
-        <%= form.hidden_field :quantity_id %>
+          <td class="hexpand hmin50"><%= t '.taken_at_html' %></td>
-      </td>
+          <td colspan="3" class="ralign">
-    <% end %>
+            <%= form.datetime_field :taken_at, required: true %>
-  <% end %>
+          </td>
+        </tr>
+      <% end %>
+    </tbody>
+  </table>
+
+  <%# TODO: right-click selection; unnecessary with hierarchical tags? %>
+  <details id="quantity_select" class="center hexpand" open
+           onkeydown="detailsProcessKey(event)">
+    <summary autofocus>
+      <!-- TODO: Set content with CSS when span empty to avoid duplication -->
+      <span data-prompt="<%= t('.select_quantity') %>">
+        <%= t('.select_quantity') %>
+      </span>
+      <%= image_button_tag t(:apply), "update", name: nil, disabled: true,
+        formaction: new_readout_path, formmethod: :get, formnovalidate: true,
+        data: {turbo_stream: true} %>
+    </summary>
+    <ul><%= quantities_check_boxes(@quantities) %></ul>
+  </details>
+
+  <div class="flex reverse">
+    <%= form.button id: :create_measurement_button, disabled: true -%>
+    <%= image_link_to t(:cancel), "close-outline", measurements_path, name: :cancel,
+      class: 'auxiliary dangerous', onclick: render_turbo_stream('form_close') %>
+  </div>
 <% end %>
+
+<script>
+  quantity_select.addEventListener('focusout', detailsClose)
+  quantity_select.addEventListener('change', detailsChange)
+  detailsObserver.observe(quantity_select.querySelector('ul'),
+    {subtree: true, attributeFilter: ['disabled']})
+</script>

app/views/measurements/_form_close.html.erb

@@ -1,2 +1,4 @@
-<%= turbo_stream.update :new_readouts_form %>
 <%= turbo_stream.update :flashes %>
+<%= turbo_stream.remove :measurement_form %>
+<%= turbo_stream.show :no_items -%>
+<%= turbo_stream.enable :new_measurement_link -%>

app/views/measurements/_form_frame.html.erb

@@ -1,16 +0,0 @@
-<%= tabular_fields_for Readout.new do |form| %>
-  <fieldset>
-    <legend>
-      <%= tag.span id: :new_readouts_form_legend %>
-      <%= image_link_to '', "close-outline", measurements_path, name: :cancel,
-        class: 'dangerous', onclick: render_turbo_stream('form_close') %>
-    </legend>
-    <table class="items centered">
-      <tbody id="readouts">
-        <tr id="new_readouts_actions">
-          <td colspan="4"><div class="actions centered"><%= form.button %></div></td>
-        </tr>
-      </tbody>
-    </table>
-  </fieldset>
-<% end %>

app/views/measurements/_form_repath.html.erb

@@ -1,7 +0,0 @@
-<%= turbo_stream.update(:new_readouts_form_legend) { @common_ancestor&.pathname } %>
-
-<% @prev_quantities.each do |pq| %>
-  <%= turbo_stream.update dom_id(pq, nil, :pathname) do %>
-    <%= pq.relative_pathname(@common_ancestor) %>
-  <% end %>
-<% end %>

app/views/measurements/discard.turbo_stream.erb

@@ -1,2 +0,0 @@
-<%= turbo_stream.remove dom_id(@quantity, :new, :readout) %>
-<%= render partial: 'form_repath' %>

app/views/measurements/index.html.erb

@@ -1,20 +1,14 @@
-<div class="topside vflex">
+<%# TODO: show hint when no quantities/units defined %>
+<div class="rightside-area buttongrid">
   <% if current_user.at_least(:active) %>
-    <%# TODO: show hint when no quantities/units defined %>
+    <%= image_link_to t('.new_measurement'), 'plus-outline', new_measurement_path,
-    <%= tabular_form_with url: new_measurement_path,
+      id: :new_measurement_link, onclick: 'this.blur();',
-      html: {id: :new_readouts_form} do |f| %>
+      data: {turbo_stream: true} %>
-    <% end %>
-    <div class="hflex">
-      <%= select_tag :id, options_from_collection_for_select(
-        @quantities, :id, ->(q){ sanitize('&emsp;' * q.depth + q.name) }
-      ), form: :new_readouts_form %>
-      <% common_options = {form: :new_readouts_form, formmethod: :get,
-                           formnovalidate: true, data: {turbo_stream: true}} %>
-      <%= image_button_tag t('.new_quantity'), 'plus-outline', **common_options -%>
-      <%= image_button_tag t('.new_children'), 'plus-multiple-outline',
-        formaction: new_measurement_path(:children), **common_options -%>
-      <%= image_button_tag t('.new_subtree'), 'plus-multiple-outline',
-        formaction: new_measurement_path(:subtree), **common_options -%>
-    </div>
   <% end %>
 </div>
+
+<table class="main-area">
+  <tbody id="measurements">
+    <%= render(@measurements) || render_no_items %>
+  </tbody>
+</table>

app/views/measurements/new.turbo_stream.erb

@@ -1,9 +1,5 @@
-<%= turbo_stream.update :new_readouts_form do %>
+<%= turbo_stream.disable :new_measurement_link -%>
-  <%= render partial: 'form_frame' %>
+<%= turbo_stream.hide :no_items -%>
-<% end if @prev_quantities.empty? %>
+<%= turbo_stream.append_all 'body' do %>
-
-<%= render partial: 'form_repath' %>
-
-<%= turbo_stream.before :new_readouts_actions do %>
   <%= render partial: 'form' %>
 <% end %>

app/views/quantities/_form.html.erb

@@ -1,5 +1,5 @@
 <%= tabular_fields_for @quantity, form: form_tag do |form| %>
-  <%- tag.tr id: row, class: "form", onkeydown: "processKey(event)",
+  <%- tag.tr id: row, class: "form", onkeydown: "formProcessKey(event)",
     data: {link: link, form: form_tag, hidden_row: hidden_row} do %>
 
     <td style="--depth:<%= @quantity.depth %>">
@@ -9,7 +9,7 @@
       <%= form.text_area :description, cols: 30, rows: 1, escape: false %>
     </td>
 
-    <td class="actions">
+    <td class="flex">
       <%= form.button %>
       <%= image_link_to t(:cancel), "close-outline", quantities_path, class: 'dangerous',
         name: :cancel, onclick: render_turbo_stream('form_close', {row: row}) %>

app/views/quantities/_quantity.html.erb

@@ -5,14 +5,14 @@
            data: {drag_path: reparent_quantity_path(quantity), drop_id: dom_id(quantity),
                   drop_id_param: "quantity[parent_id]"} do %>
 
-  <td class="link" style="--depth:<%= quantity.depth %>">
+  <td style="--depth:<%= quantity.depth %>">
-    <%= link_to quantity, edit_quantity_path(quantity), onclick: 'this.blur();',
+    <%= link_to quantity, edit_quantity_path(quantity), class: 'link',
-      data: {turbo_stream: true} %>
+      onclick: 'this.blur();', data: {turbo_stream: true} %>
   </td>
   <td><%= quantity.description %></td>
 
   <% if current_user.at_least(:active) %>
-    <td class="actions">
+    <td class="flex">
       <%= image_link_to t('.new_subquantity'), 'plus-outline', new_quantity_path(quantity),
         id: dom_id(quantity, :new, :link), onclick: 'this.blur();', data: {turbo_stream: true} %>
 

app/views/quantities/index.html.erb

@@ -1,19 +1,21 @@
-<div class="rightside buttongrid">
+<div class="rightside-area buttongrid">
   <% if current_user.at_least(:active) %>
     <%= image_link_to t('.new_quantity'), 'plus-outline', new_quantity_path,
-      id: dom_id(Quantity, :new, :link), onclick: 'this.blur();', data: {turbo_stream: true} %>
+      id: dom_id(Quantity, :new, :link), onclick: 'this.blur();',
+      data: {turbo_stream: true} %>
   <% end %>
   <%#= image_link_to t('.import_quantities'), 'download-outline', default_quantities_path,
-    class: 'tools' %>
+    class: 'tools-area' %>
 </div>
 
-<%= tag.div class: 'main', id: :quantity_form %>
+<%# TODO: remove? form can be inserted directly, e.g. at the end of index %>
+<%= tag.div class: 'main-area', id: :quantity_form %>
 
-<table class="main items">
+<table class="main-area items-table">
   <thead>
     <tr>
-      <th><%= Quantity.human_attribute_name(:name).capitalize %></th>
+      <th><%= Quantity.human_attribute_name(:name) %></th>
-      <th><%= Quantity.human_attribute_name(:description).capitalize %></th>
+      <th class="hexpand"><%= Quantity.human_attribute_name(:description) %></th>
       <% if current_user.at_least(:active) %>
         <th><%= t :actions %></th>
         <th></th>

app/views/readouts/_form.html.erb

@@ -0,0 +1,24 @@
+<%# TODO: add readout reordering by dragging %>
+<%= tabular_fields_for 'readouts[]', readout do |form| %>
+  <%- tag.tr id: dom_id(readout.quantity, :new, :readout) do %>
+    <td>
+      <%# TODO: add grayed readout index (in separate column?) %>
+      <%= readout.quantity.relative_pathname(@superquantity) %>
+      <%= form.hidden_field :quantity_id %>
+    </td>
+    <td>
+      <%= form.number_field :value, required: true, autofocus: readout_counter == 0 %>
+    </td>
+    <td>
+      <%= form.collection_select :unit_id, @user_units, :id,
+        ->(u){ sanitize('&emsp;' * (u.base_id ? 1 : 0) + u.symbol) },
+        {prompt: '', disabled: '', selected: ''}, required: true %>
+    </td>
+    <td class="flex">
+      <%# TODO: change to _link_ after giving up displaying relative paths %>
+      <%= image_button_tag '', 'delete-outline', class: 'dangerous', name: nil,
+        formaction: discard_readouts_path(readout.quantity),
+        formmethod: :get, formnovalidate: true, data: {turbo_stream: true} %>
+    </td>
+  <% end %>
+<% end %>

app/views/readouts/_form_repath.html.erb

@@ -0,0 +1,7 @@
+<%= turbo_stream.update(:measurement_form_legend) { @superquantity&.pathname } %>
+
+<% @prev_quantities.each do |pq| %>
+  <%= turbo_stream.update dom_id(pq, nil, :pathname) do %>
+    <%= pq.relative_pathname(@superquantity) %>
+  <% end %>
+<% end %>

app/views/readouts/discard.turbo_stream.erb

@@ -0,0 +1,4 @@
+<%= turbo_stream.disable :create_measurement_button if @prev_quantities.one? %>
+<%= turbo_stream.remove dom_id(@quantity, :new, :readout) %>
+<%= render partial: 'form_repath' %>
+<%= turbo_stream.unselect dom_id(@quantity) %>

app/views/readouts/new.turbo_stream.erb

@@ -0,0 +1,8 @@
+<% @readouts.each do |r| %>
+  <%= turbo_stream.disable dom_id(r.quantity) %>
+<% end %>
+<%= render partial: 'form_repath' %>
+<%= turbo_stream.append :readouts do %>
+  <%= render partial: 'form', collection: @readouts, as: :readout %>
+<% end %>
+<%= turbo_stream.enable :create_measurement_button if @prev_quantities.empty? %>

app/views/units/_form.html.erb

@@ -1,5 +1,5 @@
 <%= tabular_fields_for @unit, form: form_tag do |form| %>
-  <%- tag.tr id: row, class: "form", onkeydown: "processKey(event)",
+  <%- tag.tr id: row, class: "form", onkeydown: "formProcessKey(event)",
     data: {link: link, form: form_tag, hidden_row: hidden_row} do %>
 
