Configure test environment (#1282)

Alternative to #1261, lifted from the existing [generator][]. However,
since the authoring of that generator, the structure of
`config/environments/test.rb` has changed, so we no longer need
conditionals.

Additionally, we set `action_dispatch.show_exceptions` to `:none` rather
than comment it out to be explicit about the value.

[generator]: https://github.com/thoughtbot/suspenders/blob/main/lib/generators/suspenders/environments/test_generator.rb

Co-authored-by: Rob Whittaker <rob@thoughtbot.com>
Co-authored-by: Jose Blanco <53355525+laicuRoot@users.noreply.github.com>

Author: 3 people

FEATURES.md

@@ -29,7 +29,7 @@ The following environment variables are available in `production`:
 ### Test
 
 - Enables [raise_on_missing_translations][].
-- Disables [action_dispatch.show_exceptions][].
+- Sets [action_dispatch.show_exceptions][] to `:none`.
 
 [raise_on_missing_translations]: https://guides.rubyonrails.org/configuring.html#config-i18n-raise-on-missing-translations
 [action_dispatch.show_exceptions]: https://edgeguides.rubyonrails.org/configuring.html#config-action-dispatch-show-exceptions

lib/templates/web.rb

@@ -42,6 +42,7 @@ def install_gems
   configure_inline_svg
 
   # Environments
+  setup_test_environment
   setup_development_environment
   setup_production_environment
   setup_application
@@ -207,6 +208,11 @@ def configure_inline_svg
   RUBY
 end
 
+def setup_test_environment
+  gsub_file "config/environments/test.rb", /config\.action_dispatch\.show_exceptions = :rescuable/, "config.action_dispatch.show_exceptions = :none"
+  uncomment_lines "config/environments/test.rb", /config\.i18n\.raise_on_missing_translations/
+end
+
 def setup_development_environment
   environment "config.active_model.i18n_customize_full_message = true", env: "development"
   uncomment_lines "config/environments/development.rb", /config\.i18n\.raise_on_missing_translations/
@@ -312,7 +318,7 @@ def update_readme
       ### Test
 
       - Enables [raise_on_missing_translations][].
-      - Disables [action_dispatch.show_exceptions][].
+      - Sets [action_dispatch.show_exceptions][] to `:none`.
 
       [raise_on_missing_translations]: https://guides.rubyonrails.org/configuring.html#config-i18n-raise-on-missing-translations
       [action_dispatch.show_exceptions]: https://edgeguides.rubyonrails.org/configuring.html#config-action-dispatch-show-exceptions