Swift Testing

A guide for generating Trunk-compatible test reports with Swift Testing

You can automatically detect and manage flaky tests in your Swift projects by integrating with Trunk. This document explains how to configure Swift Testing to output JUnit XML reports that can be uploaded to Trunk for analysis.

Checklist

By the end of this guide, you should achieve the following before proceeding to the next steps to configure your CI provider.

• Generate a compatible test report
• Configure the report file path or glob
• Disable retries for better detection accuracy
• Test uploads locally

After correctly generating reports following the above steps, you’ll be ready to move on to the next steps to configure uploads in CI.

Generating Reports

Trunk detects flaky tests by analyzing test reports automatically uploaded from your CI jobs. You can do this by generating Trunk-compatible XML reports from your test runs.

To output a compatible report, add the --xunit-output argument to your Swift test command:

swift test --xunit-output junit.xml --parallel

Due to a known bug with Swift, you must include the --parallel flag for the XML report to output properly.

Report File Path

The test report will be written to the location specified by the --xunit-output argument. In the example above, it would be at ./junit.xml.

Disable Retries

You need to disable automatic retries if you previously enabled them. Retries compromise the accurate detection of flaky tests.

Swift Testing doesn’t support retries out of the box, but if you implemented retries or imported a package, remember to disable them.

Try It Locally

The Validate Command

You can validate your test reports using the Trunk CLI. If you don’t have it installed already, you can install and run the validate command like this:

Linux (x64)

SKU="trunk-analytics-cli-x86_64-unknown-linux.tar.gz"
curl -fL --retry 3 \
  "https://github.com/trunk-io/analytics-cli/releases/latest/download/${SKU}" \
  | tar -xz

chmod +x trunk-analytics-cli
./trunk-analytics-cli validate --junit-paths "./junit.xml"

Linux (arm64)

SKU="trunk-analytics-cli-aarch64-unknown-linux.tar.gz"
curl -fL --retry 3 \
  "https://github.com/trunk-io/analytics-cli/releases/latest/download/${SKU}" \
  | tar -xz

chmod +x trunk-analytics-cli
./trunk-analytics-cli validate --junit-paths "./junit.xml"

macOS (arm64)

SKU="trunk-analytics-cli-aarch64-apple-darwin.tar.gz"
curl -fL --retry 3 \
  "https://github.com/trunk-io/analytics-cli/releases/latest/download/${SKU}" \
  | tar -xz

chmod +x trunk-analytics-cli
./trunk-analytics-cli validate --junit-paths "./junit.xml"

macOS (x64)

SKU="trunk-analytics-cli-x86_64-apple-darwin.tar.gz"
curl -fL --retry 3 \
  "https://github.com/trunk-io/analytics-cli/releases/latest/download/${SKU}" \
  | tar -xz

chmod +x trunk-analytics-cli
./trunk-analytics-cli validate --junit-paths "./junit.xml"

This will not upload anything to Trunk. To improve detection accuracy, you should address all errors and warnings before proceeding to the next steps.

Test Upload

Before modifying your CI jobs to automatically upload test results to Trunk, try uploading a single test run manually.

You make an upload to Trunk using the following command:

./trunk-analytics-cli upload --junit-paths "./junit.xml" \
    --org-url-slug <TRUNK_ORG_SLUG> \
    --token <TRUNK_ORG_TOKEN>

You can find your Trunk organization slug and token in the settings or by following these instructions. After your upload, you can verify that Trunk has received and processed it successfully in the Uploads tab. Warnings will be displayed if the report has issues.

Next Steps

Configure your CI to upload test runs to Trunk. Find the guides for your CI framework below:

Azure DevOps Pipelines		azure-devops-pipelines	azure.png
BitBucket Pipelines		bitbucket-pipelines	bitbucket.png
BuildKite		buildkite	buildkite.png
CircleCI		circleci	circle-ci.png
Drone CI		droneci	drone.png
GitHub Actions		github-actions	github.png
Gitlab		gitlab	gitlab.png
Jenkins		jenkins	jenkins.png
Semaphore		semaphoreci	semaphore.png
TeamCity		https://github.com/trunk-io/docs/blob/main/flaky-tests/get-started/frameworks/broken-reference/README.md	teamcity.png
Travis CI		travisci	travis.png
Other CI Providers		otherci	other.png