Translating

The desktop app (pdfs-app), the tray (pdfs-tray) and the search prompt (pdfs-prompt) are translated with GNU gettext in the pdfs text domain. The pdfs command-line tool and the daemon's own messages stay in English, because scripts parse their output.

US English is the source language. The shipped catalogs are listed in po/LINGUAS: German, British English, Spanish, French, Italian, Dutch, Polish and Brazilian Portuguese.

Picking a language

The apps follow the system locale (LANGUAGE, LC_ALL, LC_MESSAGES, LANG). Preferences → General → Appearance → Language overrides that for the app, the tray and the prompt. The choice is stored as language in config.json and takes effect the next time they start.

Layout

Path	Purpose
crates/pdfs-gui/src/i18n.rs	Locale setup and the gettext, gettext_f, ngettext_f, pgettext and gettext_noop helpers
po/POTFILES.in	Sources that xgettext scans
po/pdfs.pot	The template, generated from the sources
po/<lang>.po	One catalog per language
po/update.sh	Regenerates the template and merges it into every catalog
po/build.sh <localedir>	Compiles the catalogs to <localedir>/<lang>/LC_MESSAGES/pdfs.mo

Updating an existing translation

1. Run po/update.sh. It regenerates po/pdfs.pot and merges new and changed strings into each catalog, marking changed ones fuzzy.

2. Edit po/<lang>.po with a PO editor (Poedit, Lokalize, GNOME Translation Editor) or a text editor. Translate the empty entries and review every fuzzy one, then remove its fuzzy flag.

3. Check the catalog with msgfmt --check --statistics -o /dev/null po/<lang>.po.

4. Try it from the source tree:

   po/build.sh target/locale
   PDFS_LOCALEDIR=target/locale LANGUAGE=<lang> cargo run -p pdfs-gui --bin pdfs-app

Adding a language

1. Add the code (for example sv or pt_PT) to po/LINGUAS, keeping the list sorted.
2. Run po/update.sh. It creates po/<lang>.po from the template with msginit.
3. Fill in the Plural-Forms header if msginit did not, and translate the catalog.
4. Add the code and the language's own name to LANGUAGES in crates/pdfs-gui/src/i18n.rs, so the Preferences picker offers it.
5. Add GenericName[<lang>], Comment[<lang>] and Keywords[<lang>] lines to the two desktop files in packaging/.

cargo test -p pdfs-gui checks that every language in the picker has a catalog, that po/POTFILES.in lists every source file that calls gettext, and that every catalog passes msgfmt --check.

Rules for translators

• Keep every {placeholder} from the English text. You may move it, but not rename or drop it. msgfmt --check rejects a catalog where they differ. Plural forms keep {n} in every form.

• Read the #. translator comments above an entry. They explain placeholders and date formats.

• Date entries such as %b %e are strftime formats for GLib's DateTime::format. Translate them into the order and separators your language uses, not into literal dates.

• A msgctxt such as verb or column tells you which meaning of a short word is meant.

• Keep product names as they are: Proton Drive, Proton, Google Takeout.

• Use the same term for the same thing across the catalog, and follow the terminology of your desktop (GNOME or KDE) for common actions such as Trash, Preferences and Cancel.

• The English UI uses one term per concept. Pick one translation for each and keep it:

  Concept	English term
  The root of the user's Drive	My files
  The background service	Proton Drive service (never "daemon" or "mount")
  A folder with a full copy on this computer	Synced folder
  A folder whose files download when opened	Online-only folder
  A single file kept on this computer	Available offline
  A single file that is not on this computer	Online only
  Where My files appears on disk	Proton Drive folder
  Stop syncing a folder	Stop syncing
  Two versions of one file	Conflict

Rules for developers

• Wrap every user-visible GUI string: gettext("Move to Trash").
• Never build a sentence from translated pieces or with format!. Use named placeholders: gettext_f("Moved {name} to Trash", &[("name", &name)]).
• Counts use ngettext_f("{n} item", "{n} items", count, &[]); {n} is filled in for you.
• Give short, ambiguous words a context: pgettext("verb", "Open").
• Mark labels in const tables with gettext_noop and translate them where they are shown.
• The message id must be a single string literal on one line, since xgettext reads literals only.
• Add a // Translators: comment on the line above a call whose meaning is not obvious.
• Do not translate log messages, CLI output, action or icon names, or values the daemon sends back.
• Run po/update.sh after changing strings and commit the updated template and catalogs.