Test validation

How newly created tests are validated by Diffblue Cover CLI. (Any tests that fail compilation or execution are removed.)

After tests have been generated, Cover validates newly created tests by invoking the test phase of your build tool (Maven, Gradle). Cover will then remove any created tests that fail compilation or execution.

• Existing unit tests must compile and pass (mvn test, gradle test) before dcover create is invoked.

• If unvalidated JUnit 5 tests (those which fail to compile or run successfully) are generated by dcover create, please confirm that running mvn test actually executes your unit tests. JUnit 5 requires at minimum Maven Surefire v2.22.0 to work, and if an older version is present mvn test will pass without executing any tests. You can specify the Surefire Plugin version in your POM using:

  <build>
    <plugins>
      <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.2</version>
      </plugin>
    </plugins>
  </build>

• When running mvn test, dcover can disable known style checking plugins (checkstyle, spring-javaformat) by using the --ignore-stylechecks argument.

• Test validation is bypassed if a build tool (Maven, Gradle) is not detected from your environment. In that case it is possible that some created tests may fail compilation or execution.

Test Validation and user-specified system properties

The -D or --define option allows you to pass additional system properties to dcover for test creation and execution.

Any created tests may depend upon these user-specified system properties and may not execute successfully without them.

During test validation dcover will forward user-specified system properties to your build tool, be that Maven or Gradle.

Maven is able to utilize these forwarded properties when executing tests for test validation. No configuration is required.

However Gradle does not forward system properties to executed tests and will require further configuration to do so. In such a case test validation is likely to fail out-of-the-box without changes to your build script (build.gradle or build.gradle.kts).

In any case, for Maven and Gradle you will need to configure test execution in your build script to supply these same user-specified system properties when executing those tests outside dcover.

For more details about build tool configuration with system properties, see the Maven and Gradle topics.