     <td style="--depth:<%= @unit.base_id? ? 1 : 0 %>">
@@ -8,11 +8,11 @@
     <td>
       <%= form.text_area :description, cols: 30, rows: 1, escape: false %>
     </td>
-    <td class="number">
+    <td>
-      <%= form.number_field :multiplier, required: true, size: 10, min: :step if @unit.base_id? %>
+      <%= form.number_field :multiplier, required: true if @unit.base_id? %>
     </td>
 
-    <td class="actions">
+    <td class="flex">
       <%= form.button %>
       <%= image_link_to t(:cancel), "close-outline", units_path, class: 'dangerous',
         name: :cancel, onclick: render_turbo_stream('form_close', {row: row}) %>

app/views/units/_unit.html.erb

@@ -6,14 +6,15 @@
                   drop_id: dom_id(unit.base || unit),
                   drop_id_param: "unit[base_id]"} do %>
 
-  <td class="link" style="--depth:<%= unit.base_id? ? 1 : 0 %>">
+  <td style="--depth:<%= unit.base_id? ? 1 : 0 %>">
-    <%= link_to unit, edit_unit_path(unit), onclick: 'this.blur();', data: {turbo_stream: true} %>
+    <%= link_to unit, edit_unit_path(unit), class: 'link', onclick: 'this.blur();',
+      data: {turbo_stream: true} %>
   </td>
   <td><%= unit.description %></td>
-  <td class="number"><%= unit.multiplier.to_html %></td>
+  <td class="ralign"><%= unit.multiplier.to_html if unit.base_id? %></td>
 
   <% if current_user.at_least(:active) %>
-    <td class="actions">
+    <td class="flex">
       <% unless unit.base_id? %>
         <%= image_link_to t('.new_subunit'), 'plus-outline', new_unit_path(unit),
           id: dom_id(unit, :new, :link), onclick: 'this.blur();', data: {turbo_stream: true} %>

app/views/units/index.html.erb

@@ -1,19 +1,21 @@
-<div class="rightside buttongrid">
+<div class="rightside-area buttongrid">
   <% if current_user.at_least(:active) %>
     <%= image_link_to t('.new_unit'), 'plus-outline', new_unit_path,
       id: dom_id(Unit, :new, :link), onclick: 'this.blur();', data: {turbo_stream: true} %>
   <% end %>
-  <%= image_link_to t('.import_units'), 'download-outline', default_units_path, class: 'tools' %>
+  <%= image_link_to t('.import_units'), 'download-outline', default_units_path,
+    class: 'tools-area' %>
 </div>
 
+<%# TODO: remove? form can be inserted directly, e.g. at the end of index %>
 <%= tag.div id: :unit_form %>
 
-<table class="main items">
+<table class="main-area items-table">
   <thead>
     <tr>
-      <th><%= User.human_attribute_name(:symbol).capitalize %></th>
+      <th><%= Unit.human_attribute_name(:symbol) %></th>
-      <th><%= User.human_attribute_name(:description).capitalize %></th>
+      <th class="hexpand"><%= Unit.human_attribute_name(:description) %></th>
-      <th><%= User.human_attribute_name(:multiplier).capitalize %></th>
+      <th><%= Unit.human_attribute_name(:multiplier) %></th>
       <% if current_user.at_least(:active) %>
         <th><%= t :actions %></th>
         <th></th>

app/views/units/rebase.turbo_stream.erb

@@ -1,4 +1,4 @@
 <%= turbo_stream.remove @unit %>
 <%= turbo_stream.replace @previous_base if @previous_base %>
-<%= turbo_stream.replace @unit.base if @unit.base_id? && (@previous_base.id != @unit.base_id) %>
+<%= turbo_stream.replace @unit.base if @unit.base_id? && (@previous_base&.id != @unit.base_id) %>
 <%= @before ? turbo_stream.before(@before, @unit) : turbo_stream.append(:units, @unit) %>

app/views/users/confirmations/create.turbo_stream.erb

@@ -0,0 +1 @@
+<% flash.discard %>

app/views/users/confirmations/new.html.erb

@@ -1,8 +0,0 @@
-<div class="main">
-  <%= labelled_form_for resource, url: user_confirmation_path do |f| %>
-    <%= f.email_field :email, required: true, size: 30, autofocus: true, autocomplete: "email",
-      value: (resource.pending_reconfirmation? ? resource.unconfirmed_email : resource.email) %>
-
-    <%= f.submit t(:resend_confirmation) %>
-  <% end %>
-</div>

app/views/users/index.html.erb

@@ -1,36 +1,34 @@
-<table class="main items" id="users">
+<table class="main-area items-table" id="users">
   <thead>
     <tr>
-      <th><%= User.human_attribute_name(:email).capitalize %></th>
+      <th><%= User.human_attribute_name(:email) %></th>
-      <th><%= User.human_attribute_name(:status).capitalize %></th>
+      <th><%= User.human_attribute_name(:status) %></th>
-      <th><%= User.human_attribute_name(:confirmed_at).capitalize %></th>
+      <th><%= User.human_attribute_name(:confirmed_at) %></th>
-      <th>
+      <th><%= User.human_attribute_name(:created_at) %>&nbsp;<sup>(UTC)</sup></th>
-        <%= User.human_attribute_name(:created_at).capitalize %>&nbsp;<sup>UTC</sup>
-      </th>
       <th><%= t :actions %></th>
     </tr>
   </thead>
   <tbody>
     <% @users.each do |user| %>
       <tr>
-        <td class="link"><%= link_to user, user_path(user) %></td>
+        <td><%= link_to user, user_path(user), class: 'link' %></td>
         <td>
           <% if user == current_user %>
             <%= user.status %>
           <% else %>
             <%= form_for user do |u| %>
-              <%= u.select :status, User.statuses.keys, {}, autocomplete: "off",
+              <%= u.select :status, User.statuses.keys, {}, autocomplete: 'off',
-                onchange: "this.form.requestSubmit();" %>
+                onchange: 'this.form.requestSubmit();' %>
             <% end %>
           <% end %>
         </td>
-        <td class="svg">
+        <td>
-          <%= svg_tag "pictograms/checkbox-marked-outline" if user.confirmed_at.present? %>
+          <%= svg_tag 'pictograms/checkbox-marked-outline' if user.confirmed_at.present? %>
         </td>
-        <td><%= user.created_at.to_fs(:db_without_sec) %></td>
+        <td><%= l user.created_at, format: :without_tz %></td>
-        <td class="actions">
+        <td class="flex">
           <% if allow_disguise?(user) %>
-            <%= image_link_to t(".disguise"), "incognito", disguise_user_path(user) %>
+            <%= image_link_to t('.disguise'), 'incognito', disguise_user_path(user) %>
           <% end %>
         </td>
       </tr>

app/views/users/mailer/confirmation_instructions.html.erb

@@ -1,5 +1,5 @@
 <p>Welcome <%= @email %>!</p>
 
 <p>You can confirm your account email through the link below:</p>
-
+<!-- FIXME: is confirmation_url valid route prefix? -->
 <p><%= link_to 'Confirm my account', confirmation_url(@resource, confirmation_token: @token) %></p>

app/views/users/passwords/create.turbo_stream.erb

@@ -0,0 +1,2 @@
+<%# For some reason flash messages are duplicated in bot flash and flash.now %>
+<% flash.discard %>

app/views/users/passwords/edit.html.erb

@@ -1,13 +1,12 @@
-<div class="main">
+<%= labeled_form_for resource, url: user_password_path,
-  <%= labelled_form_for resource, url: user_password_path, html: {method: :put} do |f| %>
+  html: {method: :put, class: 'main-area', data: {turbo: false}} do |f| %>
-    <%= f.hidden_field :reset_password_token, label: false %>
 
-    <%= f.password_field :password, label: t(".new_password"), required: true, size: 30,
+  <%= f.hidden_field :reset_password_token %>
-      minlength: @minimum_password_length, autofocus: true, autocomplete: "new-password",
-      hint: t("users.minimum_password_length", count: @minimum_password_length) %>
-    <%= f.password_field :password_confirmation, label: t(".password_confirmation"),
-      required: true, size: 30, minlength: @minimum_password_length, autocomplete: "off" %>
 
-    <%= f.submit t(".update_password") %>
+  <%= f.password_field :password, required: true, size: 30, autofocus: true,
-  <% end %>
+    minlength: @minimum_password_length, autocomplete: 'new-password' %>
-</div>
+  <%= f.password_field :password_confirmation, required: true, size: 30,
+    minlength: @minimum_password_length, autocomplete: 'off' %>
+
+  <%= f.submit t('.update_password') %>
+<% end %>

app/views/users/passwords/new.html.erb

@@ -1,7 +0,0 @@
-<div class="main">
-  <%= labelled_form_for resource, url: user_password_path do |f| %>
-    <%= f.email_field :email, required: true, size: 30, autofocus: true, autocomplete: "email" %>
-
-    <%= f.submit t(:recover_password) %>
-  <% end %>
-</div>

app/views/users/profiles/edit.html.erb

@@ -0,0 +1,30 @@
+<% content_for :navigation, flush: true do %>
+  <%= link_to svg_tag('pictograms/arrow-left-bold-outline', t(:back)),
+    request.referer.present? ? :back : root_path, class: 'tab' %>
+<% end %>
+
+<div class="rightside-area buttongrid">
+  <%#= TODO: Disallow/disable deletion for last admin account, image_button_to_if %>
+  <%= image_button_to t('.delete'), 'account-remove-outline', user_registration_path,
+    form_class: 'tools-area', method: :delete, data: {turbo: false},
+    onclick: {confirm: t('.confirm_delete')} %>
+</div>
+
+<%= labeled_form_for resource, url: registration_path(resource),
+  html: {method: :patch, class: 'main-area'} do |f| %>
+
+  <%= f.email_field :email, size: 30, autofocus: true, autocomplete: 'off' %>
+  <% if resource.pending_reconfirmation? %>
+    <%= f.text_field :unconfirmed_email, readonly: true,
+      confirmation_sent_at: l(resource.confirmation_sent_at) %>
+  <% end %>
+
+  <%= f.select :status, User.statuses, readonly: true %>
+
+  <%= f.password_field :password, size: 30, autocomplete: 'new-password',
+    minlength: @minimum_password_length %>
+  <%= f.password_field :password_confirmation, size: 30, autocomplete: 'off',
+    minlength: @minimum_password_length %>
+
+  <%= f.submit %>
+<% end %>

