Flutter Integration with Mergify

This guide shows how to generate a JUnit report from the tests of your Flutter app, run with flutter test, and upload it to Test Engine from your CI workflow.

For a Dart package without Flutter, see the Dart guide.

flutter test has no JUnit output of its own. It writes its results as JSON, which the junitreport package converts to JUnit XML.

Install the converter once on the machine that runs your tests:

dart pub global activate junitreport

Run your tests with a JSON file reporter. --file-reporter writes the JSON to a file and keeps the usual output in your terminal:

flutter test --file-reporter json:test-results.json

Then convert the JSON to JUnit XML, passing your checkout’s path as --base:

dart pub global run junitreport:tojunit --base "$PWD/" --input test-results.json --output junit.xml

flutter test records each test file by its absolute path. --base strips your checkout’s path from it, so test names do not change with the directory your CI checks the repository out to.

Run the conversion even when tests fail: flutter test exits with a non-zero status then, and the conversion is what writes the report you upload.

Run the tests in a step with an id, convert their results, and let the upload step decide the job’s result:

- name: Install junitreport
  run: dart pub global activate junitreport

- name: Run Flutter Tests
  id: tests
  continue-on-error: true
  run: flutter test --file-reporter json:test-results.json

- name: Convert the results to JUnit
  run: dart pub global run junitreport:tojunit --base "$PWD/" --input test-results.json --output junit.xml

- name: Mergify CI Upload
  if: success() || failure()
  uses: mergifyio/gha-mergify-ci@v27
  with:
    token: ${{ secrets.MERGIFY_TOKEN }}
    report_path: junit.xml
    test_step_outcome: ${{ steps.tests.outcome }}

Key Points:

• if: success() || failure(): Runs the upload step even if tests fail, ensuring Test Engine has the full report.
• report_path: junit.xml: Points to where your JUnit file is located. Make sure it matches the path you set in your CI job.
• test_step_outcome: ${{ steps.tests.outcome }}: Passes the test runner step's outcome so Mergify can detect silent failures where the runner crashed but the JUnit report appears clean. Add an id (such as tests) to your test runner step and update the steps.<id>.outcome reference to match.
• On pull requests from forks and from Dependabot, MERGIFY_TOKEN is empty and this step fails: skip it as shown in Pull Requests Without the Secret.

If you use a job matrix in your workflow (e.g., to test across multiple versions), every leg reports the same job name, because GitHub Actions gives them all one GITHUB_JOB. Set the job_name input so Test Engine can tell the reports apart:

jobs:
  example_matrix:
    strategy:
      matrix:
        version: [10, 12, 14]

Your upload step should look like:

- name: Mergify CI Upload
  if: success() || failure()
  uses: mergifyio/gha-mergify-ci@v27
  with:
    job_name: example_matrix (${{ matrix.version }})
    token: ${{ secrets.MERGIFY_TOKEN }}
    report_path: junit.xml
    test_step_outcome: ${{ steps.tests.outcome }}

To benefit from Test Engine quarantine, you need to add continue-on-error: true in your GitHub Actions step that executes your tests and generates the JUnit file. The step running the gha-mergify-ci action then decides whether the job passes or fails, taking quarantined tests into account.

You should also pass test_step_outcome: ${{ steps.tests.outcome }} to the step that runs mergifyio/gha-mergify-ci (where tests is the id of your test runner step) to detect silent failures where the test runner crashed but the JUnit report appears clean. Without this input, a crash that produces a partial or empty report could be mistakenly treated as a success.

With continue-on-error: true, the job’s result comes from the upload step. On pull requests from forks and from Dependabot, MERGIFY_TOKEN is empty and the upload step has to be skipped: add the step that fails the job when the tests failed and nothing was uploaded, as shown in pull requests without the secret.

Run the conversion in your step’s command, after the tests, so it runs whatever their outcome, and exit with the tests’ status:

dart pub global activate junitreport
status=0
flutter test --file-reporter json:test-results.json || status=$?
dart pub global run junitreport:tojunit --base "$PWD/" --input test-results.json --output junit.xml
exit $status

steps:
  - label: "Run tests"
    command: <your test command>
    plugins:
      - mergifyio/mergify-ci#v8:
          action: junit-process
          report_path: junit.xml

Key Points:

• The plugin runs in the post-command hook, so it uploads results after your tests finish, even if they fail.
• report_path: junit.xml: Points to where your JUnit file is located. Make sure it matches the path you set in your test configuration.
• Silent failure detection is automatic: the plugin reads the step's exit code to detect cases where the test runner crashed but the JUnit report appears clean.

If you use a build matrix in your pipeline, each variation reports its own step label as its job name, so the variations are already distinct. Set the job_name plugin property when the label is not the name you want Test Engine to file the reports under:

steps:
  - label: "Flaky detection ({{matrix}})"
    matrix:
      - "3.10"
      - "3.11"
      - "3.12"
    command: <your test command>
    plugins:
      - mergifyio/mergify-ci#v8:
          action: junit-process
          job_name: "Tests ({{matrix}})"
          report_path: junit.xml

When using the Buildkite plugin for Test Engine quarantine, the plugin automatically detects test failures using the step’s exit code. No extra configuration is needed.

The mergifyio/mergify-ci plugin runs in the post-command hook and reads BUILDKITE_COMMAND_EXIT_STATUS to detect silent failures where the test runner crashed but the JUnit report appears clean.

Install the Mergify CLI in your pipeline and export MERGIFY_TOKEN. Run the conversion between your tests and mergify ci junit-process:

set -o pipefail
exit_code=0
flutter test --file-reporter json:test-results.json || exit_code=$?
dart pub global run junitreport:tojunit --base "$PWD/" --input test-results.json --output junit.xml
mergify ci junit-process \
  --test-exit-code "$exit_code" \
  junit.xml

--test-exit-code passes the tests’ status to Mergify, which uses it to catch a run that crashed but left a clean report behind. junit-process exits last, so its status, which accounts for quarantined tests, becomes the step’s.

Test Engine names each test by its file’s path without _test.dart, dotted, then a dot and its groups and description, joined with spaces: the test 'adds an item' inside group('add()') inside group('Cart') of test/cart_test.dart is reported as test.cart.Cart add() adds an item. Moving or renaming the file, a group or the test starts a new history for it.

Widget tests are named the same way: testWidgets('Counter increments smoke test') in test/widget_test.dart is reported as test.widget.Counter increments smoke test.

After pushing these changes:

1. Your CI workflow runs your Flutter tests.
2. flutter test writes its results to test-results.json, and tojunit converts them to junit.xml.
3. Mergify uploads the report to Test Engine.

You can then review your test results, including any failures or flaky tests, directly in the Test Engine dashboard.

• Test names hold a path such as .home.runner.work: pass --base "$PWD/" to tojunit, from the root of your checkout.

• Report not found when tests fail: check that the conversion runs after a failed test run, as in the examples above.

• The CLI provides information about the upload. Check the logs in GitHub Actions.
• File paths: Double-check that the output file matches the path used in report_path.
• Permissions: Make sure the MERGIFY_TOKEN is valid and setup in your GitHub Actions secrets as explained in the docs.
• Workflow conditions: If your step is not running, confirm the if condition is actually triggered in your job.