update dep workflow github compare link (#35212)

.github/workflows/update-dep.yml

@@ -40,6 +40,15 @@ jobs:
 
           SED=sed
 
+          get_dep_url() {
+            sed -n '/deps = {/, /^}/p' DEPS | sed 's/deps = //' |
+              python3 -c "import sys, ast; d=ast.literal_eval(sys.stdin.read()); dep=d[\"$1\"]; print(dep) if isinstance(dep, str) else print(dep.get(\"url\"))"
+          }
+
+          get_dep_repo() {
+            echo "$1" | grep -Po '(?<=github.com\/).*?(?=\.git)?(?=@)' | sed 's/\.git//'
+          }
+
           # Inputs
           DEP="${{ inputs.dep }}"
           DEPREF="${{ inputs.ref }}"
@@ -47,12 +56,7 @@ jobs:
           [[ "${DEP:?}" =~ ^[a-zA-Z/-]+$ ]] || { echo "Input dependency validation failed"; exit 1; }
           if [[ -z "${DEPREF}" ]]; then
             echo "Attempting to guess ref hash"
-            DEP_REPO=$(\
-                sed -n '/deps = {/, /^}/p' DEPS|\
-                sed 's/deps = //'|\
-                python3 -c "import sys,ast; d=ast.literal_eval(sys.stdin.read()); dep=d[\""$DEP"\"]; print(dep) if isinstance(dep, str) else print(dep.get(\"url\"))"|\
-                grep -Po '(?<=github.com\/).*?(?=\.git)?(?=@)'|\
-                sed 's/\.git//')
+            DEP_REPO=$(get_dep_repo "$(get_dep_url "$DEP")")
             gh api /repos/"${DEP_REPO}"/commits/master -q .sha > /tmp/DEPREF || gh api /repos/"${DEP_REPO}"/commits/main -q .sha > /tmp/DEPREF
             DEPREF=$(</tmp/DEPREF)
           fi
@@ -68,8 +72,13 @@ jobs:
           for branch in "${branches[@]}"
           do
             git switch "$branch"
+            # Current dep URL on this branch (before bump) — used for compare link in PR body
+            DEP_URL=$(get_dep_url "$DEP")
+            DEP_REPO=$(get_dep_repo "$DEP_URL")
+            OLD_REF="${DEP_URL##*@}"
+
             pr_branch="update-dep-${branch}-${DEP}-${DEPREF}"
-            if git rev-parse --verify "$pr_branch"; then continue; fi # Skip duplicate
+            if git rev-parse --verify "$pr_branch" 2>/dev/null; then continue; fi # Skip duplicate
             git switch -c "$pr_branch"
             "$SED" -i -e "s,^\(\s*\"$DEP\"\s*:\s*\"https.*\)@[^\"]*\",\1@$DEPREF\"," \
                       -e "/^\s*\"${DEP//\//\\/}\"\s*:\s*{/,/@/ s/@[^\"]*/@$DEPREF/" DEPS
@@ -83,5 +92,6 @@ jobs:
                 --field sha="$(git rev-parse "$pr_branch:DEPS")"
             git restore DEPS
             git pull
-            gh pr create --base "${branch}" -f -t "Update dependency ${DEP}@${DEPREF}" -l "CI/run-audit-deps"
+            PR_BODY="https://github.com/${DEP_REPO}/compare/${OLD_REF}...${DEPREF}"
+            gh pr create --base "${branch}" -t "Update dependency ${DEP}@${DEPREF}" -b "${PR_BODY}" -l "CI/run-audit-deps"
           done