Fix test passing blank input into required field

SQLite3::SQLException: circular reference

.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

@@ -32,3 +32,14 @@ whenever a change is considered, to avoid regressions.
     * as a standard with hardware implementations ensures both: computing
       efficiency and hardware/3rd party library compatibility as opposed to Ruby
       custom `BigDecimal` type
+
+### 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", "~> 7.2.3"
+# 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
@@ -42,11 +46,4 @@ group :test do
   # Use system testing [https://guides.rubyonrails.org/testing.html#system-testing]
   gem "capybara"
   gem "selenium-webdriver"
-
-  # Remove minitest version restriction after error fixed:
-  #   railties-7.2.3/lib/rails/test_unit/line_filtering.rb:7:in `run':
-  #     wrong number of arguments (given 3, expected 1..2) (ArgumentError)
-  #   from /var/www/.gem/ruby/3.3.0/gems/minitest-6.0.2/lib/minitest.rb:473:in
-  #     `block (2 levels) in run_suite'
-  gem "minitest", "< 6"
 end

Gemfile.lock

@@ -1,85 +1,85 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    actioncable (7.2.3)
+    action_text-trix (2.1.18)
-      actionpack (= 7.2.3)
+      railties
-      activesupport (= 7.2.3)
+    actioncable (8.1.3)
+      actionpack (= 8.1.3)
+      activesupport (= 8.1.3)
       nio4r (~> 2.0)
       websocket-driver (>= 0.6.1)
       zeitwerk (~> 2.6)
-    actionmailbox (7.2.3)
+    actionmailbox (8.1.3)
-      actionpack (= 7.2.3)
+      actionpack (= 8.1.3)
-      activejob (= 7.2.3)
+      activejob (= 8.1.3)
-      activerecord (= 7.2.3)
+      activerecord (= 8.1.3)
-      activestorage (= 7.2.3)
+      activestorage (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       mail (>= 2.8.0)
-    actionmailer (7.2.3)
+    actionmailer (8.1.3)
-      actionpack (= 7.2.3)
+      actionpack (= 8.1.3)
-      actionview (= 7.2.3)
+      actionview (= 8.1.3)
-      activejob (= 7.2.3)
+      activejob (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       mail (>= 2.8.0)
       rails-dom-testing (~> 2.2)
-    actionpack (7.2.3)
+    actionpack (8.1.3)
-      actionview (= 7.2.3)
+      actionview (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
-      cgi
       nokogiri (>= 1.8.5)
-      racc
+      rack (>= 2.2.4)
-      rack (>= 2.2.4, < 3.3)
       rack-session (>= 1.0.1)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
       useragent (~> 0.16)
-    actiontext (7.2.3)
+    actiontext (8.1.3)
-      actionpack (= 7.2.3)
+      action_text-trix (~> 2.1.15)
-      activerecord (= 7.2.3)
+      actionpack (= 8.1.3)
-      activestorage (= 7.2.3)
+      activerecord (= 8.1.3)
-      activesupport (= 7.2.3)
+      activestorage (= 8.1.3)
+      activesupport (= 8.1.3)
       globalid (>= 0.6.0)
       nokogiri (>= 1.8.5)
-    actionview (7.2.3)
+    actionview (8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       builder (~> 3.1)
-      cgi
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
-    activejob (7.2.3)
+    activejob (8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       globalid (>= 0.3.6)
-    activemodel (7.2.3)
+    activemodel (8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
-    activerecord (7.2.3)
+    activerecord (8.1.3)
-      activemodel (= 7.2.3)
