fix: handle update after force pushing base to a new commit (#1307)

__test__/create-or-update-branch.int.test.ts

@@ -14,7 +14,7 @@ const REMOTE_NAME = 'origin'
 const TRACKED_FILE = 'a/tracked-file.txt'
 const UNTRACKED_FILE = 'b/untracked-file.txt'
 
-const DEFAULT_BRANCH = 'tests/master'
+const DEFAULT_BRANCH = 'tests/main'
 const NOT_BASE_BRANCH = 'tests/branch-that-is-not-the-base'
 const NOT_EXIST_BRANCH = 'tests/branch-that-does-not-exist'
 
@@ -108,10 +108,10 @@ describe('create-or-update-branch tests', () => {
     // Check there are no local changes that might be destroyed by running these tests
     expect(await git.isDirty(true)).toBeFalsy()
     // Fetch the default branch
-    await git.fetch(['master:refs/remotes/origin/master'])
+    await git.fetch(['main:refs/remotes/origin/main'])
 
     // Create a "not base branch" for the test run
-    await git.checkout('master')
+    await git.checkout('main')
     await git.checkout(NOT_BASE_BRANCH, 'HEAD')
     await createFile(TRACKED_FILE)
     await git.exec(['add', '-A'])
@@ -123,7 +123,7 @@ describe('create-or-update-branch tests', () => {
     ])
 
     // Create a new default branch for the test run with a tracked file
-    await git.checkout('master')
+    await git.checkout('main')
     await git.checkout(DEFAULT_BRANCH, 'HEAD')
     await createFile(TRACKED_FILE)
     await git.exec(['add', '-A'])
@@ -631,6 +631,69 @@ describe('create-or-update-branch tests', () => {
     ).toBeTruthy()
   })
 
+  it('tests create, force push of base branch, and update with identical changes', async () => {
+    // If the base branch is force pushed to a different commit when there is an open
+    // pull request, the branch must be reset to rebase the changes on the base.
+
+    // Create tracked and untracked file changes
+    const changes = await createChanges()
+    const commitMessage = uuidv4()
+    const result = await createOrUpdateBranch(
+      git,
+      commitMessage,
+      '',
+      BRANCH,
+      REMOTE_NAME,
+      false,
+      ADD_PATHS_DEFAULT
+    )
+    expect(result.action).toEqual('created')
+    expect(await getFileContent(TRACKED_FILE)).toEqual(changes.tracked)
+    expect(await getFileContent(UNTRACKED_FILE)).toEqual(changes.untracked)
+    expect(
+      await gitLogMatches([commitMessage, INIT_COMMIT_MESSAGE])
+    ).toBeTruthy()
+
+    // Push pull request branch to remote
+    await git.push([
+      '--force-with-lease',
+      REMOTE_NAME,
+      `HEAD:refs/heads/${BRANCH}`
+    ])
+
+    await afterTest(false)
+    await beforeTest()
+
+    // Force push the base branch to a different commit
+    const amendedCommitMessage = uuidv4()
+    await git.commit(['--amend', '-m', amendedCommitMessage])
+    await git.push([
+      '--force',
+      REMOTE_NAME,
+      `HEAD:refs/heads/${DEFAULT_BRANCH}`
+    ])
+
+    // Create the same tracked and untracked file changes (no change on update)
+    const _changes = await createChanges(changes.tracked, changes.untracked)
+    const _commitMessage = uuidv4()
+    const _result = await createOrUpdateBranch(
+      git,
+      _commitMessage,
+      '',
+      BRANCH,
+      REMOTE_NAME,
+      false,
+      ADD_PATHS_DEFAULT
+    )
+    expect(_result.action).toEqual('updated')
+    expect(_result.hasDiffWithBase).toBeTruthy()
+    expect(await getFileContent(TRACKED_FILE)).toEqual(_changes.tracked)
+    expect(await getFileContent(UNTRACKED_FILE)).toEqual(_changes.untracked)
+    expect(
+      await gitLogMatches([_commitMessage, amendedCommitMessage])
+    ).toBeTruthy()
+  })
+
   it('tests create and update with commits on the working base (during the workflow)', async () => {
     // Create commits on the working base
     const commits = await createCommits(git)
@@ -1519,6 +1582,75 @@ describe('create-or-update-branch tests', () => {
     ).toBeTruthy()
   })
 