app/views/users/profiles/new.html.erb

@@ -0,0 +1,16 @@
+<%= labeled_form_for resource, url: user_registration_path,
+  html: {class: 'main-area', onsubmit: 'formValidate(event)'} do |f| %>
+
+  <%= f.email_field :email, required: true, size: 30, autofocus: true,
+    autocomplete: 'email' %>
+  <%= f.password_field :password, required: true, size: 30,
+    minlength: @minimum_password_length, autocomplete: 'new-password' %>
+  <%= f.password_field :password_confirmation, required: true, size: 30,
+    minlength: @minimum_password_length, autocomplete: 'off' %>
+
+  <%= f.submit t(:register), data: {turbo: false} %>
+
+  <%= image_button_tag t(:resend_confirmation), 'email-sync-outline',
+    class: 'auxiliary', formaction: user_confirmation_path, formnovalidate: true,
+    data: {validate: f.field_id(:email)} %>
+<% end %>

app/views/users/registrations/edit.html.erb

@@ -1,31 +0,0 @@
-<% content_for :navigation, flush: true do %>
-  <%= link_to svg_tag("pictograms/arrow-left-bold-outline", t(:back)),
-    request.referer.present? ? :back : root_path, class: 'tab' %>
-<% end %>
-
-<div class="rightside buttongrid">
-  <%= image_button_to t(".delete"), "account-remove-outline", user_registration_path,
-    form_class: 'tools', method: :delete, data: {turbo: false},
-    onclick: {confirm: t(".confirm_delete")} %>
-</div>
-
-<%= labelled_form_for resource, url: registration_path(resource),
-                      html: {method: :patch, class: 'main'} do |f| %>
-  <%= f.email_field :email, size: 30, autofocus: true, autocomplete: "off" %>
-  <% if f.object.pending_reconfirmation? %>
-    <%= f.text_field :unconfirmed_email, readonly: true, tabindex: -1,
-      hint: t(".unconfirmed_email_hint",
-              timestamp: f.object.confirmation_sent_at.to_fs(:db_without_sec)) %>
-  <% end %>
-
-  <%= f.select :status, User.statuses, readonly: true %>
-
-  <%= f.password_field :password, label: t(".new_password"), size: 30,
-    minlength: @minimum_password_length, autocomplete: "new-password",
-    hint: t(".blank_password_hint_html",
-            subhint: t("users.minimum_password_length", count: @minimum_password_length)) %>
-  <%= f.password_field :password_confirmation, label: t(".password_confirmation"),
-    size: 30, minlength: @minimum_password_length, autocomplete: "off" %>
-
-  <%= f.submit t(".update") %>
-<% end %>

app/views/users/registrations/new.html.erb

@@ -1,16 +0,0 @@
-<div class="main">
-  <%= labelled_form_for resource, url: user_registration_path do |f| %>
-    <%= f.email_field :email, required: true, size: 30, autofocus: true, autocomplete: "email" %>
-    <%= f.password_field :password, required: true, size: 30,
-      minlength: @minimum_password_length, autocomplete: "new-password",
-      hint: t("users.minimum_password_length", count: @minimum_password_length) %>
-    <%= f.password_field :password_confirmation, label: t(".password_confirmation"),
-      required: true, size: 30, minlength: @minimum_password_length, autocomplete: "off" %>
-
-    <%= f.submit t(:register) %>
-  <% end %>
-
-  <%= content_tag :p, t(:or), style: "text-align: center;" %>
-  <%= image_link_to t(:resend_confirmation), "email-sync-outline", new_user_confirmation_path,
-    class: "centered" %>
-</div>

app/views/users/sessions/new.html.erb

@@ -1,17 +1,19 @@
-<div class="main">
+<%= labeled_form_for resource, url: user_session_path,
-  <%= labelled_form_for resource, url: user_session_path do |f| %>
+  html: {class: 'main-area', onsubmit: 'formValidate(event)'} do |f| %>
-    <%= f.email_field :email, required: true, size: 30, autofocus: true, autocomplete: "email" %>
-    <%= f.password_field :password, required: true, size: 30, minlength: @minimum_password_length,
-      autocomplete: "current-password" %>
 
-    <% if devise_mapping.rememberable? %>
+  <%= f.email_field :email, required: true, size: 30, autofocus: true,
-      <%= f.check_box :remember_me, label: t(".remember_me") %>
+    autocomplete: 'email' %>
-    <% end %>
+  <%= f.password_field :password, required: true, size: 30,
+    autocomplete: 'current-password' %>
 
-    <%= f.submit t(:sign_in) %>
+  <% if devise_mapping.rememberable? %>
+    <%= f.check_box :remember_me %>
   <% end %>
 
-  <%= content_tag :p, t(:or), style: "text-align: center;" %>
+  <%# /sign_in as HTML; /password as TURBO_STREAM %>
-  <%= image_link_to t(:recover_password), 'lock-reset', new_user_password_path,
+  <%= f.submit t(:sign_in), data: {turbo: false} %>
-    class: 'centered' %>
+
-</div>
+  <%= image_button_tag t(:recover_password), 'lock-reset', class: 'auxiliary',
+    formaction: user_password_path, formnovalidate: true,
+    data: {validate: f.field_id(:email)} %>
+<% end %>

app/views/users/show.html.erb

@@ -1,19 +1,18 @@
 <% content_for :navigation, flush: true do %>
-  <div class="left">
+  <%= link_to svg_tag('pictograms/arrow-left-bold-outline', t(:back)), users_path,
-    <%= image_link_to t(:back), "arrow-left-bold-outline", users_path %>
+    class: 'tab' %>
-  </div>
 <% end %>
 
-<%= labelled_form_for @user do |f| %>
+<%= labeled_form_for @user, html: {class: 'main-area'} do |f| %>
   <%= f.email_field :email, readonly: true %>
-  <% if f.object.pending_reconfirmation? %>
+  <% if @user.pending_reconfirmation? %>
     <%= f.email_field :unconfirmed_email, readonly: true,
-      hint: t("users.registrations.edit.unconfirmed_email_hint",
+      confirmation_sent_at: l(@user.confirmation_sent_at) %>
-              timestamp: f.object.confirmation_sent_at.to_fs(:db_without_sec)) %>
   <% end %>
 
+  <%# TODO: allow status change here? %>
   <%= f.select :status, User.statuses, readonly: true %>
 
   <%= f.text_field :created_at, readonly: true %>
-  <%= f.text_field :confirmed_at, readonly: true %>
+  <%= f.text_field :confirmed_at, readonly: true, placeholder: t(:no) %>
 <% end %>

app/views/users/unlocks/new.html.erb

@@ -8,7 +8,7 @@
     <%= f.email_field :email, autofocus: true, autocomplete: "email" %>
   </div>
 
-  <div class="actions">
+  <div class="flex">
     <%= f.submit "Resend unlock instructions" %>
   </div>
 <% end %>

bin/ci

@@ -0,0 +1,6 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "active_support/continuous_integration"
+
+CI = ActiveSupport::ContinuousIntegration
+require_relative "../config/ci.rb"

bin/dev

@@ -0,0 +1,2 @@
+#!/usr/bin/env ruby
+exec "./bin/rails", "server", *ARGV

bin/setup

@@ -1,11 +1,10 @@
 #!/usr/bin/env ruby
 require "fileutils"
 
-# path to your application root.
 APP_ROOT = File.expand_path("..", __dir__)
 
 def system!(*args)
-  system(*args) || abort("\n== Command #{args} failed ==")
+  system(*args, exception: true)
 end
 
 FileUtils.chdir APP_ROOT do
@@ -14,7 +13,6 @@ FileUtils.chdir APP_ROOT do
   # Add necessary setup steps to this file.
 
   puts "== Installing dependencies =="
-  system! "gem install bundler --conservative"
   system("bundle check") || system!("bundle install")
 
   # puts "\n== Copying sample files =="
@@ -24,10 +22,14 @@ FileUtils.chdir APP_ROOT do
 
   puts "\n== Preparing database =="
   system! "bin/rails db:prepare"
+  system! "bin/rails db:reset" if ARGV.include?("--reset")
 
   puts "\n== Removing old logs and tempfiles =="
   system! "bin/rails log:clear tmp:clear"
 
-  puts "\n== Restarting application server =="
+  unless ARGV.include?("--skip-server")
-  system! "bin/rails restart"
+    puts "\n== Starting development server =="
+    STDOUT.flush # flush the output before exec(2) so that it displays
+    exec "bin/dev"
+  end
 end

config/application.rb.dist

@@ -18,14 +18,17 @@ require "rails/test_unit/railtie"
 # you've limited to :test, :development, or :production.
 Bundler.require(*Rails.groups)
 
+require_relative '../lib/default_settings_strategy'
+
 module FixinMe
   class Application < Rails::Application
     # Initialize configuration defaults for originally generated Rails version.
-    config.load_defaults 7.0
+    config.load_defaults 8.1
 
-    # Autoload lib/, required e.g. for core library extensions.
+    # Please, add to the `ignore` list any other `lib` subdirectories that do
-    # https://guides.rubyonrails.org/autoloading_and_reloading_constants.html#config-autoload-lib-ignore.
+    # not contain `.rb` files, or that should not be reloaded or eager loaded.
-    config.autoload_lib(ignore: %w(assets tasks))
+    # Common ones are `templates`, `generators`, or `middleware`, for example.
+    config.autoload_lib(ignore: %w[assets tasks])
 
     # Configuration for the application, engines, and railties goes here.
     #
@@ -38,16 +41,19 @@ module FixinMe
     config.action_dispatch.rescue_responses['ApplicationController::AccessForbidden'] = :forbidden
     config.action_dispatch.rescue_responses['ApplicationController::ParameterInvalid'] = :unprocessable_entity
 
+    # Set default migrations parameters.
+    config.active_record.migration_strategy = DefaultSettingsStrategy
+
     # SETUP: Below settings need to be updated on a per-installation basis.
     #
-    # URL to use in sent e-mails.
+    # Set host to be used by links generated in mailer templates.
-    config.action_mailer.default_url_options = {host: 'localhost', :protocol => 'https'}
+    config.action_mailer.default_url_options = {host: 'localhost', protocol: 'https'}
     # https://guides.rubyonrails.org/configuring.html#config-action-mailer-delivery-method
     config.action_mailer.delivery_method = :sendmail
 
     # List of hosts this app is available at.
     # https://guides.rubyonrails.org/configuring.html#actiondispatch-hostauthorization
-    config.hosts += ['localhost', 'example.com', IPAddr.new('1.2.3.4/32')]
+    config.hosts |= ['localhost']
 
     # Email address of admin account
     config.admin = 'admin@localhost'

config/ci.rb

@@ -0,0 +1,20 @@
+# Run using bin/ci
+
+CI.run do
+  step "Setup", "bin/setup --skip-server"
+
+  step "Security: Importmap vulnerability audit", "bin/importmap audit"
+  step "Tests: Rails", "bin/rails test"
+  step "Tests: Seeds", "env RAILS_ENV=test bin/rails db:seed:replant"
+
+  # Optional: Run system tests
+  # step "Tests: System", "bin/rails test:system"
+
+  # Optional: set a green GitHub commit status to unblock PR merge.
+  # Requires the `gh` CLI and `gh extension install basecamp/gh-signoff`.
+  # if success?
+  #   step "Signoff: All systems go. Ready for merge and deploy.", "gh signoff"
+  # else
+  #   failure "Signoff: CI failed. Do not merge or deploy.", "Fix the issues and try again."
+  # end
+end

config/database.yml.dist

@@ -24,27 +24,45 @@
 # Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
 # for a full overview on how database connection configuration can be specified.
 default: &default
-  adapter: mysql2
+  pool: <%= ENV.fetch('RAILS_MAX_THREADS', 3) %>
-  encoding: utf8mb4
+
-  collation: utf8mb4_0900_as_ci
+#mysql_default: &mysql_default
-  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+#  <<: *default
-  username: fixinme
+#  username: fixinme
-  password: Some-password1%
+#  password: Some-password1%
-  socket: /run/mysqld/mysqld.sock
+#  host: 127.0.0.1
+#  encoding: utf8mb4
+#  collation: utf8mb4_0900_as_ci
 
 production:
   <<: *default
-  database: fixinme
+  adapter: sqlite3
+  database: db/production.sqlite3
 
