fix: also re-translate merged files when upstream source is updated later

Author: sunnylqm

scripts/sync-translations.sh

@@ -1,15 +1,17 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
-# Print candidate cndocs files that likely need translation sync
-# Strategy:
-# 1) Compare upstream/main vs local production for docs/*.md
-# 2) Map changed docs/<name>.md -> cndocs/<name>.md when target exists
-# 3) Output unique, sorted cndocs paths (one per line)
+# Print candidate cndocs files that need translation sync.
+# Two strategies combined:
+#   A) Compare upstream/main vs local production for docs/*.md (new upstream changes)
+#   B) For previously-merged translations, check if upstream file was updated
+#      more recently than the cndocs translation — if so, re-translate.
 
 REPO_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
 cd "$REPO_ROOT"
 
+PROGRESS_FILE="$REPO_ROOT/scripts/translate-progress.json"
+
 # Ensure upstream exists
 if ! git remote get-url upstream >/dev/null 2>&1; then
   echo "ERROR: missing upstream remote" >&2
@@ -18,18 +20,51 @@ fi
 
 git fetch upstream --quiet
 
-# Changed docs files between production and upstream/main
-changed_docs=$(git diff --name-only production..upstream/main -- 'docs/*.md' || true)
+candidates=()
 
-if [ -z "${changed_docs}" ]; then
-  exit 0
+# --- Strategy A: new upstream changes not yet in production ---
+changed_docs=$(git diff --name-only production..upstream/main -- 'docs/*.md' || true)
+if [ -n "${changed_docs}" ]; then
+  while IFS= read -r f; do
+    [ -z "$f" ] && continue
+    name="${f#docs/}"
+    target="cndocs/${name}"
+    if [ -f "$target" ]; then
+      candidates+=("$target")
+    fi
+  done <<< "$changed_docs"
 fi
 
-while IFS= read -r f; do
-  [ -z "$f" ] && continue
-  name="${f#docs/}"
-  target="cndocs/${name}"
-  if [ -f "$target" ]; then
-    echo "$target"
+# --- Strategy B: merged translations whose upstream source is now newer ---
+if [ -f "$PROGRESS_FILE" ]; then
+  merged_files=$(python3 -c "
+import json, sys
+with open('$PROGRESS_FILE') as f:
+    data = json.load(f)
+for item in data.get('merged', []):
+    print(item)
+" 2>/dev/null || true)
+
+  if [ -n "$merged_files" ]; then
+    while IFS= read -r target; do
+      [ -z "$target" ] && continue
+      # cndocs/foo.md -> docs/foo.md
+      name="${target#cndocs/}"
+      source="docs/${name}"
+
+      # Get upstream last-modified epoch for the source file
+      upstream_epoch=$(git log -1 --format="%ct" upstream/main -- "$source" 2>/dev/null || echo 0)
+      # Get production last-modified epoch for the translated file
+      translation_epoch=$(git log -1 --format="%ct" production -- "$target" 2>/dev/null || echo 0)
+
+      if [ "$upstream_epoch" -gt "$translation_epoch" ] 2>/dev/null; then
+        candidates+=("$target")
+      fi
+    done <<< "$merged_files"
   fi
-done <<< "$changed_docs" | sort -u
+fi
+
+# Deduplicate and sort
+if [ ${#candidates[@]} -gt 0 ]; then
+  printf '%s\n' "${candidates[@]}" | sort -u
+fi