+  it('tests create, force push of base branch, and update with identical changes (WBNB)', async () => {
+    // If the base branch is force pushed to a different commit when there is an open
+    // pull request, the branch must be reset to rebase the changes on the base.
+
+    // Set the working base to a branch that is not the pull request base
+    await git.checkout(NOT_BASE_BRANCH)
+
+    // Create tracked and untracked file changes
+    const changes = await createChanges()
+    const commitMessage = uuidv4()
+    const result = await createOrUpdateBranch(
+      git,
+      commitMessage,
+      BASE,
+      BRANCH,
+      REMOTE_NAME,
+      false,
+      ADD_PATHS_DEFAULT
+    )
+    expect(result.action).toEqual('created')
+    expect(await getFileContent(TRACKED_FILE)).toEqual(changes.tracked)
+    expect(await getFileContent(UNTRACKED_FILE)).toEqual(changes.untracked)
+    expect(
+      await gitLogMatches([commitMessage, INIT_COMMIT_MESSAGE])
+    ).toBeTruthy()
+
+    // Push pull request branch to remote
+    await git.push([
+      '--force-with-lease',
+      REMOTE_NAME,
+      `HEAD:refs/heads/${BRANCH}`
+    ])
+
+    await afterTest(false)
+    await beforeTest()
+
+    // Force push the base branch to a different commit
+    const amendedCommitMessage = uuidv4()
+    await git.commit(['--amend', '-m', amendedCommitMessage])
+    await git.push([
+      '--force',
+      REMOTE_NAME,
+      `HEAD:refs/heads/${DEFAULT_BRANCH}`
+    ])
+
+    // Set the working base to a branch that is not the pull request base
+    await git.checkout(NOT_BASE_BRANCH)
+
+    // Create the same tracked and untracked file changes (no change on update)
+    const _changes = await createChanges(changes.tracked, changes.untracked)
+    const _commitMessage = uuidv4()
+    const _result = await createOrUpdateBranch(
+      git,
+      _commitMessage,
+      BASE,
+      BRANCH,
+      REMOTE_NAME,
+      false,
+      ADD_PATHS_DEFAULT
+    )
+    expect(_result.action).toEqual('updated')
+    expect(_result.hasDiffWithBase).toBeTruthy()
+    expect(await getFileContent(TRACKED_FILE)).toEqual(_changes.tracked)
+    expect(await getFileContent(UNTRACKED_FILE)).toEqual(_changes.untracked)
+    expect(
+      await gitLogMatches([_commitMessage, amendedCommitMessage])
+    ).toBeTruthy()
+  })
+
   it('tests create and update with commits on the working base (during the workflow) (WBNB)', async () => {
     // Set the working base to a branch that is not the pull request base
     await git.checkout(NOT_BASE_BRANCH)

__test__/entrypoint.sh

@@ -6,6 +6,7 @@ WORKINGDIR=$PWD
 
 # Create and serve a remote repo
 mkdir -p /git/remote
+git config --global init.defaultBranch main
 git init --bare /git/remote/test-base.git
 git daemon --verbose --enable=receive-pack --base-path=/git/remote --export-all /git/remote &>/dev/null &
 