-# Unless you're planning on developing the application, you can skip
+# Unless you're planning on developing the application, you can skip/remove
 # configurations for development and test databases altogether.
 #development:
-#  <<: *default
+#  <<: *mysql_default
+#  adapter: mysql2
 #  database: fixinme_dev
 
-# Warning: The database defined as "test" will be erased and
+# Warning: The database(s) defined as "test" will be erased and
 # re-generated from your development database when you run "rake".
 # Do not set this db to the same as development or production.
 #test:
-#  <<: *default
+#  <<: *mysql_default
+#  adapter: mysql2
 #  database: fixinme_test
+
+# Multiple test databases can be provided. When more than one test db is
+# present, every test task (test, test:models, test:system, etc.) runs against
+# all of them.
+#test:
+#  mysql2:
+#    <<: *mysql_default
+#    adapter: mysql2
+#    database: fixinme_test
+#  sqlite3:
+#    <<: *default
+#    adapter: sqlite3
+#    database: db/test.sqlite3

config/environments/development.rb

@@ -3,10 +3,8 @@ require "active_support/core_ext/integer/time"
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
 
-  # In the development environment your application's code is reloaded any time
+  # Make code changes take effect immediately without server restart.
-  # it changes. This slows down response time but is perfect for development
+  config.enable_reloading = true
-  # since you don't have to restart the web server when you make code changes.
-  config.cache_classes = false
 
   # Do not eager load code on boot.
   config.eager_load = false
@@ -14,54 +12,52 @@ Rails.application.configure do
   # Show full error reports.
   config.consider_all_requests_local = true
 
-  # Enable server timing
+  # Enable server timing.
   config.server_timing = true
 
-  # Enable/disable caching. By default caching is disabled.
+  # Enable/disable Action Controller caching. By default Action Controller caching is disabled.
-  # Run rails dev:cache to toggle caching.
+  # Run rails dev:cache to toggle Action Controller caching.
   if Rails.root.join("tmp/caching-dev.txt").exist?
     config.action_controller.perform_caching = true
     config.action_controller.enable_fragment_cache_logging = true
-
+    config.public_file_server.headers = { "cache-control" => "public, max-age=#{2.days.to_i}" }
-    config.cache_store = :memory_store
-    config.public_file_server.headers = {
-      "Cache-Control" => "public, max-age=#{2.days.to_i}"
-    }
   else
     config.action_controller.perform_caching = false
-
-    config.cache_store = :null_store
   end
 
+  # Change to :null_store to avoid any caching.
+  config.cache_store = :memory_store
+
   # Don't care if the mailer can't send.
   config.action_mailer.raise_delivery_errors = false
 
+  # Make template changes take effect immediately.
   config.action_mailer.perform_caching = false
 
   # Print deprecation notices to the Rails logger.
   config.active_support.deprecation = :log
 
-  # Raise exceptions for disallowed deprecations.
-  config.active_support.disallowed_deprecation = :raise
-
-  # Tell Active Support which deprecation messages to disallow.
-  config.active_support.disallowed_deprecation_warnings = []
-
   # Raise an error on page load if there are pending migrations.
   config.active_record.migration_error = :page_load
 
   # Highlight code that triggered database queries in logs.
   config.active_record.verbose_query_logs = true
 
-  # Suppress logger output for asset requests.
+  # Append comments with runtime information tags to SQL queries in logs.
-  config.assets.quiet = true
+  config.active_record.query_log_tags_enabled = true
+
+  # Highlight code that enqueued background job in logs.
+  config.active_job.verbose_enqueue_logs = true
+
+  # Highlight code that triggered redirect in logs.
+  config.action_dispatch.verbose_redirect_logs = true
 
   # Raises error for missing translations.
   # config.i18n.raise_on_missing_translations = true
 
   # Annotate rendered view with file names.
-  # config.action_view.annotate_rendered_view_with_filenames = true
+  config.action_view.annotate_rendered_view_with_filenames = true
 
-  # Uncomment if you wish to allow Action Cable access from any origin.
+  # Raise error when a before_action's only/except options reference missing actions.
-  # config.action_cable.disable_request_forgery_protection = true
+  config.action_controller.raise_on_missing_callback_actions = true
 end

config/environments/production.rb

@@ -4,78 +4,83 @@ Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
 
   # Code is not reloaded between requests.
-  config.cache_classes = true
+  config.enable_reloading = false
 
-  # Eager load code on boot. This eager loads most of Rails and
+  # Eager load code on boot for better performance and memory savings (ignored by Rake tasks).
-  # your application in memory, allowing both threaded web servers
-  # and those relying on copy on write to perform better.
-  # Rake tasks automatically ignore this option for performance.
   config.eager_load = true
 
-  # Full error reports are disabled and caching is turned on.
+  # Full error reports are disabled.
-  config.consider_all_requests_local       = false
+  config.consider_all_requests_local = false
+
+  # Turn on fragment caching in view templates.
   config.action_controller.perform_caching = true
 
-  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # Cache assets for far-future expiry since they are all digest stamped.
-  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  config.public_file_server.headers = { "cache-control" => "public, max-age=#{1.year.to_i}" }
-  # config.require_master_key = true
-
-  # Disable serving static files from the `/public` folder by default since
-  # Apache or NGINX already handles this.
-  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
-
-  # Compress CSS using a preprocessor.
-  # config.assets.css_compressor = :sass
-
-  # Do not fallback to assets pipeline if a precompiled asset is missed.
-  config.assets.compile = false
 
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
   # config.asset_host = "http://assets.example.com"
 
-  # Specifies the header that your server uses for sending files.
+  # Assume all access to the app is happening through a SSL-terminating reverse proxy.
-  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  config.assume_ssl = true
-  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
 
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
-  # config.force_ssl = true
+  config.force_ssl = true
 
-  # Include generic and useful information about system operation, but avoid logging too much
+  # Skip http-to-https redirect for the default health check endpoint.
-  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  # config.ssl_options = { redirect: { exclude: ->(request) { request.path == "/up" } } }
-  config.log_level = :info
 
-  # Prepend all log lines with the following tags.
+  # Log to STDOUT with the current request id as a default log tag.
   config.log_tags = [ :request_id ]
+  config.logger   = ActiveSupport::TaggedLogging.logger(STDOUT)
 
-  # Use a different cache store in production.
+  # Change to "debug" to log everything (including potentially personally-identifiable information!).
+  config.log_level = ENV.fetch("RAILS_LOG_LEVEL", "info")
+
+  # Prevent health checks from clogging up the logs.
+  config.silence_healthcheck_path = "/up"
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Replace the default in-process memory cache store with a durable alternative.
   # config.cache_store = :mem_cache_store
 
-  config.action_mailer.perform_caching = false
+  # Replace the default in-process and non-durable queuing backend for Active Job.
+  # config.active_job.queue_adapter = :resque
 
   # Ignore bad email addresses and do not raise email delivery errors.
   # Set this to true and configure the email server for immediate delivery to raise delivery errors.
   # config.action_mailer.raise_delivery_errors = false
 
+  # Specify outgoing SMTP server. Remember to add smtp/* credentials via bin/rails credentials:edit.
+  # config.action_mailer.smtp_settings = {
+  #   user_name: Rails.application.credentials.dig(:smtp, :user_name),
+  #   password: Rails.application.credentials.dig(:smtp, :password),
+  #   address: "smtp.example.com",
+  #   port: 587,
+  #   authentication: :plain
+  # }
+
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
   # the I18n.default_locale when a translation cannot be found).
   config.i18n.fallbacks = true
 
-  # Don't log any deprecations.
-  config.active_support.report_deprecations = false
-
-  # Use default logging formatter so that PID and timestamp are not suppressed.
-  config.log_formatter = ::Logger::Formatter.new
-
-  # Use a different logger for distributed setups.
-  # require "syslog/logger"
-  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
-
-  if ENV["RAILS_LOG_TO_STDOUT"].present?
-    logger           = ActiveSupport::Logger.new(STDOUT)
-    logger.formatter = config.log_formatter
-    config.logger    = ActiveSupport::TaggedLogging.new(logger)
-  end
-
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
+
+  # Only use :id for inspections in production.
+  config.active_record.attributes_for_inspect = [ :id ]
+
+  # Enable DNS rebinding protection and other `Host` header attacks.
+  # config.hosts = [
+  #   "example.com",     # Allow requests from example.com
+  #   /.*\.example\.com/ # Allow requests from subdomains like `www.example.com`
+  # ]
+  #
+  # Skip DNS rebinding protection for the default health check endpoint.
+  # config.host_authorization = { exclude: ->(request) { request.path == "/up" } }
+
+  # Protect e-mail addresses from being logged only in production.
+  config.filter_parameters += [:email]
 end

config/environments/test.rb

@@ -1,5 +1,3 @@
-require "active_support/core_ext/integer/time"
-
 # The test environment is used exclusively to run your application's
 # test suite. You never need to work with it otherwise. Remember that
 # your test database is "scratch space" for the test suite and is wiped
@@ -8,54 +6,49 @@ require "active_support/core_ext/integer/time"
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
 
-  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  # While tests run files are not watched, reloading is not necessary.
-  config.cache_classes = true
+  config.enable_reloading = false
 
-  # Eager loading loads your whole application. When running a single test locally,
+  # Eager loading loads your entire application. When running a single test locally,
-  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # this is usually not necessary, and can slow down your test suite. However, it's
-  # system, or in some way before deploying your code.
+  # recommended that you enable it in continuous integration systems to ensure eager
+  # loading is working properly before deploying your code.
   config.eager_load = ENV["CI"].present?
 
