doc: update README to test PR squashing

.github/workflows/commit-lint.yml

@@ -9,15 +9,16 @@ jobs:
   lint-commit-message:
     runs-on: ubuntu-latest
     steps:
+      - name: Compute number of commits in the PR
+        id: nb-of-commits
+        run: echo "::set-output name=nb::$((${{ github.event.pull_request.commits }} + 1))"
       - uses: actions/checkout@v2
         with:
-          # Last 100 commits should be enough for a PR
-          fetch-depth: 100
+          fetch-depth: ${{ steps.nb-of-commits.outputs.nb }}
       - name: Install Node.js
         uses: actions/setup-node@v2
         with:
           node-version: ${{ env.NODE_VERSION }}
       - name: Validate commit messages
         run: |
           echo "::add-matcher::.github/workflows/commit-lint-problem-matcher.json"
-          git log --oneline ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }} | grep -v -e fixup -e squash | awk '{ print $1 }' |  xargs npx -q core-validate-commit --no-validate-metadata --tap

.github/workflows/commit-queue.yml

@@ -18,19 +18,13 @@ env:
 
 jobs:
   commitQueue:
-    if: github.repository == 'nodejs/node'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
         with:
           # Needs the whole git history for ncu to work
           # See https://github.com/nodejs/node-core-utils/pull/486
           fetch-depth: 0
-          # A personal token is required because pushing with GITHUB_TOKEN will
-          # prevent commits from running CI after they land. It needs
-          # to be set here because `checkout` configures GitHub authentication
-          # for push as well.
-          token: ${{ secrets.GH_USER_TOKEN }}
 
       # Install dependencies
       - name: Install Node.js
@@ -71,8 +65,8 @@ jobs:
         run: |
           ncu-config set branch ${DEFAULT_BRANCH}
           ncu-config set upstream origin
-          ncu-config set username "${{ secrets.GH_USER_NAME }}"
-          ncu-config set token "${{ secrets.GH_USER_TOKEN }}"
+          ncu-config set username "${{ github.actor }}"
+          ncu-config set token "${{ secrets.GITHUB_TOKEN }}"
           ncu-config set jenkins_token "${{ secrets.JENKINS_TOKEN }}"
           ncu-config set repo "${REPOSITORY}"
           ncu-config set owner "${OWNER}"

README.md

@@ -10,7 +10,7 @@
   </a>
 </p>
 
-Node.js is an open-source, cross-platform, JavaScript runtime environment. It
+Node.js is an amazing project. It
 executes JavaScript code outside of a browser. For more information on using
 Node.js, see the [Node.js Website][].
 

doc/guides/commit-queue.md

@@ -25,7 +25,7 @@ From a high-level, the Commit Queue works as follow:
    2. Check if the last Jenkins CI is finished running (if it is not, skip this
       PR)
    3. Remove the `commit-queue` label
-   4. Run `git node land <pr>`
+   4. Run `git node land <pr> --oneCommitMax`
    5. If it fails:
       1. Abort `git node land` session
       2. Add `commit-queue-failed` label to the PR
@@ -37,6 +37,12 @@ From a high-level, the Commit Queue works as follow:
       3. Close the PR
       4. Go to next PR in the queue
 
+To make the Commit Queue squash all the commits on a pull request in the first
+one, add the `commit-queue-squash` label.
+To make the Commit Queue land a pull request containing several commits, add the
+`commit-queue-rebase` label. When using this option, make sure
+that all commits are self-contained, meaning every commit should pass all tests.
+
 ## Current limitations
 
 The Commit Queue feature is still in early stages, and as such it might not

tools/actions/commit-queue.sh

@@ -18,6 +18,10 @@ issueUrl() {
   echo "$API_URL/repos/${OWNER}/${REPOSITORY}/issues/${1}"
 }
 
+mergeUrl() {
+  echo "$API_URL/repos/${OWNER}/${REPOSITORY}/pulls/${1}/merge"
+}
+
 labelsUrl() {
   echo "$(issueUrl "${1}")/labels"
 }
@@ -70,7 +74,15 @@ for pr in "$@"; do
   # Delete the commit queue label
   gitHubCurl "$(labelsUrl "$pr")"/"$COMMIT_QUEUE_LABEL" DELETE
 
-  git node land --autorebase --yes "$pr" >output 2>&1 || echo "Failed to land #${pr}"
+  if gitHubCurl "$(labelsUrl "$pr")" GET | jq -e 'map(.name) | index("commit-queue-squash")'; then
+    MULTIPLE_COMMIT_POLICY="--fixupAll"
+  elif gitHubCurl "$(labelsUrl "$pr")" GET | jq -e 'map(.name) | index("commit-queue-rebase")'; then
+    MULTIPLE_COMMIT_POLICY=""
+  else
+    MULTIPLE_COMMIT_POLICY="--oneCommitMax"
+  fi
+
+  git node land --autorebase --yes $MULTIPLE_COMMIT_POLICY "$pr" >output 2>&1 || echo "Failed to land #${pr}"
   # cat here otherwise we'll be supressing the output of git node land
   cat output
 
@@ -84,12 +96,25 @@ for pr in "$@"; do
     git node land --abort --yes
     continue
   fi
-
-  commits="$(git rev-parse $UPSTREAM/$DEFAULT_BRANCH)...$(git rev-parse HEAD)"
 
-  if ! git push $UPSTREAM $DEFAULT_BRANCH >> output 2>&1; then
-    commit_queue_failed "$pr"
-    continue
+  if [ -z "$MULTIPLE_COMMIT_POLICY" ]; then
+    commits="$(git rev-parse $UPSTREAM/$DEFAULT_BRANCH)...$(git rev-parse HEAD)"
+
+    if ! git push $UPSTREAM $DEFAULT_BRANCH >> output 2>&1; then
+      commit_queue_failed "$pr"
+      continue
+    fi
+  else
+    # If there's only one commit, we can use the Squash and Merge feature from GitHub
+    gitHubCurl "$(mergeUrl "$pr")" PUT --data "$(\
+      TITLE="$(git log -1 --pretty='format:%s')" \
+      BODY="$(git log -1 --pretty='format:%b')" \
+      node -p 'JSON.stringify({merge_method:"squash",commit_title:process.env.TITLE,commit_message: process.env.BODY})')" > response.json
+    cat response.json
+    if ! commits="$(node -e 'const r=require("./response.json");if(!r.merged)throw new Error("Merging failed");process.stdout.write(r.sha)')"; then
+      commit_queue_failed "$pr"
+      continue
+    fi
   fi
 
   rm output