dist/index.js

@@ -74,18 +74,30 @@ function tryFetch(git, remote, branch) {
     });
 }
 exports.tryFetch = tryFetch;
+// Return the number of commits that branch2 is ahead of branch1
+function commitsAhead(git, branch1, branch2) {
+    return __awaiter(this, void 0, void 0, function* () {
+        const result = yield git.revList([`${branch1}...${branch2}`], ['--right-only', '--count']);
+        return Number(result);
+    });
+}
 // Return true if branch2 is ahead of branch1
 function isAhead(git, branch1, branch2) {
     return __awaiter(this, void 0, void 0, function* () {
-        const result = yield git.revList([`${branch1}...${branch2}`], ['--right-only', '--count']);
-        return Number(result) > 0;
+        return (yield commitsAhead(git, branch1, branch2)) > 0;
+    });
+}
+// Return the number of commits that branch2 is behind branch1
+function commitsBehind(git, branch1, branch2) {
+    return __awaiter(this, void 0, void 0, function* () {
+        const result = yield git.revList([`${branch1}...${branch2}`], ['--left-only', '--count']);
+        return Number(result);
     });
 }
 // Return true if branch2 is behind branch1
 function isBehind(git, branch1, branch2) {
     return __awaiter(this, void 0, void 0, function* () {
-        const result = yield git.revList([`${branch1}...${branch2}`], ['--left-only', '--count']);
-        return Number(result) > 0;
+        return (yield commitsBehind(git, branch1, branch2)) > 0;
     });
 }
 // Return true if branch2 is even with branch1
@@ -214,9 +226,16 @@ function createOrUpdateBranch(git, commitMessage, base, branch, branchRemoteName
             //   branches after merging. In particular, it catches a case where the branch was
             //   squash merged but not deleted. We need to reset to make sure it doesn't appear
             //   to have a diff with the base due to different commits for the same changes.
+            // - If the number of commits ahead of the base branch differs between the branch and
+            //   temp branch. This catches a case where the base branch has been force pushed to
+            //   a new commit.
             // For changes on base this reset is equivalent to a rebase of the pull request branch.
+            const tempBranchCommitsAhead = yield commitsAhead(git, base, tempBranch);
+            const branchCommitsAhead = yield commitsAhead(git, base, branch);
             if ((yield git.hasDiff([`${branch}..${tempBranch}`])) ||
-                !(yield isAhead(git, base, tempBranch))) {
+                branchCommitsAhead != tempBranchCommitsAhead ||
+                !(tempBranchCommitsAhead > 0) // !isAhead
+            ) {
                 core.info(`Resetting '${branch}'`);
                 // Alternatively, git switch -C branch tempBranch
                 yield git.checkout(branch, tempBranch);

docs/concepts-guidelines.md

@@ -214,8 +214,9 @@ How to use SSH (deploy keys) with create-pull-request action:
 
 Instead of pushing pull request branches to the repository you want to update, you can push them to a fork of that repository.
 This allows you to employ the [principle of least privilege](https://en.wikipedia.org/wiki/Principle_of_least_privilege) by using a dedicated user acting as a [machine account](https://docs.github.com/en/github/site-policy/github-terms-of-service#3-account-requirements).
-This user has no access to the main repository.
+This user only has `read` access to the main repository.
 It will use their own fork to push code and create the pull request.
+Note that if you choose to use this method (not give the machine account `write` access to the repository) the following inputs cannot be used: `labels`, `assignees`, `reviewers`, `team-reviewers` and `milestone`.
 
 1. Create a new GitHub user and login.
 2. Fork the repository that you will be creating pull requests in.

docs/examples.md

@@ -282,8 +282,10 @@ jobs:
       - name: Get Latest Swagger UI Release
         id: swagger-ui
         run: |
-          echo ::set-output name=release_tag::$(curl -sL https://api.github.com/repos/swagger-api/swagger-ui/releases/latest | jq -r ".tag_name")
-          echo ::set-output name=current_tag::$(<swagger-ui.version)
+          release_tag=$(curl -sL https://api.github.com/repos/swagger-api/swagger-ui/releases/latest | jq -r ".tag_name")
+          echo "release_tag=$release_tag" >> $GITHUB_OUTPUT
+          current_tag=$(<swagger-ui.version)
+          echo "current_tag=$current_tag" >> $GITHUB_OUTPUT
       - name: Update Swagger UI
         if: steps.swagger-ui.outputs.current_tag != steps.swagger-ui.outputs.release_tag
         env:
@@ -475,7 +477,9 @@ jobs:
           args: --exit-code --recursive --in-place --aggressive --aggressive .
       - name: Set autopep8 branch name
         id: vars
-        run: echo ::set-output name=branch-name::"autopep8-patches/${{ github.head_ref }}"
+        run: |
+          branch-name="autopep8-patches/${{ github.head_ref }}"
+          echo "branch-name=$branch-name" >> $GITHUB_OUTPUT
       - name: Create Pull Request
         if: steps.autopep8.outputs.exit-code == 2
         uses: peter-evans/create-pull-request@v4
@@ -525,16 +529,17 @@ jobs:
 ### Dynamic configuration using variables
 