-  # Configure public file server for tests with Cache-Control for performance.
+  # Configure public file server for tests with cache-control for performance.
-  config.public_file_server.enabled = true
+  config.public_file_server.headers = { "cache-control" => "public, max-age=3600" }
-  config.public_file_server.headers = {
-    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
-  }
 
-  # Hide full error reports.
+  # Behave as in `production`.
-  config.consider_all_requests_local     = false
+  config.consider_all_requests_local = false
-  # Render exception templates instead of raising exceptions.
-  config.action_dispatch.show_exceptions = :all
 
-  # Disable caching.
-  config.action_controller.perform_caching = false
   config.cache_store = :null_store
 
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false
 
-  config.action_mailer.perform_caching = false
-
   # Tell Action Mailer not to deliver emails to the real world.
   # The :test delivery method accumulates sent emails in the
   # ActionMailer::Base.deliveries array.
   config.action_mailer.delivery_method = :test
-  config.action_mailer.default_url_options = {host: '127.0.0.1', :protocol => 'http'}
+
+  # Set host to be used by links generated in mailer templates.
+  config.action_mailer.default_url_options = {host: Capybara.server_host,
+                                              protocol: 'http'}
 
   # Print deprecation notices to the stderr.
   config.active_support.deprecation = :stderr
 
-  # Raise exceptions for disallowed deprecations.
-  config.active_support.disallowed_deprecation = :raise
-
-  # Tell Active Support which deprecation messages to disallow.
-  config.active_support.disallowed_deprecation_warnings = []
-
   # Raises error for missing translations.
   config.i18n.raise_on_missing_translations = true
 
   # Annotate rendered view with file names.
   # config.action_view.annotate_rendered_view_with_filenames = true
 
+  # Raise error when a before_action's only/except options reference missing actions.
+  config.action_controller.raise_on_missing_callback_actions = true
+
+  # Allow Capybara application server IP
+  config.hosts |= [IPAddr.new(Capybara.server_host)]
+
   config.log_level = :info
 end

config/initializers/assets.rb

@@ -5,8 +5,3 @@ Rails.application.config.assets.version = "1.0"
 
 # Add additional assets to the asset load path.
 # Rails.application.config.assets.paths << Emoji.images_path
-
-# Precompile additional assets.
-# application.js, application.css, and all non-JS/CSS in the app/assets
-# folder are already added.
-Rails.application.config.assets.precompile += %w( '*.svg' )

config/initializers/content_security_policy.rb

@@ -16,9 +16,13 @@
 #     # policy.report_uri "/csp-violation-report-endpoint"
 #   end
 #
-#   # Generate session nonces for permitted importmap and inline scripts
+#   # Generate session nonces for permitted importmap, inline scripts, and inline styles.
 #   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
-#   config.content_security_policy_nonce_directives = %w(script-src)
+#   config.content_security_policy_nonce_directives = %w(script-src style-src)
+#
+#   # Automatically add `nonce` to `javascript_tag`, `javascript_include_tag`, and `stylesheet_link_tag`
+#   # if the corresponding directives are specified in `content_security_policy_nonce_directives`.
+#   # config.content_security_policy_nonce_auto = true
 #
 #   # Report violations without enforcing the policy.
 #   # config.content_security_policy_report_only = true

config/initializers/core_ext.rb

@@ -1,4 +1,6 @@
-require 'core_ext/big_decimal_scientific_notation'
+require 'core_ext/array_delete_bang'
+require 'core_ext/float'
+require 'core_ext/range'
 
 ActiveSupport.on_load :action_dispatch_system_test_case do
   prepend CoreExt::ActionDispatch::SystemTesting::TestHelpers::ScreenshotHelperUniqueId
@@ -9,9 +11,6 @@ ActiveSupport.on_load :action_view do
 end
 
 ActiveSupport.on_load :active_record do
-  ActiveModel::Validations::NumericalityValidator
-    .prepend CoreExt::ActiveModel::Validations::NumericalityValidatesPrecisionAndScale
-
   # Temporary patch for https://github.com/rails/rails/pull/54658
   Arel::TreeManager::StatementMethods
     .prepend CoreExt::Arel::TreeManager::StatementMethodsCteUpdateAndDelete

config/initializers/devise.rb

@@ -91,7 +91,7 @@ Devise.setup do |config|
   # It will change confirmation, password recovery and other workflows
   # to behave the same regardless if the e-mail provided was right or wrong.
   # Does not affect registerable.
-  # config.paranoid = true
+  config.paranoid = true
 
   # By default Devise will store the user in session. You can skip storage for
   # particular strategies by setting this option.
@@ -179,7 +179,7 @@ Devise.setup do |config|
 
   # ==> Configuration for :validatable
   # Range for password length.
-  config.password_length = 5..128
+  config.password_length = 5..32
 
   # Email regex used to validate email formats. It simply asserts that
   # one (and only one) @ exists in the given string. This is mainly

config/initializers/filter_parameter_logging.rb

@@ -1,8 +1,8 @@
 # Be sure to restart your server when you modify this file.
 
-# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# Configure parameters to be partially matched (e.g. passw matches password) and filtered from the log file.
-# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# Use this to limit dissemination of sensitive information.
-# notations and behaviors.
+# See the ActiveSupport::ParameterFilter documentation for supported notations and behaviors.
 Rails.application.config.filter_parameters += [
-  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn, :cvv, :cvc
 ]

config/initializers/time_formats.rb

@@ -1,3 +0,0 @@
-# Format contains non-breaking space:
-#   160.chr(Encoding::UTF_8)
-Time::DATE_FORMATS[:db_without_sec] = "%Y-%m-%d %H:%M"

config/initializers/turbo_streams_tag_builder.rb

@@ -19,7 +19,19 @@ ActiveSupport.on_load :turbo_streams_tag_builder do
     action :hide, target, allow_inferred_rendering: false
   end
 
+  def show(target)
+    action :show, target, allow_inferred_rendering: false
+  end
+
+  #def collapse(target)
+  #  action :collapse, target, allow_inferred_rendering: false
+  #end
+
   def close_form(target)
     action :close_form, target, allow_inferred_rendering: false
   end
+
+  def unselect(target)
+    action :unselect, target, allow_inferred_rendering: false
+  end
 end

config/locales/devise.en.yml

@@ -4,15 +4,15 @@ en:
   devise:
     confirmations:
       confirmed: "Your email address has been successfully confirmed."
-      send_instructions: "You will receive an email with instructions for how to confirm your email address in a few minutes."
+      send_paranoid_instructions: >
-      send_paranoid_instructions: "If your email address exists in our database, you will receive an email with instructions for how to confirm your email address in a few minutes."
+        If your email address is in our database, a message with instructions on how
+        to confirm your email address has been sent to you.
     failure:
       already_authenticated: "You are already signed in."
       inactive: "Your account is not activated yet."
-      invalid: "Invalid %{authentication_keys} or password."
+      invalid: "Invalid <b>%{authentication_keys}</b> or <b>password</b>."
       locked: "Your account is locked."
       last_attempt: "You have one more attempt before your account is locked."
-      not_found_in_database: "Invalid %{authentication_keys} or password."
       timeout: "Your session expired. Please sign in again to continue."
       unauthenticated: "You need to sign in or sign up before continuing."
       unconfirmed: "You have to confirm your email address before continuing."
@@ -32,8 +32,9 @@ en:
       success: "Successfully authenticated from %{kind} account."
     passwords:
       no_token: "You can't access this page without coming from a password reset email. If you do come from a password reset email, please make sure you used the full URL provided."
-      send_instructions: "You will receive an email with instructions on how to reset your password in a few minutes."
+      send_paranoid_instructions: >
-      send_paranoid_instructions: "If your email address exists in our database, you will receive a password recovery link at your email address in a few minutes."
+        If your email address is in our database, the password recovery link has been
+        sent to you.
       updated: "Your password has been changed successfully. You are now signed in."
       updated_not_active: "Your password has been changed successfully."
     registrations:
@@ -50,7 +51,6 @@ en:
       signed_out: "Signed out successfully."
       already_signed_out: "Signed out successfully."
     unlocks:
-      send_instructions: "You will receive an email with instructions for how to unlock your account in a few minutes."
       send_paranoid_instructions: "If your account exists, you will receive an email with instructions for how to unlock it in a few minutes."
       unlocked: "Your account has been unlocked successfully. Please sign in to continue."
   errors:

config/locales/en.yml

@@ -1,22 +1,24 @@
 en:
-  errors:
+  time:
-    messages:
+    formats:
-      precision_exceeded: must not exceed %{value} significant digits
+      # Format contains non-breaking space: 160.chr(Encoding::UTF_8)
-      scale_exceeded: must not exceed %{value} decimal digits
+      default: "%Y-%m-%d %H:%M %Z"
+      without_tz: "%Y-%m-%d %H:%M"
   activerecord:
     attributes:
-      unit:
+      quantity:
-        symbol: Symbol
+        description: Description
         name: Name
-        multiplier: Multiplier
+      unit:
         base: Base unit
+        description: Description
+        multiplier: Multiplier
+        symbol: Symbol
       user:
-        email: e-mail
+        confirmed_at: Confirmed
-        status: status
+        created_at: Registered
-        password: password
+        email: E-mail
-        created_at: registered
+        status: Status
-        confirmed_at: confirmed
-        unconfirmed_email: Awaiting confirmation for
     errors:
       models:
         unit:
@@ -53,9 +55,22 @@ en:
           The request is semantically incorrect and was rejected (422 Unprocessable Entity).
           This should not happen, please notify site administrator.
   helpers:
+    label:
+      user:
+        password_confirmation: 'Retype new password:'
+        password_length_hint_html:
+          count: '%{minimum_password_length}'
+          zero:
+          one: <br><em>(%{count} character minimum)</em>
+          other: <br><em>(%{count} characters minimum)</em>
+        remember_me: 'Remember me:'
+        unconfirmed_email_html: >
+          Awaiting confirmation for:<br><em>(since %{confirmation_sent_at})</em>
     submit:
       create: Create
       update: Update
+      user:
+        update: Update profile
   layouts:
     application:
       issue_tracker: Report issue
@@ -64,10 +79,12 @@ en:
       source_code: Get code
   measurements:
     navigation: Measurements
+    no_items: There are no measurements taken. You can Add some now.
+    form:
+      select_quantity: select quantities...
+      taken_at_html: Measurement taken at&emsp;
     index:
-      new_quantity: Selected
+      new_measurement: Add measurement
-      new_children: Children
-      new_subtree: Subtree
   quantities:
     navigation: Quantities
     no_items: There are no configured quantities. You can Add some or Import from defaults.
@@ -125,34 +142,27 @@ en:
       disguise: View as
     passwords:
       edit:
-        new_password: New password
+        password_html: 'New password:%{password_length_hint_html}'
-        password_confirmation: Retype new password
         update_password: Update password
-    registrations:
+    profiles:
       new:
-        password_confirmation: Retype password
+        password_html: 'Password:%{password_length_hint_html}'
+        password_confirmation: 'Retype password:'
       edit:
         confirm_delete: Are you sure you want to delete profile?
           All data will be irretrievably lost.
         delete: Delete profile
-        unconfirmed_email_hint: (since %{timestamp})
+        password_html: >
-        new_password: New password
+          New password:
-        password_confirmation: Retype new password
+          <br><em>leave blank to keep unchanged</em>
-        blank_password_hint_html: leave blank to keep unchanged<br>%{subhint}
+          %{password_length_hint_html}
-        update: Update profile
-    sessions:
-      new:
-        remember_me: Remember me
-    minimum_password_length:
-      zero:
-      one: (%{count} character minimum)
-      other: (%{count} characters minimum)
   actions: Actions
   add: Add
+  apply: Apply
   back: Back
   cancel: Cancel
   delete: Delete
-  or: or
+  :no: 'no'
   register: Register
   sign_in: Sign in
   recover_password: Recover password

config/puma.rb.dist

@@ -1,43 +1,41 @@
-# Puma can serve each request in a thread from an internal thread pool.
+# This configuration file will be evaluated by Puma. The top-level methods that
-# The `threads` method setting takes two numbers: a minimum and maximum.
+# are invoked here are part of Puma's configuration DSL. For more information
-# Any libraries that use thread pools should be configured to match
+# about methods provided by the DSL, see https://puma.io/puma/Puma/DSL.html.
-# the maximum value specified for Puma. Default is set to 5 threads for minimum
-# and maximum; this matches the default thread size of Active Record.
 #
-max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+# Puma starts a configurable number of processes (workers) and each process
-min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+# serves each request in a thread from an internal thread pool.
-threads min_threads_count, max_threads_count
-
-# Specifies the `worker_timeout` threshold that Puma will use to wait before
-# terminating a worker in development environments.
 #
-worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+# You can control the number of workers using ENV["WEB_CONCURRENCY"]. You
+# should only set this value when you want to run 2 or more workers. The
+# default is already 1.
+#
+# The ideal number of threads per worker depends both on how much time the
+# application spends waiting for IO operations and on how much you wish to
+# prioritize throughput over latency.
+#
+# As a rule of thumb, increasing the number of threads will increase how much
+# traffic a given process can handle (throughput), but due to CRuby's
+# Global VM Lock (GVL) it has diminishing returns and will degrade the
+# response time (latency) of the application.
+#
+# The default is set to 3 threads as it's deemed a decent compromise between
+# throughput and latency for the average Rails application.
+#
+# Any libraries that use a connection pool or another resource pool should
+# be configured to provide at least as many connections as the number of
+# threads. This includes Active Record's `pool` parameter in `database.yml`.
+threads_count = ENV.fetch("RAILS_MAX_THREADS", 3)
+threads threads_count, threads_count
 