+      activemodel (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       timeout (>= 0.4.0)
-    activestorage (7.2.3)
+    activestorage (8.1.3)
-      actionpack (= 7.2.3)
+      actionpack (= 8.1.3)
-      activejob (= 7.2.3)
+      activejob (= 8.1.3)
-      activerecord (= 7.2.3)
+      activerecord (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       marcel (~> 1.0)
-    activesupport (7.2.3)
+    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 (2.8.8)
+      uri (>= 0.13.1)
+    addressable (2.9.0)
       public_suffix (>= 2.0.2, < 8.0)
     base64 (0.3.0)
-    bcrypt (3.1.21)
+    bcrypt (3.1.22)
-    benchmark (0.5.0)
+    bigdecimal (4.1.2)
-    bigdecimal (4.0.1)
     bindex (0.8.1)
     builder (3.3.0)
     byebug (13.0.0)
@@ -93,28 +93,27 @@ GEM
       rack-test (>= 0.6.3)
       regexp_parser (>= 1.5, < 3.0)
       xpath (~> 3.2)
-    cgi (0.5.1)
     concurrent-ruby (1.3.6)
     connection_pool (3.0.2)
     crass (1.0.6)
     date (3.5.1)
-    devise (5.0.2)
+    devise (5.0.3)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
       railties (>= 7.0)
       responders
       warden (~> 1.2.3)
     drb (2.2.3)
-    erb (6.0.2)
+    erb (6.0.4)
     erubi (1.13.1)
-    ffi (1.17.3-aarch64-linux-gnu)
+    ffi (1.17.4-aarch64-linux-gnu)
-    ffi (1.17.3-aarch64-linux-musl)
+    ffi (1.17.4-aarch64-linux-musl)
-    ffi (1.17.3-arm-linux-gnu)
+    ffi (1.17.4-arm-linux-gnu)
-    ffi (1.17.3-arm-linux-musl)
+    ffi (1.17.4-arm-linux-musl)
-    ffi (1.17.3-arm64-darwin)
+    ffi (1.17.4-arm64-darwin)
-    ffi (1.17.3-x86_64-darwin)
+    ffi (1.17.4-x86_64-darwin)
-    ffi (1.17.3-x86_64-linux-gnu)
+    ffi (1.17.4-x86_64-linux-gnu)
-    ffi (1.17.3-x86_64-linux-musl)
+    ffi (1.17.4-x86_64-linux-musl)
     globalid (1.3.0)
       activesupport (>= 6.1)
     i18n (1.14.8)
@@ -124,13 +123,14 @@ GEM
       activesupport (>= 6.0.0)
       railties (>= 6.0.0)
     io-console (0.8.2)
-    irb (1.17.0)
+    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 (2.25.0)
+    loofah (2.25.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
     mail (2.9.0)
@@ -142,10 +142,12 @@ GEM
     marcel (1.1.0)
     matrix (0.4.3)
     mini_mime (1.1.5)
-    minitest (5.27.0)
+    minitest (6.0.6)
+      drb (~> 2.0)
+      prism (~> 1.5)
     mysql2 (0.5.7)
       bigdecimal
-    net-imap (0.6.3)
+    net-imap (0.6.4)
       date
       net-protocol
     net-pop (0.1.2)
@@ -155,21 +157,21 @@ GEM
     net-smtp (0.5.1)
       net-protocol
     nio4r (2.7.5)
-    nokogiri (1.19.1-aarch64-linux-gnu)
+    nokogiri (1.19.3-aarch64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.19.1-aarch64-linux-musl)
+    nokogiri (1.19.3-aarch64-linux-musl)
       racc (~> 1.4)
-    nokogiri (1.19.1-arm-linux-gnu)
+    nokogiri (1.19.3-arm-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.19.1-arm-linux-musl)
+    nokogiri (1.19.3-arm-linux-musl)
       racc (~> 1.4)
-    nokogiri (1.19.1-arm64-darwin)
+    nokogiri (1.19.3-arm64-darwin)
       racc (~> 1.4)
-    nokogiri (1.19.1-x86_64-darwin)
+    nokogiri (1.19.3-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.19.1-x86_64-linux-gnu)
+    nokogiri (1.19.3-x86_64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.19.1-x86_64-linux-musl)
+    nokogiri (1.19.3-x86_64-linux-musl)
       racc (~> 1.4)
     orm_adapter (0.5.0)
     pg (1.6.3)
@@ -186,32 +188,32 @@ GEM
     psych (5.3.1)