 The following examples show how configuration for the action can be dynamically defined in a previous workflow step.
-
-The recommended method is to use [`set-output`](https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-output-parameter). Note that the step where output variables are defined must have an id.
+Note that the step where output variables are defined must have an id.
 
 ```yml
       - name: Set output variables
         id: vars
         run: |
-          echo ::set-output name=pr_title::"[Test] Add report file $(date +%d-%m-%Y)"
-          echo ::set-output name=pr_body::"This PR was auto-generated on $(date +%d-%m-%Y) \
+          pr_title="[Test] Add report file $(date +%d-%m-%Y)"
+          pr_body="This PR was auto-generated on $(date +%d-%m-%Y) \
             by [create-pull-request](https://github.com/peter-evans/create-pull-request)."
+          echo "pr_title=$pr_title" >> $GITHUB_OUTPUT
+          echo "pr_body=$pr_body" >> $GITHUB_OUTPUT
       - name: Create Pull Request
         uses: peter-evans/create-pull-request@v4
         with:
@@ -545,16 +550,15 @@ The recommended method is to use [`set-output`](https://docs.github.com/en/actio
 ### Setting the pull request body from a file
 
 This example shows how file content can be read into a variable and passed to the action.
-The content must be [escaped to preserve newlines](https://github.community/t/set-output-truncates-multiline-strings/16852/3).
 
 ```yml
       - id: get-pr-body
         run: |
           body=$(cat pr-body.txt)
-          body="${body//'%'/'%25'}"
-          body="${body//$'\n'/'%0A'}"
-          body="${body//$'\r'/'%0D'}" 
-          echo ::set-output name=body::$body
+          delimiter="$(openssl rand -hex 8)"
+          echo "body<<$delimiter" >> $GITHUB_OUTPUT
+          echo "$body" >> $GITHUB_OUTPUT
+          echo "$delimiter" >> $GITHUB_OUTPUT
 
       - name: Create Pull Request
         uses: peter-evans/create-pull-request@v4

src/create-or-update-branch.ts

@@ -43,17 +43,39 @@ export async function tryFetch(
   }
 }
 
+// Return the number of commits that branch2 is ahead of branch1
+async function commitsAhead(
+  git: GitCommandManager,
+  branch1: string,
+  branch2: string
+): Promise<number> {
+  const result = await git.revList(
+    [`${branch1}...${branch2}`],
+    ['--right-only', '--count']
+  )
+  return Number(result)
+}
+
 // Return true if branch2 is ahead of branch1
 async function isAhead(
   git: GitCommandManager,
   branch1: string,
   branch2: string
 ): Promise<boolean> {
+  return (await commitsAhead(git, branch1, branch2)) > 0
+}
+
+// Return the number of commits that branch2 is behind branch1
+async function commitsBehind(
+  git: GitCommandManager,
+  branch1: string,
+  branch2: string
+): Promise<number> {
   const result = await git.revList(
     [`${branch1}...${branch2}`],
-    ['--right-only', '--count']
+    ['--left-only', '--count']
   )
-  return Number(result) > 0
+  return Number(result)
 }
 
 // Return true if branch2 is behind branch1
@@ -62,11 +84,7 @@ async function isBehind(
   branch1: string,
   branch2: string
 ): Promise<boolean> {
-  const result = await git.revList(
-    [`${branch1}...${branch2}`],
-    ['--left-only', '--count']
-  )
-  return Number(result) > 0
+  return (await commitsBehind(git, branch1, branch2)) > 0
 }
 
 // Return true if branch2 is even with branch1
@@ -226,10 +244,16 @@ export async function createOrUpdateBranch(
     //   branches after merging. In particular, it catches a case where the branch was
     //   squash merged but not deleted. We need to reset to make sure it doesn't appear
     //   to have a diff with the base due to different commits for the same changes.
+    // - If the number of commits ahead of the base branch differs between the branch and
+    //   temp branch. This catches a case where the base branch has been force pushed to
+    //   a new commit.
     // For changes on base this reset is equivalent to a rebase of the pull request branch.
+    const tempBranchCommitsAhead = await commitsAhead(git, base, tempBranch)
+    const branchCommitsAhead = await commitsAhead(git, base, branch)
     if (
       (await git.hasDiff([`${branch}..${tempBranch}`])) ||
-      !(await isAhead(git, base, tempBranch))
+      branchCommitsAhead != tempBranchCommitsAhead ||
+      !(tempBranchCommitsAhead > 0) // !isAhead
     ) {
       core.info(`Resetting '${branch}'`)
       // Alternatively, git switch -C branch tempBranch