Symfony Translation Catalog Synchronization

New messages get added to the English catalog only (e.g. validators.en.xlf), usually on the newest branch where a feature lands. This skill discovers every such message missing from the oldest maintained branch and adds it there, in all locales, so it cascades up through the regular merge-up.

Core convention

Translation messages always land on the oldest maintained branch, even when the feature that introduced them only exists on a newer branch. Catalogs are append-only with sequential ids, so the newer branch is a superset of the oldest: the missing messages are exactly the trailing entries whose id is greater than the oldest branch's current maximum. Adding them on the oldest branch with the same ids keeps the eventual merge-up conflict-free.

Progress checklist

• Step 1: Get maintained branches and fetch them
• Step 2: Create the branch off the oldest maintained branch
• Step 3: Discover the missing messages per catalog
• Step 4: Add each missing message to every locale
• Step 5: Verify
• Step 6: Commit per component (do not push)

Step 1 — Get maintained branches and fetch them

Use the same endpoint as the symfony-merge-up skill:

curl -s https://symfony.com/releases.json

Read maintained_versions, already sorted oldest → newest (e.g. ["6.4", "7.4", "8.0", "8.1"]). The first is the TARGET (oldest); the rest are the NEWER branches. Fetch all of them from upstream:

for b in <all maintained versions>; do git fetch upstream "$b"; done

Step 2 — Create the branch off the oldest maintained branch

Branch off the upstream ref, never a local branch. Suffix the branch name with the current date (date +%Y-%m-%d) so it stays unique across runs:

git checkout -b "sync-translations-$(date +%Y-%m-%d)" upstream/<TARGET>

Step 3 — Discover the missing messages per catalog

The English catalogs to compare (one per component that ships translations):

git ls-tree -r --name-only upstream/<TARGET> | grep -E 'Resources/translations/.*\.en\.xlf$'

(Today: Validator/.../validators.en.xlf, Form/.../validators.en.xlf, Security/Core/.../security.en.xlf. A NEWER branch may also introduce a brand-new catalog file absent from the TARGET; pick those up by listing catalogs on the newest branch too.)

Helper to extract id<TAB>source pairs from a catalog at any ref:

extract() { # $1 = git ref, $2 = path
  git show "$1:$2" 2>/dev/null | php -r '
$c = stream_get_contents(STDIN);
preg_match_all("#<trans-unit id=\"(\d+)\">\s*<source>(.*?)</source>#s", $c, $m, PREG_SET_ORDER);
foreach ($m as $x) { echo $x[1]."\t".$x[2]."\n"; }'
}

For each catalog file, go over every NEWER branch (oldest → newest) and collect trans-units whose id is greater than the TARGET's current maximum id for that file:

TARGET_MAX=$(extract upstream/<TARGET> "$f" | cut -f1 | sort -n | tail -1)
extract upstream/<NEWER> "$f" | awk -F'\t' -v max="$TARGET_MAX" '$1 > max'

Union the results across NEWER branches and dedup by id (newer branches are cumulative, so the newest usually already contains the full set). Cross-check: every collected source must be absent from the TARGET catalog. If a source already exists in the TARGET under a different id, the catalogs have diverged or been renumbered: stop and ask the user.

Report the discovered messages (component, id, English source) before editing.

Step 4 — Add each missing message to every locale

For each missing message, write a JSON file mapping every non-en locale of the catalog to its translated target, then run the bundled script. Translate the source yourself (a real translation per locale, never the English fallback); the script adds the state="needs-review-translation" flag that marks them for native-speaker review.

# translations.json: {"af": "...", "ar": "...", ..., "zh_TW": "..."}
php scripts/add_message.php \
  --dir src/Symfony/Component/Validator/Resources/translations \
  --id 146 \
  --source "This value is not a valid cron expression." \
  --translations translations.json

The script inserts the <trans-unit> before </body> in every *.xlf of the directory: the English catalog gets the source as its target, every other locale gets its translation. It is idempotent (a locale already holding the id is skipped) and exits non-zero if the JSON doesn't cover exactly the catalog's non-en locales. Pass --source already XML-ready (escape &, <, > if present) so it is reused byte-for-byte. Run it once per catalog and per missing id.

Resulting entries look like:

            <trans-unit id="146">
                <source>This value is not a valid cron expression.</source>
                <target>This value is not a valid cron expression.</target>
            </trans-unit>

            <trans-unit id="146">
                <source>This value is not a valid cron expression.</source>
                <target state="needs-review-translation">Cette valeur n'est pas une expression cron valide.</target>
            </trans-unit>

Step 5 — Verify

Well-formedness of every catalog touched:

for f in <catalog dir>/*.xlf; do xmllint --noout "$f" || echo "BAD: $f"; done

Catalog consistency (same ids/sources across all locales). Run only the TranslationFilesTest of the components you actually touched, e.g. for Validator:

./phpunit src/Symfony/Component/Validator/Tests/Resources/TranslationFilesTest.php

Each touched component has its own test under src/Symfony/Component/<Name>/Tests/Resources/TranslationFilesTest.php (Validator, Form, Security/Core). All must be clean. An unrelated PHPUnit-config schema warning is fine; a test failure is not.

Step 6 — Commit per component (do not push)

One atomic commit per affected component, staging only that component's translation directory:

git add src/Symfony/Component/Validator/Resources/translations/
git commit -m "[Validator] Add translated messages for the <Feature> constraint"

Name the commit after the feature when the new messages map to one (e.g. the Cron constraint); otherwise describe the synchronization. Then stop: never push or open the PR, hand control back to the user.

Gotchas

• The feature (constraint, attribute) introducing a message may not exist on the oldest branch at all. That is expected: only the catalog message goes there, never the feature code.
• Every locale gets the entry, not just *.en.xlf, otherwise TranslationFilesTest fails on a missing id.
• Reuse the id and byte-for-byte English <source> from the NEWER branch, including placeholders like {{ size }}; a different id or altered source breaks the conflict-free merge-up and the consistency test.
• A catalog may legitimately have no missing messages; skip it silently.
• Handle each catalog (Validator, Form, Security/Core) independently, with its own commit and [Component] prefix.