       date
       stringio
-    public_suffix (7.0.2)
+    public_suffix (7.0.5)
     puma (6.6.1)
       nio4r (~> 2.0)
     racc (1.8.1)
-    rack (3.2.5)
+    rack (3.2.6)
-    rack-session (2.1.1)
+    rack-session (2.1.2)
       base64 (>= 0.1.0)
       rack (>= 3.0.0)
     rack-test (2.2.0)
       rack (>= 1.3)
     rackup (2.3.1)
       rack (>= 3)
-    rails (7.2.3)
+    rails (8.1.3)
-      actioncable (= 7.2.3)
+      actioncable (= 8.1.3)
-      actionmailbox (= 7.2.3)
+      actionmailbox (= 8.1.3)
-      actionmailer (= 7.2.3)
+      actionmailer (= 8.1.3)
-      actionpack (= 7.2.3)
+      actionpack (= 8.1.3)
-      actiontext (= 7.2.3)
+      actiontext (= 8.1.3)
-      actionview (= 7.2.3)
+      actionview (= 8.1.3)
-      activejob (= 7.2.3)
+      activejob (= 8.1.3)
-      activemodel (= 7.2.3)
+      activemodel (= 8.1.3)
-      activerecord (= 7.2.3)
+      activerecord (= 8.1.3)
-      activestorage (= 7.2.3)
+      activestorage (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
       bundler (>= 1.15.0)
-      railties (= 7.2.3)
+      railties (= 8.1.3)
     rails-dom-testing (2.3.0)
       activesupport (>= 5.0.0)
       minitest
@@ -219,29 +221,28 @@ GEM
     rails-html-sanitizer (1.7.0)
       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 (7.2.3)
+    railties (8.1.3)
-      actionpack (= 7.2.3)
+      actionpack (= 8.1.3)
-      activesupport (= 7.2.3)
+      activesupport (= 8.1.3)
-      cgi
       irb (~> 1.13)
       rackup (>= 1.0.0)
       rake (>= 12.2)
       thor (~> 1.0, >= 1.2.2)
       tsort (>= 0.2)
       zeitwerk (~> 2.6)
-    rake (13.3.1)
+    rake (13.4.2)
     rdoc (7.2.0)
       erb
       psych (>= 4.0.0)
       tsort
-    regexp_parser (2.11.3)
+    regexp_parser (2.12.0)
     reline (0.6.3)
       io-console (~> 0.5)
     responders (3.2.0)
       actionpack (>= 7.0)
       railties (>= 7.0)
     rexml (3.4.4)
-    rubyzip (3.2.2)
+    rubyzip (3.3.0)
     sassc (2.4.0)
       ffi (~> 1.9)
     sassc-rails (2.1.2)
@@ -251,7 +252,7 @@ GEM
       sprockets-rails
       tilt
     securerandom (0.4.1)
-    selenium-webdriver (4.41.0)
+    selenium-webdriver (4.43.0)
       base64 (~> 0.2)
       logger (~> 1.4)
       rexml (~> 3.2, >= 3.2.5)
@@ -265,32 +266,32 @@ GEM
       actionpack (>= 6.1)
       activesupport (>= 6.1)
       sprockets (>= 3.0.0)
-    sqlite3 (2.9.0-aarch64-linux-gnu)
+    sqlite3 (2.9.3-aarch64-linux-gnu)
-    sqlite3 (2.9.0-aarch64-linux-musl)
+    sqlite3 (2.9.3-aarch64-linux-musl)
-    sqlite3 (2.9.0-arm-linux-gnu)
+    sqlite3 (2.9.3-arm-linux-gnu)
-    sqlite3 (2.9.0-arm-linux-musl)
+    sqlite3 (2.9.3-arm-linux-musl)
-    sqlite3 (2.9.0-arm64-darwin)
+    sqlite3 (2.9.3-arm64-darwin)
-    sqlite3 (2.9.0-x86_64-darwin)
+    sqlite3 (2.9.3-x86_64-darwin)
-    sqlite3 (2.9.0-x86_64-linux-gnu)
+    sqlite3 (2.9.3-x86_64-linux-gnu)
-    sqlite3 (2.9.0-x86_64-linux-musl)
+    sqlite3 (2.9.3-x86_64-linux-musl)
     stringio (3.2.0)
     thor (1.5.0)
     tilt (2.7.0)
-    timeout (0.6.0)
+    timeout (0.6.1)
     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 (0.8.0)
       base64
@@ -315,11 +316,10 @@ DEPENDENCIES
   capybara
   devise
   importmap-rails
-  minitest (< 6)
   mysql2 (~> 0.5)
   pg (~> 1.5)
   puma (~> 6.0)
-  rails (~> 7.2.3)
+  rails (~> 8.1.3)
   sassc-rails
   selenium-webdriver
   sprockets-rails

