Add multi-database test runner (test:all_databases)

Adds `bundle exec rails test:all_databases` which runs the full test
suite against every test database configured in database.yml in a single
command.

Convention: any top-level key starting with "test" that contains a Hash
is a test database. `test:` is the required primary; `test_<name>:` blocks
are optional additional adapters (e.g. test_sqlite, test_pg).

For each configured database the task:
  1. Checks the required adapter gem is available (skips with warning if not)
  2. Runs `rails db:test:prepare` to create and migrate the database
  3. Runs `rails test` and records pass/fail
  4. Prints a summary and exits non-zero if any database failed

Mechanism: a RAILS_DATABASE_YML env var points each subprocess to a
temporary database.yml that contains only the current test config.
config/application.rb(.dist) reads this var and overrides Rails'
database config path before initialisation, so no monkey-patching of
the test runner is required.

config/database.yml.dist is updated with documented examples for SQLite
and PostgreSQL additional test databases.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/assets/stylesheets/application.css

@@ -18,14 +18,12 @@
 /* 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>; <a> as link/button),
+ * 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. */
-/* TODO: review styles with multiple selectors and try to convert them to the same
- * specificity. */
 :root {
   --color-focus-gray: #f3f3f3;
   --color-border-gray: #dddddd;
@@ -57,8 +55,8 @@
 :focus-visible {
   outline: none;
 }
-/* NOTE: move to higher priority layer instead of using !important? */
-/* TODO: add CSS @layer requirements in README */
+/* NOTE: move to higher priority layer instead of using !important?; add CSS
+ * @layer requirements in README */
 [disabled] {
   border-color: var(--color-border-gray) !important;
   color: var(--color-border-gray) !important;
@@ -80,10 +78,13 @@
  *  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;
@@ -101,7 +102,14 @@ textarea {
   border-radius: 0.25em;
   padding: 0.2em 0.4em;
 }
-svg,
+svg {
+  height: 1.4em;
+  margin: 0 0.2em 0 0;
+  width: 1.4em;
+}
+svg:last-child {
+  margin-right: 0;
+}
 textarea {
   margin: 0;
 }
@@ -153,6 +161,10 @@ 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,
@@ -214,21 +226,17 @@ textarea:invalid {
   padding: 0.6em 0.5em;
   width: fit-content;
 }
+.link {
+  color: inherit;
+  text-decoration: underline 1px var(--color-border-gray);
+  text-underline-offset: 0.25em;
+}
 [name=cancel],
 .auxiliary {
   border-color: var(--color-border-gray);
   color: var(--color-nav-gray);
   fill: var(--color-nav-gray);
 }
-.button > svg,
-.tab > svg {
-  height: 1.4em;
-  width: 1.4em;
-}
-.button > svg:not(:last-child),
-.tab > svg:not(:last-child) {
-  margin-right: 0.2em;
-}
 .button:focus-visible,
 .tab:focus-visible,
 .tab:hover {
@@ -244,6 +252,13 @@ textarea:invalid {
   background-color: var(--color-red);
   border-color: var(--color-red);
 }
+.link:focus-visible {
+  text-decoration-color: var(--color-gray);
+}
+.link:hover {
+  color: var(--color-blue);
+  text-decoration-color: var(--color-blue);
+}
 table .button {
   border-color: var(--color-border-gray);
   color: var(--color-table-gray);
@@ -251,15 +266,6 @@ table .button {
   height: 100%;
   padding: 0.4em;
 }
-/* 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. */
-/* TODO: apply link class to non-button/-tab links. Add light underscore for links? */
-input[type=text]:read-only,
-textarea:read-only {
-  border: none;
-  padding-inline: 0;
-}
 
 
 /* NOTE: collapse gaps around empty rows (`topside`) once possible with
@@ -271,16 +277,16 @@ body {
   grid-template-areas:
     "header    header  header"
     "nav       nav     nav"
-    "leftside  topside rightside"
     "leftside  main    rightside";
   grid-template-columns: 1fr minmax(max-content, 2fr) 1fr;
   font-family: system-ui;
   margin: 0.4em;
 }
-body:not(:has(.topside-area)) {
+body:has(> .topside-area) {
   grid-template-areas:
     "header    header  header"
     "nav       nav     nav"
+    "leftside  topside rightside"
     "leftside  main    rightside";
 }
 
@@ -431,14 +437,18 @@ header {
 
 .tabular-form table {
   border: none;
+  border-spacing: 0.4em 0;
+  margin-inline: -0.4em;
 }
 .tabular-form table td {
   border: none;
-  text-align: left;
   vertical-align: middle;
 }
-.tabular-form table td:first-child {
-  color: inherit;
+.tabular-form table td {
+  padding-inline: 0;
+}
+.tabular-form table :is(form, input, select, textarea):only-child {
+  margin-inline-start: 0;
 }
 
