fix(release): make just release idempotent for re-runs (#948)

RELEASING.md

@@ -18,11 +18,13 @@ just release 1.0.0
 
 This creates a `version-bump/<version>` PR that bumps all version manifests, regenerates lockfiles, and appends a changelog entry. Merge the PR to trigger the build automatically.
 
+Re-running `just release` with the same version is safe — it detects the existing branch and PR, resets to current `main`, regenerates the changelog with any new commits, and updates the PR in place.
+
 ---
 
 ## How It Works
 
-1. **`just release`** runs locally on `main` — computes the next version, creates a `version-bump/<version>` branch, bumps versions in all manifests, regenerates lockfiles, generates a changelog entry, commits, pushes, and opens a PR.
+1. **`just release`** runs locally on `main` — computes the next version, creates (or reuses) a `version-bump/<version>` branch, bumps versions in all manifests, regenerates lockfiles, generates a changelog entry, commits, pushes, and opens (or updates) a PR.
 
 2. **Merge the PR** — the `auto-tag-on-release-pr-merge` workflow detects the `version-bump/*` branch merge and pushes a `v<version>` tag.
 
@@ -120,6 +122,9 @@ Switch to `main` and pull latest before running `just release`.
 ### `just release` fails with "working tree is dirty"
 Commit or stash your changes before running `just release`.
 
+### New commits merged after creating the release PR
+Re-run `just release` from an up-to-date `main`. It resets the branch to current `main`, regenerates the changelog and PR body to include the new commits, and force-pushes the updated branch.
+
 ### Build fails at "Validate version"
 The version string must be valid semver: `MAJOR.MINOR.PATCH` with an optional pre-release suffix. Do not include a `v` prefix.
 

justfile

@@ -445,7 +445,7 @@ bump-version version:
     (unset GIT_DIR GIT_WORK_TREE; cd mobile && flutter pub get)
     echo "Bumped all manifests to {{ version }} and regenerated lockfiles"
 
-# Create a release PR that bumps version and generates changelog
+# Create or update a release PR that bumps version and generates changelog
 release *ARGS:
     #!/usr/bin/env bash
     set -euo pipefail
@@ -479,9 +479,19 @@ release *ARGS:
         echo "Error: working tree is dirty. Commit or stash changes first."
         exit 1
     fi
-    # Create version-bump branch
+    # Switch to version-bump branch (create if needed, reset to main if it exists)
     BRANCH="version-bump/${VERSION}"
+    if git rev-parse --verify "refs/heads/$BRANCH" >/dev/null 2>&1; then
+        echo "Branch '$BRANCH' already exists — resetting to origin/main..."
+        git switch "$BRANCH"
+        git reset --hard origin/main
+    elif git ls-remote --exit-code --heads origin "$BRANCH" >/dev/null 2>&1; then
+        echo "Branch '$BRANCH' exists on remote — checking out and resetting to origin/main..."
+        git switch -c "$BRANCH" --track "origin/$BRANCH"
+        git reset --hard origin/main
+    else
         git switch -c "$BRANCH"
+    fi
     # Bump versions and lockfiles
     just bump-version "$VERSION"
     # Generate changelog
@@ -513,9 +523,14 @@ release *ARGS:
       mobile/pubspec.lock \
       pnpm-lock.yaml \
       CHANGELOG.md
-    git commit -m "chore(release): release version ${VERSION}"
+    RELEASE_MSG="chore(release): release version ${VERSION}"
+    if [[ "$(git log -1 --format='%s' 2>/dev/null)" == "$RELEASE_MSG" ]]; then
+        git commit --amend --no-edit
+    else
+        git commit -m "$RELEASE_MSG"
+    fi
     # Push and open PR
-    git push -u origin "$BRANCH"
+    git push --force-with-lease -u origin "$BRANCH"
     # Build PR body
     PR_BODY="## Release v${VERSION}"$'\n\n'
     if [[ -n "$LAST_TAG" ]]; then
@@ -525,11 +540,21 @@ release *ARGS:
         PR_BODY+="Initial release."$'\n\n'
     fi
     PR_BODY+="**To release:** merge this PR. The tag and build will happen automatically."
+    EXISTING_PR=$(gh pr list --head "$BRANCH" --json url --jq '.[0].url' 2>/dev/null || true)
+    if [[ -n "$EXISTING_PR" ]]; then
+        gh pr edit "$BRANCH" \
+            --title "chore(release): release version ${VERSION}" \
+            --body "$PR_BODY"
+        PR_URL="$EXISTING_PR"
+        echo ""
+        echo "Updated existing release PR: ${PR_URL}"
+    else
         PR_URL=$(gh pr create \
             --title "chore(release): release version ${VERSION}" \
             --body "$PR_BODY")
         echo ""
         echo "Release PR opened: ${PR_URL}"
+    fi
     echo "Merge it to trigger the release build."
 
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