README.md

@@ -89,14 +89,10 @@ 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 +119,10 @@ 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 +135,29 @@ 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 +170,22 @@ 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/stylesheets/application.css

@@ -231,12 +231,17 @@ textarea:invalid {
   text-decoration: underline 1px var(--color-border-gray);
   text-underline-offset: 0.25em;
 }
-[name=cancel],
 .auxiliary {
-  border-color: var(--color-border-gray);
+  border-color: var(--color-nav-gray);
   color: var(--color-nav-gray);
   fill: var(--color-nav-gray);
 }
+table .button {
+  border-color: var(--color-border-gray);
+  font-weight: normal;
+  height: 100%;
+  padding: 0.4em;
+}
 .button:focus-visible,
 .tab:focus-visible,
 .tab:hover {
@@ -259,13 +264,6 @@ textarea:invalid {
   color: var(--color-blue);
   text-decoration-color: var(--color-blue);
 }
-table .button {
-  border-color: var(--color-border-gray);
-  color: var(--color-table-gray);
-  font-weight: normal;
-  height: 100%;
-  padding: 0.4em;
-}
 
 
 /* NOTE: collapse gaps around empty rows (`topside`) once possible with
@@ -360,20 +358,20 @@ header {
   line-height: 2.2em;
   pointer-events: auto;
 }
-.flash:before {
+.flash::before {
-  filter: invert();
+  filter: invert(1);
   height: 1.4em;
   margin: 0 0.5em;
   width: 1.4em;
 }
-.flash.alert:before {
+.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');
 }
 .flash.notice {
@@ -437,15 +435,18 @@ header {
 
 .tabular-form table {
   border: none;
-  border-spacing: 0.4em 0;
+  border-spacing: 0;
-  margin-inline: -0.4em;
 }
 .tabular-form table td {
   border: none;
+  padding-inline-start: 0.4em;
   vertical-align: middle;
 }
-.tabular-form table td {
+.tabular-form table td:first-child {
-  padding-inline: 0;
+  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;

app/controllers/readouts_controller.rb

@@ -6,7 +6,7 @@ class ReadoutsController < ApplicationController
   def new
     @quantities -= @prev_quantities
     # TODO: raise ParameterInvalid if new_quantities.empty?
-    @readouts = current_user.readouts.build(@quantities.map { |q| {quantity: q} })
+    @readouts = @quantities.map { |q| q.readouts.build }
 
     @user_units = current_user.units.ordered
 

app/helpers/application_helper.rb

@@ -208,9 +208,7 @@ 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)
-    # NOTE: Starting from Rails 8.1.0, below condition can be replaced with:
+    if current_page?(options, method: [:get, :post])
-    #   current_page?(options, method: [:get, :post])
-    if request.path == url_for(options)
       html_options = html_options.deep_merge DISABLED_ATTRIBUTES
     end
     link_to name, options, html_options