 # Specifies the `port` that Puma will listen on to receive requests; default is 3000.
-#
+port ENV.fetch("PORT", 3000), '127.0.0.1'
-port ENV.fetch("PORT") { 3000 }
-
-# Specifies the `environment` that Puma will run in.
-#
-environment ENV.fetch("RAILS_ENV") { "development" }
-
-# Specifies the `pidfile` that Puma will use.
-pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
-
-# Specifies the number of `workers` to boot in clustered mode.
-# Workers are forked web server processes. If using threads and workers together
-# the concurrency of the application would be max `threads` * `workers`.
-# Workers do not work on JRuby or Windows (both of which do not support
-# processes).
-#
-# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
-
-# Use the `preload_app!` method when specifying a `workers` number.
-# This directive tells Puma to first boot the application and load code
-# before forking the application. This takes advantage of Copy On Write
-# process behavior so workers use less memory.
-#
-# preload_app!
 
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart
+
+# Run the Solid Queue supervisor inside of Puma for single-server deployments
+plugin :solid_queue if ENV["SOLID_QUEUE_IN_PUMA"]
+
+# Specify the PID file. Defaults to tmp/pids/server.pid in development.
+# In other environments, only set the PID file if requested.
+pidfile ENV["PIDFILE"] if ENV["PIDFILE"]

config/routes.rb

@@ -1,8 +1,8 @@
 Rails.application.routes.draw do
-  resources :measurements, path_names: {new: '/new(/:scope)'},
+  resources :measurements
-    constraints: {scope: /children|subtree/}, defaults: {scope: nil} do
 
-    get 'discard/:id', on: :new, action: :discard, as: :discard
+  resources :readouts, only: [:new] do
+    collection {get 'new/:id/discard', action: :discard, as: :discard}
   end
 
   resources :quantities, except: [:show], path_names: {new: '(/:id)/new'} do
@@ -15,7 +15,10 @@ Rails.application.routes.draw do
 
   namespace :default do
     resources :units, only: [:index, :destroy] do
-      member { post :import, :export }
+      member {
+        post :import
+        post :export
+      }
       #collection { post :import_all }
     end
   end
@@ -24,8 +27,9 @@ Rails.application.routes.draw do
   # https://github.com/heartcombo/devise/issues/5786
   connection = ActiveRecord::Base.connection
   if connection.schema_version && connection.table_exists?(:users)
+    # NOTE: change helper prefix from *_registration to *_profile once possible
     devise_for :users, path: '', path_names: {registration: 'profile'},
-      controllers: {registrations: :registrations}
+      controllers: {registrations: 'user/profiles'}
   end
 
   resources :users, only: [:index, :show, :update] do
@@ -34,9 +38,7 @@ Rails.application.routes.draw do
   end
 
   unauthenticated do
-    as :user do
+    root to: redirect('/sign_in')
-      root to: redirect('/sign_in')
-    end
   end
   root to: redirect('/units'), as: :user_root
 

db/migrate/20230309185340_create_users.rb

@@ -1,11 +1,11 @@
-class CreateUsers < ActiveRecord::Migration[7.0]
+class CreateUsers < ActiveRecord::Migration[8.1]
   def change
     create_table :users do |t|
       t.string :email, null: false, limit: 64
       t.integer :status, null: false, default: 0
 
-      t.timestamps null: false
+      t.timestamps
     end
-    add_index :users, :email, unique: true
+    add_index :users, :email
   end
 end

db/migrate/20230311220654_add_devise_to_users.rb

@@ -1,4 +1,4 @@
-class AddDeviseToUsers < ActiveRecord::Migration[7.0]
+class AddDeviseToUsers < ActiveRecord::Migration[8.1]
   def change
     change_table :users do |t|
       ## NOTE: commented fields left for reference/inclusion in future migrations
@@ -34,8 +34,8 @@ class AddDeviseToUsers < ActiveRecord::Migration[7.0]
       # t.integer :failed_attempts, default: 0, null: false 
     end
 
-    add_index :users, :reset_password_token, unique: true
+    add_index :users, :reset_password_token
-    add_index :users, :confirmation_token, unique: true
+    add_index :users, :confirmation_token
     # add_index :users, :unlock_token, unique: true
   end
 end

db/migrate/20230602185352_create_units.rb

@@ -1,14 +1,15 @@
-class CreateUnits < ActiveRecord::Migration[7.0]
+class CreateUnits < ActiveRecord::Migration[8.1]
   def change
     create_table :units do |t|
-      t.references :user, foreign_key: true
+      t.references :user, foreign_key: {on_delete: :cascade}
       t.string :symbol, null: false, limit: 15
       t.text :description
-      t.decimal :multiplier, null: false, precision: 30, scale: 15, default: 1.0
+      t.float :multiplier, null: false, limit: Float::MANT_DIG, default: 1.0
-      t.references :base, foreign_key: {to_table: :units}
+      t.references :base, foreign_key: {to_table: :units, on_delete: :cascade}
 
-      t.timestamps null: false
+      t.timestamps
     end
-    add_index :units, [:user_id, :symbol], unique: true
+    add_index :units, [:user_id, :symbol]
+    add_index :units, [:id, :user_id]
   end
 end

db/migrate/20250104194343_create_quantities.rb

@@ -1,17 +1,18 @@
-class CreateQuantities < ActiveRecord::Migration[7.2]
+class CreateQuantities < ActiveRecord::Migration[8.1]
   def change
     create_table :quantities do |t|
-      t.references :user, foreign_key: true
+      t.references :user, foreign_key: {on_delete: :cascade}
       t.string :name, null: false, limit: 31
       t.text :description
-      t.references :parent, foreign_key: {to_table: :quantities}
+      t.references :parent, foreign_key: {to_table: :quantities, on_delete: :cascade}
 
-      t.timestamps null: false
+      t.timestamps
 
       # Caches; can be computed from other attributes
       t.integer :depth, null: false, default: 0
       t.string :pathname, null: false, limit: 511
     end
-    add_index :quantities, [:user_id, :parent_id, :name], unique: true
+    add_index :quantities, [:user_id, :parent_id, :name]
+    add_index :quantities, [:id, :user_id]
   end
 end

db/migrate/20250121230456_create_readouts.rb

@@ -1,15 +1,69 @@
-class CreateReadouts < ActiveRecord::Migration[7.2]
+class CreateReadouts < ActiveRecord::Migration[8.1]
   def change
-    create_table :readouts do |t|
+    create_table :notes do |t|
-      t.references :user, null: false, foreign_key: true
+      t.text :text, null: false
-      t.references :quantity, null: false, foreign_key: true
+
-      t.references :unit, foreign_key: true
+      t.timestamps
-      t.decimal :value, null: false, precision: 30, scale: 15
+    end
+
+    create_table :measurements do |t|
+      t.datetime :taken_at, null: false
       #t.references :collector, foreign_key: true
       #t.references :device, foreign_key: true
+      t.references :note, foreign_key: {on_delete: :nullify}
 
-      t.timestamps null: false
+      t.timestamps
     end
-    add_index :readouts, [:quantity_id, :created_at], unique: true
+    add_index :measurements, :taken_at
+
+    # Defining Readouts as a super-/subclass polymorphic relations for different
+    # subclass data types (numeric, string, file) is not possible with proper
+    # referential integrity constraints. The required constraints are:
+    # * for every subclass record to have superclass record,
+    # * for every superclass record to have only one type of subclass record,
+    # * for every superclass record to have subclass record (unenforcable).
+    #   * this can be partially remedied by making superlass an abstract class in
+    #     Rails and disallow direct creation of records, but direct data
+    #     manipulation can still break referential integrity.
+    # Defining separate {Numeric,Text,File}_Readouts tables would make the
+    # unique index constraint unenforcable.
+    create_table :readouts do |t|
+      t.references :user, null: false, foreign_key: {on_delete: :cascade}
+      t.references :measurement, foreign_key: {on_delete: :cascade}
+      t.references :quantity, null: false, foreign_key: {on_delete: :cascade}
+      t.integer :category, null: false, default: 0
+      t.float :value, null: false, limit: Float::MANT_DIG
+      t.references :unit, null: false, foreign_key: {on_delete: :cascade}
+      # TODO: consider additional columns to allow wider range of value types
+      # t.text :text
+      # t.datetime :time
+      # t.references :file
+      # Possibly mutually exclusive with :unit or check constraint for:
+      #   :unit is not null <=> :value is not null
+
+      t.timestamps
+    end
+    add_index :readouts, [:measurement_id, :quantity_id, :category]
+    add_foreign_key :readouts, :quantities, column: [:quantity_id, :user_id],
+      primary_key: [:id, :user_id]
+    add_foreign_key :readouts, :units, column: [:unit_id, :user_id],
+      primary_key: [:id, :user_id]
+
+    # TODO: remove below tables after current setup verified
+    #create_table :numeric_values do |t|
+    #  t.references :readout, null: false, foreign_key: {on_delete: :cascade}
+    #  t.float :value, null: false, limit: Float::MANT_DIG
+    #  t.references :unit, null: false, foreign_key: {on_delete: :cascade}
+    #  # + generated, not stored column :value_type
+    #  # + foreign key constraint to readouts: [:readout_id, :value_id, :value_type]
+    #  # or 2 constraints: [:readout_id, :value_id], [:value_id, :value_type]
+    #  # if readouts.value_id needed, otherwise just one constraint:
+    #  # [:readout_id, :value_type]
+    #end
+
+    #create_table :string_values do |t|
+    #  t.references :readout, null: false, foreign_key: {on_delete: :cascade}
+    #  t.string :value, null: false, limit: 32
+    #end
   end
 end

