Add comprehensive locale testing and improve translation coverage

[codeling]

Summary

This change adds comprehensive test coverage for locale files and improves translation coverage throughout the codebase by extracting hardcoded English strings into translatable keys.

Key Changes

New Tests

• tests/Unit/LocaleFilesTest.php: Validates all locale files for correctness

  • Ensures locale files define valid string arrays with no duplicates
  • Verifies UTF-8 encoding and absence of control characters
  • Validates date format strings
  • Checks that placeholder counts match between keys and translations
  • Reports missing translations without failing (allows incomplete translations)
  • Detects unused translation keys in locale files

• tests/Integration/LocaleTest.php: Tests locale functionality in the running application

  • Verifies all main views render successfully with each locale
  • Checks HTML language attribute and charset are set correctly
  • Validates toolbar tooltips, titles, and dates use translations
  • Tests form buttons, list headers, and upload script messages are translated
  • Verifies error messages, upload confirmations, and markdown help examples are translated

• tests/Integration/LocaleEscapingTest.php: Security test for translation escaping

  • Ensures translations with markup and quotes are properly escaped
  • Verifies malicious payloads in translations cannot break out of attributes or inject scripts

Code Improvements

• index.php: Extracted hardcoded strings into translatable keys

  • Markdown syntax examples in the formatting help drawer
  • Error messages for page creation, saving, and git operations
  • Login disabled warning message
  • Similar page suggestion note
  • Upload script messages (JavaScript)

• functions.php: Added __js() function for translating JavaScript string literals

  • Properly escapes translations for use in inline JavaScript
  • Uses JSON encoding with appropriate HTML entity flags

• auth.php: Made IP restriction message translatable (with fallback for api.php)

Locale File Updates

• locales/en.php: Restructured to only contain entries that differ from their keys

  • Added documentation explaining the English locale approach
  • Removed redundant entries where key equals value

• locales/de.php, locales/oc.php, locales/ja.php:

  • Removed unused 'Recent' and 'Exit' entries
  • Changed 'Log Out' to 'Log out' for consistency
  • Added new translations for extracted strings
  • Fixed character restriction message (changed '/' to '..')

Notable Implementation Details

• The __() function returns the key itself if no translation exists, so the English locale only needs entries where the translation differs from the key
• The __js() function uses html_entity_decode() to convert HTML entities back to characters before JSON encoding, ensuring proper JavaScript string literals
• Tests use data providers to run the same test suite against all available locales
• Missing translations are reported as incomplete tests rather than failures, allowing gradual translation coverage

https://claude.ai/code/session_01UnF3JNHe2m9RQM1BRKdBMY