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

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

@@ -77,16 +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
@@ -114,11 +112,10 @@ class Unit < ApplicationRecord
 
   def successive
     units = Unit.arel_table
-    lead = Arel::Nodes::NamedFunction.new('LAG', [units[:id]])
+    Unit.with(units_with_lag: user.units.ordered.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]]).over.as('lag_id')
-    Unit.with(
+    )).from(Arel::Table.new(:units_with_lag).as(:units))
-      units: user.units.left_outer_joins(:base).select(units[Arel.star], lag_id)
+      .where(units[:lag_id].eq(id)).first
-    ).where(units[:lag_id].eq(id)).first
   end
 end

app/views/measurements/_form.html.erb

@@ -33,7 +33,7 @@
   <div class="flex reverse">
     <%= form.button id: :create_measurement_button, disabled: true -%>
     <%= image_link_to t(:cancel), "close-outline", measurements_path, name: :cancel,
-      class: 'dangerous', onclick: render_turbo_stream('form_close') %>
+      class: 'auxiliary dangerous', onclick: render_turbo_stream('form_close') %>
   </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

@@ -18,18 +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
-    # Allow RAILS_DATABASE_YML to override the database config file path.
-    # Used by `rails test:all_databases` to test against multiple DB adapters.
-    config.paths['config/database'] = [ENV['RAILS_DATABASE_YML']] if ENV['RAILS_DATABASE_YML']
-
     # 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.
     #
@@ -42,16 +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

@@ -24,50 +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
 
-# Multi-database testing — `bundle exec rails test:all_databases`
+# 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
-# Add any number of `test_<name>:` blocks to run the full test suite
+# all of them.
-# against additional database adapters in a single command.
+#test:
-# Each adapter's gem must be available in the bundle:
+#  mysql2:
-#   bundle config --local with "mysql:sqlite"   # mysql + sqlite
+#    <<: *mysql_default
-#   bundle config --local with "mysql:pg"       # mysql + postgresql
+#    adapter: mysql2
-#
+#    database: fixinme_test
-# Example — run tests against MySQL and SQLite:
+#  sqlite3:
-#
+#    <<: *default
-#test_sqlite:
+#    adapter: sqlite3
-#  adapter: sqlite3
+#    database: db/test.sqlite3
-#  database: db/fixinme_test.sqlite3
-#
-# Example — run tests against MySQL and PostgreSQL:
-#
-#test_pg:
-#  adapter: postgresql
-#  database: fixinme_test
-#  username: fixinme
-#  password: Some-password1%
-#  host: localhost

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/devise.rb

@@ -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/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

@@ -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

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.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, 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

@@ -1,19 +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|
-      # Reference :user through :quantity (:measurement may be NULL).
+      t.text :text, null: false
-      t.references :measurement, foreign_key: true
+
-      t.references :quantity, null: false, foreign_key: true
+      t.timestamps
-      # :category + :value + :unit as a separate table? (NumericValue, TextValue)
+    end
-      t.integer :category, null: false, default: 0
+
-      t.float :value, null: false, limit: Float::MANT_DIG
+    create_table :measurements do |t|
-      t.references :unit, foreign_key: true
+      t.datetime :taken_at, null: false
-      # Move to Measurement?
       #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
@@ -47,6 +68,7 @@ ActiveRecord::Schema[7.2].define(version: 2025_01_21_230456) do
     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 "measurements", "notes", on_delete: :nullify
   add_foreign_key "quantities", "quantities", column: "parent_id", on_delete: :cascade
-  add_foreign_key "quantities", "users"
+  add_foreign_key "quantities", "users", on_delete: :cascade
-  add_foreign_key "readouts", "quantities"
+  add_foreign_key "readouts", "measurements", on_delete: :cascade
-  add_foreign_key "readouts", "units"
+  add_foreign_key "readouts", "quantities", column: ["quantity_id", "user_id"], primary_key: ["id", "user_id"]
-  add_foreign_key "readouts", "users"
+  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"
+  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/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.decimal "multiplier", precision: 30, scale: 15, 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/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