 
@@ -457,59 +467,41 @@ header {
   background-color: var(--color-focus-gray);
 }
 .items-table th {
-  padding-block: 0.75em;
+  padding: 0.75em 0 0.75em 1em;
   text-align: center;
 }
-.items-table th,
-.items-table td {
-  padding-inline: 1em 0;
-}
-/* For <a> to fill <td> completely, we use an `::after` pseudoelement. */
-.items-table td.link {
-  padding: 0;
-  position: relative;
-}
-.items-table td.link a {
-  color: inherit;
-  font: inherit;
-}
-.items-table td.link a::after {
-  content: '';
-  inset: 0;
-  position: absolute;
-}
-.items-table td:first-child {
-  padding-inline-start: calc(1em + var(--depth) * 0.8em);
-}
-.items-table td:has(input, select, textarea) {
-  padding-inline-start: calc(0.6em - 0.9px);
-}
-.items-table td:first-child:has(input, select, textarea) {
-  padding-inline-start: calc(0.6em + var(--depth) * 0.8em - 0.9px);
-}
 .items-table th:last-child {
   padding-inline-end: 0.4em;
 }
-.items-table td:last-child {
-  padding-inline-end: 0.1em;
-}
 .items-table td {
   border-top: 1px solid var(--color-border-gray);
   height: 2.4em;
-  padding-block: 0.1em;
+  padding: 0.1em 0 0.1em calc(1em + var(--depth) * 0.8em);
 }
-.items-table .actions {
-  display: flex;
+.items-table td:last-child {
+  padding-inline-end: 0.1em;
+}
+.items-table :is(form, input, select, textarea):only-child {
+  margin-inline-start: calc(-0.4em - 0.9px);
+}
+/* For <a> to fill table cell completely, we use an `::after` pseudoelement. */
+/* 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;
 }
-.items-table .actions.centered {
-  justify-content: center;
-}
-.items-table tr.dropzone {
+.items-table .dropzone {
   position: relative;
 }
-.items-table tr.dropzone::after {
+.items-table .dropzone::after {
   content: '';
   inset: 1px 0 0 0;
   position: absolute;
@@ -517,72 +509,37 @@ header {
   outline-offset: -1px;
   z-index: var(--z-index-table-row-outline);
 }
-.items-table td.handle {
-  cursor: move;
+.items-table .handle {
+  cursor: grab;
 }
-.items-table tr.form td {
+.items-table .form td {
   vertical-align: top;
 }
-
-/* TODO: replace `:hover:focus-visible` combos with proper LOVE style order. */
-/* TODO: update table styling: simplify selectors, deduplicate, remove non-font rem. */
-.items-table td.link a:hover,
-.items-table td.link a:focus-visible,
-.items-table td.link a:hover:focus-visible {
-  text-decoration: underline;
-  text-decoration-thickness: 0.05rem;
-  text-underline-offset: 0.2rem;
-}
-.items-table td.link a:hover {
-  color: var(--color-blue);
-}
-.items-table td.link a:focus-visible {
-  text-decoration-color: var(--color-gray);
-}
-.items-table td.link a:hover:focus-visible {
-  color: var(--color-dark-blue);
-}
-
 .items-table td:not(:first-child),
 .grayed {
   color: var(--color-table-gray);
-  fill: var(--color-table-gray);
+  fill: var(--color-gray);
 }
-.items-table svg {
-  height: 1rem;
-  vertical-align: middle;
-  width: 1rem;
-}
-.items-table svg:last-child {
-  height: 1.2rem;
-  width: 1.2rem;
-}
-.items-table td.svg {
+.items-table td:has(> svg:only-child) {
   text-align: center;
 }
-.items-table td.number {
-  text-align: right;
-}
 
 
-.centered {
+.center {
   margin: 0 auto;
 }
-.extendedright {
-  margin-right: auto;
-}
 .hexpand {
   width: 100%;
 }
-.hflex {
+.flex {
   display: flex;
   gap: 0.8em;
 }
-.hflex.reverse {
+.flex.reverse {
   flex-direction: row-reverse;
 }
-.hflex.centered {
-  justify-content: center;
+.flex.vertical {
+  flex-direction: column;
 }
 .hint {
   color: var(--color-table-gray);
@@ -597,10 +554,11 @@ header {
   color: var(--color-gray);
   font-style: italic;
 }
-.vflex {
-  display: flex;
-  gap: 0.8em;
-  flex-direction: column;
+.ralign {
+  text-align: right;
+}
+.rextend {
+  margin-right: auto;
 }
 
 
@@ -647,7 +605,7 @@ summary::marker {
 }
 /* NOTE: use `details[open]::details-content` once widely available. */
 details[open] ul {
-  background: white;
+  background-color: white;
   border: 1px solid var(--color-border-gray);
   border-radius: 0.25em;
   box-shadow: 1px 1px 3px var(--color-border-gray);
@@ -670,11 +628,6 @@ li input[type=checkbox] {
 li::marker {
   content: '';
 }
-
-#measurement_form {
-  min-width: 66%;
-  width: max-content;
-}
 /*
  * TODO:
  * * disable <label> containing disabled checkbox: `label:has(input[disabled])`,
@@ -682,3 +635,8 @@ li::marker {
  * * focused label styling (currently only checkbox has focus),
  * * disabled checkbox blue square focus removal.
  * */
+
+#measurement_form {
+  min-width: 66%;
+  width: max-content;
+}

