Go test coverage

SonarQube Server supports the reporting of test coverage information as part of the analysis of your Go project.

However, SonarQube Server does not generate the coverage report itself. Instead, you must set up a third-party tool to produce the report as part of your build process. 

You then need to configure your analysis to tell the SonarScanner where the report is located so that it can pick it up and send it to SonarQube Server, where it will be displayed on your project dashboard along with the other analysis metrics.

For Go projects, SonarQube Server supports the native Go test tooling. 

Adjust your setup

To enable coverage for Go, you need to:

• adjust your build process so that the coverage tool generates the report(s) just after your unit as part of the clean build required to run analysis
• make sure that the coverage tool writes its report file to a defined path in the build environment
• configure the scanning step of your build so that the scanner picks up the report file from that defined path

Adding coverage to your build process

The first step is to generate the coverage reports.

The simplest way to generate a report is to run your test with the -coverprofile=<location> flag.

This will tell the Go tooling to generate a coverage report file at a specific location. For example, go test -coverprofile=coverage.out should generate a coverage.out report in the working directory.

Adding the coverage analysis parameter

The next step is to add sonar.go.coverage.reportPaths to your analysis parameters. This parameter must be set to the path of the report file produced by your coverage tool. The parameter supports the mention of multiple coverage file reports separated by a comma.

In this example, that path is set to the default. It is set in the sonar-project.properties file, located in the project root:

sonar.projectKey=<sonar-project-key>
...
sonar.go.coverage.reportPaths=coverage.xml

Coverage parameters can be set in multiple places

As with other analysis parameters, sonar.go.coverage.reportPaths can be set in multiple places:

• In the sonar-project.properties file, as mentioned above.
• On the command line of the scanner invocation using the -D or --define switch, for example,
  sonar-scanner -Dsonar.go.coverage.reportPaths=coverage.xml
• In the SonarQube Server interface, in the Path to coverage report(s) section under:
  •  Your Project > Project Settings > General Settings > Languages > Go for project-level settings
  • Your Project > Administration > Configuration > General Settings > Languages > Go for global settings (applying to all projects).

Troubleshooting

Missing code coverage for commented-out lines

Users have reported receiving warnings about missing code coverage for lines that are commented out.

When you don’t provide any Go test coverage information, SonarQube estimates that all executable lines of code should be covered by unit tests. Comments are not considered executable lines, and therefore, SonarQube does not expect these lines to be covered by unit tests. Once Go test coverage data is imported into SonarQube, SonarQube fully trusts and displays this data. 

This warning appears because the native Go tooling considers that commented code should be covered. This is a known bug, referenced here. To resolve this, we recommend removing the commented code to eliminate the warning.

Related pages

Test coverage parameters