lib/tasks/test_databases.rake

@@ -1,118 +0,0 @@
-require 'yaml'
-require 'erb'
-require 'tmpdir'
-
-namespace :test do
-  desc <<~DESC
-    Run the full test suite against every test database configured in database.yml.
-
-    Any top-level key that starts with "test" and contains a Hash is treated as a
-    test database configuration:
-
-      test:           # always required — the primary test database
-        adapter: mysql2
-        database: fixinme_test
-        ...
-
-      test_sqlite:    # optional additional databases
-        adapter: sqlite3
-        database: db/fixinme_test.sqlite3
-
-      test_pg:
-        adapter: postgresql
-        database: fixinme_test
-        ...
-
-    For each database the task will:
-      1. Check that the required adapter gem is available (skip with warning if not).
-      2. Run `rails db:test:prepare` to create/migrate the database.
-      3. Run `rails test` and record pass/fail.
-
-    A summary is printed at the end. The task exits non-zero if any database fails.
-  DESC
-  task :all_databases do
-    db_file    = Rails.root.join('config', 'database.yml')
-    all        = YAML.safe_load(ERB.new(db_file.read).result, aliases: true) || {}
-    test_cfgs  = all.select { |k, v| k.to_s.start_with?('test') && v.is_a?(Hash) }
-    non_test   = all.reject { |k, _| k.to_s.start_with?('test') }
-
-    abort "No test database configurations found in #{db_file}." if test_cfgs.empty?
-
-    results = {}
-
-    test_cfgs.each do |name, config|
-      adapter = config['adapter'].to_s
-
-      puts "\n#{'─' * 64}"
-      puts "  #{name}  (adapter: #{adapter})"
-      puts '─' * 64
-
-      unless adapter_available?(adapter)
-        puts "  SKIPPED — gem for '#{adapter}' adapter not available in bundle."
-        puts "  Add it to Gemfile (e.g. `bundle config --local with #{adapter_group(adapter)}`)"
-        results[name] = :skipped
-        next
-      end
-
-      Dir.mktmpdir('rails_test_db_') do |tmpdir|
-        tmp_yml = File.join(tmpdir, 'database.yml')
-        # Write a standalone database.yml with just this config as `test:`
-        # (non-test configs are preserved so boot doesn't fail on `production:` lookup)
-        File.write(tmp_yml, non_test.merge('test' => config).to_yaml)
-
-        env = { 'RAILS_DATABASE_YML' => tmp_yml }
-
-        if system(env, 'bundle exec rails db:test:prepare')
-          results[name] = system(env, 'bundle exec rails test') ? :pass : :fail
-        else
-          results[name] = :prepare_failed
-        end
-      end
-    end
-
-    puts "\n#{'═' * 64}"
-    puts "  SUMMARY"
-    puts '═' * 64
-    results.each do |name, status|
-      adapter = test_cfgs[name]['adapter']
-      icon    = { pass: '✓', fail: '✗', prepare_failed: '✗', skipped: '–' }[status]
-      label   = { pass: 'PASS', fail: 'FAIL',
-                  prepare_failed: 'PREPARE FAILED', skipped: 'SKIPPED' }[status]
-      puts "  #{icon}  #{name.ljust(26)} (#{adapter.ljust(12)})  #{label}"
-    end
-    puts '═' * 64
-
-    failed = results.count { |_, s| s == :fail || s == :prepare_failed }
-    abort "\n  #{failed} database(s) failed." if failed > 0
-  end
-end
-
-private
-
-# Returns true if the gem required for this adapter is loadable.
-ADAPTER_GEMS = {
-  'mysql2'     => 'mysql2',
-  'sqlite3'    => 'sqlite3',
-  'postgresql' => 'pg',
-  'pg'         => 'pg',
-}.freeze
-
-def adapter_available?(adapter)
-  gem_name = ADAPTER_GEMS.fetch(adapter, adapter)
-  require gem_name
-  true
-rescue LoadError
-  false
-end
-
-# Returns the Bundler group name that installs the adapter gem.
-ADAPTER_GROUPS = {
-  'mysql2'     => 'mysql',
-  'sqlite3'    => 'sqlite',
-  'postgresql' => 'postgresql',
-  'pg'         => 'postgresql',
-}.freeze
-
-def adapter_group(adapter)
-  ADAPTER_GROUPS.fetch(adapter, adapter)
-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

