From cad7fb99ccede90bbe9098ce94d85a448bb234f2 Mon Sep 17 00:00:00 2001
From: Antoine du Hamel <duhamelantoine1995@gmail.com>
Date: Sat, 23 Oct 2021 18:17:23 +0200
Subject: [PATCH] tools: abort CQ session when landing several commits

Most PRs are meant to be squashed in one commit when landing. If the
collaborator hasn't been using `fixup!` commits, the CQ lands the PR
as several commits. This change makes the CQ abort by default
when attempting to land several commits, unless there's another
label added to the PR to force squashing or landing as several commits.

Fixes: https://github.com/nodejs/node/issues/40436
Refs: https://github.com/nodejs/node-core-utils/pull/572

PR-URL: https://github.com/nodejs/node/pull/40577
---
 doc/guides/commit-queue.md    |  8 +++++++-
 tools/actions/commit-queue.sh | 10 +++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/doc/guides/commit-queue.md b/doc/guides/commit-queue.md
index dec153196ea..d7ecef57c50 100644
--- a/doc/guides/commit-queue.md
+++ b/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
diff --git a/tools/actions/commit-queue.sh b/tools/actions/commit-queue.sh
index 22f306cc36b..7272c71b4db 100755
--- a/tools/actions/commit-queue.sh
+++ b/tools/actions/commit-queue.sh
@@ -70,7 +70,15 @@ 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