db/schema.rb

@@ -10,7 +10,22 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
+ActiveRecord::Schema[8.1].define(version: 2025_01_21_230456) do
+  create_table "measurements", charset: "utf8mb4", collation: "utf8mb4_0900_as_ci", force: :cascade do |t|
+    t.datetime "taken_at", null: false
+    t.bigint "note_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["note_id"], name: "index_measurements_on_note_id"
+    t.index ["taken_at"], name: "index_measurements_on_taken_at", unique: true
+  end
+
+  create_table "notes", charset: "utf8mb4", collation: "utf8mb4_0900_as_ci", force: :cascade do |t|
+    t.text "text", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
   create_table "quantities", charset: "utf8mb4", collation: "utf8mb4_0900_as_ci", force: :cascade do |t|
     t.bigint "user_id"
     t.string "name", limit: 31, null: false
@@ -20,6 +35,7 @@ ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
     t.datetime "updated_at", null: false
     t.integer "depth", default: 0, null: false
     t.string "pathname", limit: 511, null: false
+    t.index ["id", "user_id"], name: "index_quantities_on_id_and_user_id", unique: true
     t.index ["parent_id"], name: "index_quantities_on_parent_id"
     t.index ["user_id", "parent_id", "name"], name: "index_quantities_on_user_id_and_parent_id_and_name", unique: true
     t.index ["user_id"], name: "index_quantities_on_user_id"
@@ -27,13 +43,18 @@ ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
 
   create_table "readouts", charset: "utf8mb4", collation: "utf8mb4_0900_as_ci", force: :cascade do |t|
     t.bigint "user_id", null: false
+    t.bigint "measurement_id"
     t.bigint "quantity_id", null: false
-    t.bigint "unit_id"
+    t.integer "category", default: 0, null: false
-    t.decimal "value", precision: 30, scale: 15, null: false
+    t.float "value", limit: 53, null: false
+    t.bigint "unit_id", null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.index ["quantity_id", "created_at"], name: "index_readouts_on_quantity_id_and_created_at", unique: true
+    t.index ["measurement_id", "quantity_id", "category"], name: "index_readouts_on_measurement_id_and_quantity_id_and_category", unique: true
+    t.index ["measurement_id"], name: "index_readouts_on_measurement_id"
+    t.index ["quantity_id", "user_id"], name: "fk_rails_9d92eaafc6"
     t.index ["quantity_id"], name: "index_readouts_on_quantity_id"
+    t.index ["unit_id", "user_id"], name: "fk_rails_348b0fb4c5"
     t.index ["unit_id"], name: "index_readouts_on_unit_id"
     t.index ["user_id"], name: "index_readouts_on_user_id"
   end
@@ -42,11 +63,12 @@ ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
     t.bigint "user_id"
     t.string "symbol", limit: 15, null: false
     t.text "description"
-    t.decimal "multiplier", precision: 30, scale: 15, default: "1.0", null: false
+    t.float "multiplier", limit: 53, default: 1.0, null: false
     t.bigint "base_id"
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.index ["base_id"], name: "index_units_on_base_id"
+    t.index ["id", "user_id"], name: "index_units_on_id_and_user_id", unique: true
     t.index ["user_id", "symbol"], name: "index_units_on_user_id_and_symbol", unique: true
     t.index ["user_id"], name: "index_units_on_user_id"
   end
@@ -69,11 +91,15 @@ ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
     t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
   end
 
-  add_foreign_key "quantities", "quantities", column: "parent_id"
+  add_foreign_key "measurements", "notes", on_delete: :nullify
-  add_foreign_key "quantities", "users"
+  add_foreign_key "quantities", "quantities", column: "parent_id", on_delete: :cascade
-  add_foreign_key "readouts", "quantities"
+  add_foreign_key "quantities", "users", on_delete: :cascade
-  add_foreign_key "readouts", "units"
+  add_foreign_key "readouts", "measurements", on_delete: :cascade
-  add_foreign_key "readouts", "users"
+  add_foreign_key "readouts", "quantities", column: ["quantity_id", "user_id"], primary_key: ["id", "user_id"]
-  add_foreign_key "units", "units", column: "base_id"
+  add_foreign_key "readouts", "quantities", on_delete: :cascade
-  add_foreign_key "units", "users"
+  add_foreign_key "readouts", "units", column: ["unit_id", "user_id"], primary_key: ["id", "user_id"]
+  add_foreign_key "readouts", "units", on_delete: :cascade
+  add_foreign_key "readouts", "users", on_delete: :cascade
+  add_foreign_key "units", "units", column: "base_id", on_delete: :cascade
+  add_foreign_key "units", "users", on_delete: :cascade
 end

db/seeds.rb

@@ -7,17 +7,21 @@
 User.transaction do
   break if User.find_by status: :admin
 
-  User.create! email: Rails.configuration.admin, password: 'admin', status: :admin do |user|
+  email = Rails.configuration.admin
+  password_length = SecureRandom.rand(Rails.configuration.devise.password_length)
+  password = SecureRandom.alphanumeric(password_length)
+
+  User.create!(email: email, password: password, status: :admin) do |user|
     user.skip_confirmation!
-    print "Creating #{user.status} account '#{user.email}' with password '#{user.password}'..."
+    print "Creating #{user.status} account '#{user.email}'" \
+      " with password '#{user.password}'..."
   end
   puts "done."
-
 rescue ActiveRecord::RecordInvalid => exception
-  puts "failed. #{exception.message}"
+  puts "failed.", exception.message
 end
 
 # Formulas will be deleted as dependent on Quantities
 #[Source, Quantity, Unit].each { |model| model.defaults.delete_all }
 
-require_relative 'seeds/units.rb'
+load "db/seeds/units.rb"

db/seeds/templates/units.erb

@@ -1,10 +1,10 @@
 Unit.transaction do
-  Unit.defaults.order(Unit.arel_table[:base_id].eq(nil)).delete_all
+  Unit.defaults.delete_all
   units = {}
 <% Unit.defaults.ordered.each do |unit| %>
 <%= "\n" if unit.base.nil? %>
   units['<%= unit.symbol %>'] =
-    Unit.create symbol: '<%= unit.symbol %>',<% unless unit.base.nil? %> base: units['<%= unit.base.symbol %>'], multiplier: '<%= unit.multiplier.to_scientific %>',<% end %>
+    Unit.create symbol: '<%= unit.symbol %>',<% if unit.base_id? %> base: units['<%= unit.base.symbol %>'], multiplier: '<%= unit.multiplier.to_scientific %>',<% end %>
                 description: '<%= unit.description %>'
 <% end %>
 end

db/seeds/units.rb

@@ -1,5 +1,5 @@
 Unit.transaction do
-  Unit.defaults.order(Unit.arel_table[:base_id].eq(nil)).delete_all
+  Unit.defaults.delete_all
 
   units = {}
 

db/sqlite3_schema.rb

@@ -0,0 +1,103 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[8.1].define(version: 2025_01_21_230456) do
+  create_table "measurements", force: :cascade do |t|
+    t.datetime "taken_at", null: false
+    t.integer "note_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["note_id"], name: "index_measurements_on_note_id"
+    t.index ["taken_at"], name: "index_measurements_on_taken_at", unique: true
+  end
+
+  create_table "notes", force: :cascade do |t|
+    t.text "text", limit: 65535, null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
+  create_table "quantities", force: :cascade do |t|
+    t.integer "user_id"
+    t.string "name", limit: 31, null: false
+    t.text "description", limit: 65535
+    t.integer "parent_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.integer "depth", default: 0, null: false
+    t.string "pathname", limit: 511, null: false
+    t.index ["id", "user_id"], name: "index_quantities_on_id_and_user_id", unique: true
+    t.index ["parent_id"], name: "index_quantities_on_parent_id"
+    t.index ["user_id", "parent_id", "name"], name: "index_quantities_on_user_id_and_parent_id_and_name", unique: true
+    t.index ["user_id"], name: "index_quantities_on_user_id"
+  end
+
+  create_table "readouts", force: :cascade do |t|
+    t.integer "user_id", null: false
+    t.integer "measurement_id"
+    t.integer "quantity_id", null: false
+    t.integer "category", default: 0, null: false
+    t.float "value", limit: 53, null: false
+    t.integer "unit_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["measurement_id", "quantity_id", "category"], name: "index_readouts_on_measurement_id_and_quantity_id_and_category", unique: true
+    t.index ["measurement_id"], name: "index_readouts_on_measurement_id"
+    t.index ["quantity_id"], name: "index_readouts_on_quantity_id"
+    t.index ["unit_id"], name: "index_readouts_on_unit_id"
+    t.index ["user_id"], name: "index_readouts_on_user_id"
+  end
+
+  create_table "units", force: :cascade do |t|
+    t.integer "user_id"
+    t.string "symbol", limit: 15, null: false
+    t.text "description", limit: 65535
+    t.float "multiplier", limit: 53, default: 1.0, null: false
+    t.integer "base_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["base_id"], name: "index_units_on_base_id"
+    t.index ["id", "user_id"], name: "index_units_on_id_and_user_id", unique: true
+    t.index ["user_id", "symbol"], name: "index_units_on_user_id_and_symbol", unique: true
+    t.index ["user_id"], name: "index_units_on_user_id"
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "email", limit: 64, null: false
+    t.integer "status", default: 0, null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.string "encrypted_password", default: "", null: false
+    t.string "reset_password_token"
+    t.datetime "reset_password_sent_at"
+    t.datetime "remember_created_at"
+    t.string "confirmation_token"
+    t.datetime "confirmed_at"
+    t.datetime "confirmation_sent_at"
+    t.string "unconfirmed_email", limit: 64
+    t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
+    t.index ["email"], name: "index_users_on_email", unique: true
+    t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
+  end
+
+  add_foreign_key "measurements", "notes", on_delete: :nullify
+  add_foreign_key "quantities", "quantities", column: "parent_id", on_delete: :cascade
+  add_foreign_key "quantities", "users", on_delete: :cascade
+  add_foreign_key "readouts", "measurements", on_delete: :cascade
+  add_foreign_key "readouts", "quantities", column: ["quantity_id", "user_id"], primary_key: ["id", "user_id"]
+  add_foreign_key "readouts", "quantities", on_delete: :cascade
+  add_foreign_key "readouts", "units", column: ["unit_id", "user_id"], primary_key: ["id", "user_id"]
+  add_foreign_key "readouts", "units", on_delete: :cascade
+  add_foreign_key "readouts", "users", on_delete: :cascade
+  add_foreign_key "units", "units", column: "base_id", on_delete: :cascade
+  add_foreign_key "units", "users", on_delete: :cascade
+end

lib/core_ext/active_model/validations/numericality_validates_precision_and_scale.rb