@@ -25,9 +25,10 @@ class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
     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
@@ -38,6 +39,32 @@ class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
   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)
   #  assert_raises(Selenium::WebDriver::Error::StaleElementReferenceError) { element.tag_name }
   #end

test/controllers/measurements_controller_test.rb

@@ -1,8 +0,0 @@
-require "test_helper"
-
-class MeasurementsControllerTest < ActionDispatch::IntegrationTest
-  #test "should get index" do
-  #  get measurements_index_url
-  #  assert_response :success
-  #end
-end

test/controllers/quantities_controller_test.rb

@@ -1,7 +0,0 @@
-require "test_helper"
-
-class QuantitiesControllerTest < ActionDispatch::IntegrationTest
-  # test "the truth" do
-  #   assert true
-  # end
-end

test/controllers/units_controller_test.rb

@@ -1,7 +0,0 @@
-require "test_helper"
-
-class UnitsControllerTest < ActionDispatch::IntegrationTest
-  # test "the truth" do
-  #   assert true
-  # end
-end

test/controllers/users_controller_test.rb

@@ -1,5 +1,7 @@
 require "test_helper"
 
+# TODO: make sure tested actions are covered by system tests and remove all
+# controller tests.
 class UsersControllerTest < ActionDispatch::IntegrationTest
   setup do
     @user = users(:one)

test/models/user_test.rb

@@ -1,7 +0,0 @@
-require "test_helper"
-
-class UserTest < ActiveSupport::TestCase
-  # test "the truth" do
-  #   assert true
-  # end
-end

test/system/tasks_test.rb

@@ -0,0 +1,20 @@
+require 'application_system_test_case'
+
+Rails.application.load_tasks
+# NOTE: for some reason task for checking pending migrations messes up
+# transaction when run during test. It causes all DB changes made before its
+# execution to be rolled back.
+# Run it before tests, so any rake task dependent on it will see it as
+# #already_invoked and won't run it during test. It is redundant anyway, as
+# migrations are run before starting test suite.
+Rake::Task['db:abort_if_pending_migrations'].invoke
+
+class TasksTest < ApplicationSystemTestCase
+  test "db:seed creates admin account" do
+    User.admin.delete_all
+    assert_output /Creating admin account/ do
+      Rake::Task['db:seed'].execute
+    end
+    assert User.admin.exists?
+  end
+end

test/system/units_test.rb

@@ -44,10 +44,12 @@ class UnitsTest < ApplicationSystemTestCase
     within 'tbody > tr:has(input[type=text], textarea)' do
       assert_selector ':focus'
 
-      maxlength = all(:fillable_field).to_h { |f| [f[:name], f[:maxlength].to_i || 2**16] }
+      maxlength = all(:fillable_field).to_h do |field|
+        [field[:name], field[:maxlength].to_i || 2**16]
+      end
       values = {
-        symbol: random_string(rand([1..3, 4..maxlength['unit[symbol]']].sample),
+        symbol: random_string(deep_rand(1..3, 4..maxlength['unit[symbol]']),
-                              except: units.map(&:symbol)),
+                              except: units.map(&:symbol), allow_blank: false),
         description: random_string(rand(0..maxlength['unit[description]']))
       }.with_indifferent_access
       within :field, 'unit[multiplier]' do |field|
@@ -61,7 +63,8 @@ class UnitsTest < ApplicationSystemTestCase
       end
     end
 