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/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) %>

app/views/measurements/_form.html.erb

@@ -1,13 +1,13 @@
 <%= tabular_form_with model: Measurement.new, id: :measurement_form,
-  class: 'topside-area vflex centered',
+  class: 'topside-area flex vertical center',
   html: {onkeydown: 'formProcessKey(event)'} do |form| %>
 
-  <table class="items-table centered">
+  <table class="items-table center">
     <tbody id="readouts">
       <%= tabular_fields_for @measurement do |form| %>
         <tr class="italic">
           <td class="hexpand hmin50"><%= t '.taken_at_html' %></td>
-          <td colspan="3" class="number">
+          <td colspan="3" class="ralign">
             <%= form.datetime_field :taken_at, required: true %>
           </td>
         </tr>
@@ -16,7 +16,7 @@
   </table>
 
   <%# TODO: right-click selection; unnecessary with hierarchical tags? %>
-  <details id="quantity_select" class="centered hexpand" open
+  <details id="quantity_select" class="center hexpand" open
            onkeydown="detailsProcessKey(event)">
     <summary autofocus>
       <!-- TODO: Set content with CSS when span empty to avoid duplication -->
@@ -30,7 +30,7 @@
     <ul><%= quantities_check_boxes(@quantities) %></ul>
   </details>
 
-  <div class="hflex reverse">
+  <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') %>

app/views/quantities/_form.html.erb

@@ -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 %>">
-    <%= link_to quantity, edit_quantity_path(quantity), onclick: 'this.blur();',
-      data: {turbo_stream: true} %>
+  <td style="--depth:<%= quantity.depth %>">
+    <%= link_to quantity, edit_quantity_path(quantity), class: 'link',
+      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

@@ -15,7 +15,7 @@
   <thead>
     <tr>
       <th><%= Quantity.human_attribute_name(:name) %></th>
-      <th><%= Quantity.human_attribute_name(:description) %></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

@@ -4,17 +4,17 @@
     <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.hidden_field :quantity_id %>
       <%= 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="actions">
+    <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),

app/views/units/_form.html.erb

@@ -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? %>
     </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 %>">
-    <%= link_to unit, edit_unit_path(unit), onclick: 'this.blur();', data: {turbo_stream: true} %>
+  <td style="--depth:<%= unit.base_id? ? 1 : 0 %>">
+    <%= 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 %></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

@@ -14,7 +14,7 @@
   <thead>
     <tr>
       <th><%= Unit.human_attribute_name(:symbol) %></th>
-      <th><%= Unit.human_attribute_name(:description) %></th>
+      <th class="hexpand"><%= Unit.human_attribute_name(:description) %></th>
       <th><%= Unit.human_attribute_name(:multiplier) %></th>
       <% if current_user.at_least(:active) %>
         <th><%= t :actions %></th>

app/views/users/index.html.erb

@@ -11,7 +11,7 @@
   <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 %>
@@ -22,11 +22,11 @@
             <% end %>
           <% end %>
         </td>
-        <td class="svg">
+        <td>
           <%= svg_tag 'pictograms/checkbox-marked-outline' if user.confirmed_at.present? %>
         </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) %>
           <% 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 %>

config/application.rb.dist

@@ -20,6 +20,10 @@ Bundler.require(*Rails.groups)
 
 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/database.yml.dist

@@ -48,3 +48,26 @@ production:
 #test:
 #  <<: *default
 #  database: fixinme_test
+
+# Multi-database testing — `bundle exec rails test:all_databases`
+# ---------------------------------------------------------------
+# Add any number of `test_<name>:` blocks to run the full test suite
+# against additional database adapters in a single command.
+# Each adapter's gem must be available in the bundle:
+#   bundle config --local with "mysql:sqlite"   # mysql + sqlite
+#   bundle config --local with "mysql:pg"       # mysql + postgresql
+#
+# Example — run tests against MySQL and SQLite:
+#
+#test_sqlite:
+#  adapter: 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

lib/tasks/test_databases.rake

@@ -0,0 +1,118 @@
+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

test/system/users_test.rb

@@ -229,7 +229,7 @@ class UsersTest < ApplicationSystemTestCase
       user = User.find_by_email!(first(:link).text)
       inject_button_to first('td:not(.link)'), "update status", user_path(user), method: :patch,
         params: {user: {status: User.statuses.keys.sample}}, data: {turbo: false}
-      execute_script("arguments[0].click()", find_button("update status"))
+      click_on "update status"
     end
     assert_title 'The change you wanted was rejected (422)'
   end