@@ -1,19 +0,0 @@
-module CoreExt::ActiveModel::Validations::NumericalityValidatesPrecisionAndScale
-  def validate_each(record, attr_name, value, ...)
-    super(record, attr_name, value, ...)
-
-    if options[:precision] || options[:scale]
-      attr_type = record.class.type_for_attribute(attr_name)
-      # For conversion of 'value' to BigDecimal 'ndigits' is not supplied intentionally,
-      # to avoid silent rounding. It is only required for conversion from Float and
-      # Rational, which should not happen.
-      value = BigDecimal(value) unless value.is_a? BigDecimal
-      if options[:precision] && (value.precision > attr_type.precision)
-        record.errors.add(attr_name, :precision_exceeded, **filtered_options(attr_type.precision))
-      end
-      if options[:scale] && (value.scale > attr_type.scale)
-        record.errors.add(attr_name, :scale_exceeded, **filtered_options(attr_type.scale))
-      end
-    end
-  end
-end

lib/core_ext/array_delete_bang.rb

@@ -0,0 +1,10 @@
+module CoreExt
+  module ArrayDeleteBang
+    def delete!(obj)
+      self.delete(obj)
+      self
+    end
+  end
+end
+
+Array.prepend CoreExt::ArrayDeleteBang

lib/core_ext/big_decimal_scientific_notation.rb

@@ -1,36 +0,0 @@
-module CoreExt
-  module BigDecimalScientificNotation
-    def to_scientific
-      return 'NaN' unless finite?
-
-      sign, coefficient, base, exponent = split
-      (sign == -1 ? '-' : '') +
-        (coefficient.length > 1 ? coefficient.insert(1, '.') : coefficient) +
-        (exponent != 1 ? "e#{exponent-1}" : '')
-    end
-
-    # Converts value to HTML formatted scientific notation
-    def to_html
-      sign, coefficient, base, exponent = split
-      return 'NaN' unless sign
-
-      result = (sign == -1 ? '-' : '')
-      unless coefficient == '1' && sign == 1
-        if coefficient.length > 1
-          result += coefficient.insert(1, '.')
-        elsif
-          result += coefficient
-        end
-        if exponent != 1
-          result += "×"
-        end
-      end
-      if exponent != 1
-        result += "10<sup>% d</sup>" % [exponent-1]
-      end
-      result.html_safe
-    end
-  end
-end
-
-BigDecimal.prepend CoreExt::BigDecimalScientificNotation

lib/core_ext/float.rb

@@ -0,0 +1,54 @@
+# If a decimal string with at most 15 significant digits is converted to the
+# IEEE 754 double-precision format, giving a normal number, and then converted
+# back to a decimal string with the same number of digits, the final result
+# should match the original string.
+# If an IEEE 754 double-precision number is converted to a decimal string with
+# at least 17 significant digits, and then converted back to double-precision
+# representation, the final result must match the original number:
+#   ("%.16e" % self).to_f == self
+class Float
+  def to_scientific
+    sign, significand, exponent = split
+    sign + significand + (exponent != 0 ? "e#{exponent}" : '')
+  end
+
+  # Converts value to HTML formatted scientific notation.
+  def to_html(show_unity: true)
+    result, significand, exponent = split
+    result += significand if significand != '1' || (exponent == 0 && show_unity)
+    if exponent != 0
+      result += "×" if significand != '1'
+      result += "10<sup>% d</sup>" % exponent
+    end
+    result.html_safe
+  end
+
+  # Assume #finite? is true.
+  def limit(precision = DIG)
+    return 0.0 if precision.zero?
+    sign, significand, exponent = split(DIG_MAX)
+    "#{sign}#{significand[..precision]}e#{exponent}".to_f
+  end
+
+  private
+
+  SPLIT_FLOAT = /(-?)(.*?)\.?0*e(.*)/
+
+  # Format `%e` displays starting from significant digit (not 0).
+  def split(digits = DIG)
+    return ['', to_s[..2], 0] unless finite?
+    return ['', '0', 0] if digits.zero?
+    ("%.#{digits - 1}e" % self).match(SPLIT_FLOAT).captures
+      .then { |sign, significand, exponent| [sign, significand, exponent.to_i] }
+  end
+
+  # The maximum number of significant decimal digits in a double-precision
+  # floating point number.
+  DIG_MAX = 17
+  # Smallest and largest double-precision floating point numbers with DIG
+  # precision.
+  # TODO: change MIN_15 to MIN.ceil(MIN_10_EXP - DIG) after #ceil fix in Ruby
+  # v4.0.5: https://bugs.ruby-lang.org/issues/22079
+  MIN_15 = MIN.ceil(-(MIN_10_EXP - 1))
+  MAX_15 = MAX.floor(-(MAX_10_EXP - DIG + 1))
+end

lib/core_ext/range.rb

@@ -0,0 +1,31 @@
+class Range
+  # TODO: cleanup comments after commit
+  # * < nil, true < false
+  #if a.end == b.end
+  #  a.exclude_end? ^ b.exclude_end? ? (a.exclude_end? ? -1 : 1) : 0
+  #else
+  #  a.end <=> b.end || (a.end.nil? ? 1 : -1)
+  #end
+  #a.end == b.end ? (b.exclude_end? ? b : a) : [a, b].to_h.except(nil).min
+  #*(l[0] == r[0] ? (r[1] ? r : l) : [l, r].reject{ |e| e[0].nil? }.min)
+  def &(other)
+    case other
+    when Range
+      return nil unless self.overlap?(other)
+
+      both = [self, other]
+      return Range.new(
+        both.map(&:begin).compact.max,
+        *if self.end == other.end
+           other.exclude_end? ? [other] : [self]
+        else
+          both.select(&:end)
+        end.map { |r| [r.end, r.exclude_end?] }.min
+      )
+    when Array
+      return other.map { |o| self & o }.compact
+    else
+      return self.member?(other) ? other : nil
+    end
+  end
+end

lib/default_settings_strategy.rb

@@ -0,0 +1,55 @@
+class DefaultSettingsStrategy < ActiveRecord::Migration::DefaultStrategy
+  COLUMN_DEFAULTS = {
+    # TODO: all types `null: false` ?
+    # TODO: references `foreign_key: {on_delete: :cascade}` ?
+    # `timestamps` - Rails defaults to `null: false, precision: true`.
+    # `limit:` for `text` - `text` can be theoretically up to 1GB or
+    #   longer, so roughly unlimited for practical purposes. But:
+    #   * the actual usable length depends on additional factors, like compile
+    #     time limits (`SQLITE_MAX_LENGTH` in SQLite), runtime settings
+    #     (`max_allowed_packet` in MySQL) and probably other,
+    #   * Rails does not report limit for `text` column types, unless it is
+    #     explicitly set.
+    #   The decision is to always set safe limit and enforce it by validations, to
+    #   avoid surprises (e.g. text truncation) when saving to dabatase.
+    text: {limit: 2**16 - 1}
+  }
+  COLUMN_DEFAULTS.default = {}
+  COLUMN_DEFAULTS.freeze
+
+  module ColumnSettingsStrategy
+    def column(name, type, **options)
+      super(name, type, **COLUMN_DEFAULTS[type].merge(options))
+    end
+  end
+  ActiveRecord::ConnectionAdapters::TableDefinition.prepend ColumnSettingsStrategy
+
+  # `force: :cascade` - does nothing on MySQL, so `force:` is useless.
+  # `if_not_exists: true`/`if_exists: true` - without these options it's impossible
+  #   to change migration status once migration fails partially. If `up` migration
+  #   creates some, but not all objects, its status is not updated from `down` to
+  #   `up`. Then it's impossible to migrate: a) up - due to `already exists`
+  #   errors and b) down - due to migration status.
+  MIGRATION_DEFAULTS = {
+    add_check_constraint: {if_not_exists: true},
+    add_column:           {if_not_exists: true},
+    add_foreign_key:      {if_not_exists: true},
+    add_index:            {if_not_exists: true, unique: true},
+    add_timestamps:       {if_not_exists: true},
+    create_table:         {if_not_exists: true},
+    drop_table:               {if_exists: true},
+    remove_check_constraint:  {if_exists: true},
+    remove_column:            {if_exists: true},
+    remove_foreign_key:       {if_exists: true},
+    remove_index:             {if_exists: true},
+    remove_timestamps:        {if_exists: true},
+  }
+  MIGRATION_DEFAULTS.default = {}
+  MIGRATION_DEFAULTS.freeze
+
+  def method_missing(method, *args, **kwargs, &)
+    conflicts = kwargs.has_key?(:force) ? [:if_not_exists, :if_exists] : []
+    defaults = MIGRATION_DEFAULTS[method.to_sym].except(*conflicts)
+    super(method, *args, **defaults.merge(kwargs), &)
+  end
+end

public/icon.svg

@@ -0,0 +1,3 @@
+<svg width="512" height="512" xmlns="http://www.w3.org/2000/svg">
+  <circle cx="256" cy="256" r="256" fill="red"/>
+</svg>

test/application_system_test_case.rb

@@ -1,7 +1,7 @@
 require "test_helper"
 
 class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
-  extend ActionView::Helpers::TranslationHelper
+  include ActionView::Helpers::SanitizeHelper
   include ActionView::Helpers::UrlHelper
 
   # NOTE: geckodriver installed with Firefox, ignore incompatibility warning
@@ -17,17 +17,54 @@ class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
     options.add_preference('browser.download.dir', "#{Rails.root}/tmp/")
   end
 
-  def sign_in(user: users.select(&:confirmed?).sample, password: randomize_user_password!(user))
+  def sign_in(user: users.select(&:confirmed?).sample,
+              password: randomize_user_password!(user))
     visit new_user_session_url
-    fill_in User.human_attribute_name(:email).capitalize, with: user.email
+    fill_in User.human_attribute_name(:email), with: user.email
-    fill_in User.human_attribute_name(:password).capitalize, with: password
+    fill_in User.human_attribute_name(:password), with: password
     click_on t(:sign_in)
+    yield if block_given?
     user
   end
 
-  def inject_button_to(after, *button_options)
+  def inject_button_to(inside, *button_options)
     button = button_to *button_options
-    evaluate_script("arguments[0].insertAdjacentHTML('beforeend', '#{button.html_safe}');", after)
+    inside.evaluate_script("this.insertAdjacentHTML('beforeend', arguments[0]);",
+                           button.html_safe)
+  end
+
+  # Allow skipping interpolations when translating for testing purposes
+  INTERPOLATION_PATTERNS = Regexp.union(I18n.config.interpolation_patterns)
+  def translate(key, **options)
+    translation = options.empty? ? super.split(INTERPOLATION_PATTERNS, 2).first : super
+    sanitize(translation, tags: [])
+  end
+  alias :t :translate
+
+  DB_CONFIGS = ActiveRecord::Base.configurations.configs_for(env_name: "test")
+  TEST_CONFIGS = Hash.new(DB_CONFIGS.first.name.to_sym)
+  class << self
+    # NOTE: alternative to current solution is to create shards:
+    #   ActiveRecord::Base.connects_to(
+    #     shards: {mysql2: {writing: :mysql2}, sqlite3: {writing: :sqlite3}}
+    #   )
+    # and use them in one of the following ways:
+    # * set config.active_record.shard_selector/shard_resolver
+    # * run tests within: ActiveRecord::Base.connected_to(shard: :sqlite3) { test_ }
+    # Remove this note once current solution is confirmed to work.
+    #
+    # Test block should not be modified here, as it would change its binding from
+    # instance level to class level.
+    if DB_CONFIGS.many?
+      def test(name, ...)
+        DB_CONFIGS.each do |config|
+          TEST_CONFIGS[super("#{config.name} #{name}", ...)] = config.name.to_sym
+        end
+      end
+    end
+  end
+  setup do
+    ActiveRecord::Base.establish_connection(TEST_CONFIGS[name.to_sym])
   end
 
   #def assert_stale(element)