-    assert_selector '.flash.notice', text: t('units.create.success', unit: Unit.last.symbol)
+    assert_selector '.flash.notice',
+      text: t('units.create.success', unit: Unit.last.symbol)
     within 'tbody' do
       assert_no_selector :fillable_field
       assert_selector 'tr', count: @user.units.count

test/system/users_test.rb

@@ -204,6 +204,7 @@ class UsersTest < ApplicationSystemTestCase
 
   test 'update profile' do
     # TODO
+    assert true
   end
 
   test 'update status' do
@@ -227,7 +228,8 @@ class UsersTest < ApplicationSystemTestCase
 
     within all(:xpath, "//tbody//tr[not(descendant::select)]").sample do |tr|
       user = User.find_by_email!(first(:link).text)
-      inject_button_to first('td:not(.link)'), "update status", user_path(user), method: :patch,
+      inject_button_to find('td', exact_text: user.status), "update status",
+        user_path(user), method: :patch,
         params: {user: {status: User.statuses.keys.sample}}, data: {turbo: false}
       click_on "update status"
     end
@@ -237,8 +239,8 @@ class UsersTest < ApplicationSystemTestCase
   test 'update status forbidden for non admin' do
     sign_in user: users.reject(&:admin?).select(&:confirmed?).sample
     visit units_path
-    inject_button_to find('body'), "update status", user_path(User.all.sample), method: :patch,
+    inject_button_to find('body'), "update status", user_path(User.all.sample),
-      params: {user: {status: User.statuses.keys.sample}}
+      method: :patch, params: {user: {status: User.statuses.keys.sample}}
     click_on "update status"
     assert_text t('actioncontroller.exceptions.status.forbidden')
   end

test/test_helper.rb

@@ -13,27 +13,36 @@ class ActiveSupport::TestCase
   include ActionView::Helpers::TranslationHelper
 
   # List of categorized Unicode characters:
-  # * http://www.unicode.org/Public/UNIDATA/UnicodeData.txt
+  #   * source: http://www.unicode.org/Public/UNIDATA/UnicodeData.txt
-  # File format: http://www.unicode.org/L2/L1999/UnicodeData.html
+  #   * file format: http://www.unicode.org/L2/L1999/UnicodeData.html
-  # Select from graphic ranges: L, M, N, P, S, Zs
+  #   * select from graphic ranges: L, M, N, P, S, Zs
-  UNICODE_CHARS = {
+  UNICODE_CHARS = [
-    1 => [*"\u0020".."\u007E"],
+    *"\u0020".."\u007E",
-    2 => [*"\u00A0".."\u00AC",
+    *"\u00A0".."\u00AC",
-          *"\u00AE".."\u05FF",
+    *"\u00AE".."\u05FF",
-          *"\u0606".."\u061B",
+    *"\u0606".."\u061B",
-          *"\u061D".."\u06DC",
+    *"\u061D".."\u06DC",
-          *"\u06DE".."\u070E",
+    *"\u06DE".."\u070E",
-          *"\u0710".."\u07FF"]
+    *"\u0710".."\u07FF"
-  }
+  ]
-  UNICODE_CHARS.default = UNICODE_CHARS[1] + UNICODE_CHARS[2]
+  def random_string(length, except: [], allow_blank: true)
-  def random_string(bytes = 10, except: [])
     begin
-      result = ''
+      result = UNICODE_CHARS.sample(length).join
-      result += UNICODE_CHARS[bytes - result.bytesize].sample while bytes > result.bytesize
+    end while except.include?(result) || (!allow_blank && result.blank?)
-    end while except.include?(result)
     result
   end
 
+  def deep_rand(*args)
+    case args
+    when Array
+      args = args.sample
+    when Range
+      args = rand(args)
+    else
+      return args
+    end while true
+  end
+
   # Assumes: max >= step and step = 1e[-]N, both as strings
   def random_number(max, step)
     max.delete!('.')