@ParameterizedTest with @EnumSource are not supported.

[michael-simons]

A parameterized tests with an @EnumSource like this

package org.graalvm.buildtools.example;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.EnumSource;

class App2Test {

	enum Things {
		A, B, C
	}

	@ParameterizedTest
	@EnumSource(Things.class)
	void functionNameSanityCheck(Things thing) {

		Assertions.assertNotNull(thing);
	}

}

fails with

Failures (1):
  JUnit Jupiter:App2Test:functionNameSanityCheck(Things)
    MethodSource [className = 'org.graalvm.buildtools.example.App2Test', methodName = 'functionNameSanityCheck', methodParameterTypes = 'org.graalvm.buildtools.example.App2Test$Things']
    => org.junit.platform.commons.JUnitException: Failed to find a no-argument constructor for ArgumentsProvider [org.junit.jupiter.params.provider.EnumArgumentsProvider]. Please ensure that a no-argument constructor exists and that the class is either a top-level class or a static nested class
       org.junit.jupiter.params.ParameterizedTestExtension.instantiateArgumentsProvider(ParameterizedTestExtension.java:110)
       java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
       java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
       java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1655)
       java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
       [...]
       Suppressed: org.junit.platform.commons.PreconditionViolationException: Configuration error: You must configure at least one set of arguments for this @ParameterizedTest
         org.junit.platform.commons.util.Preconditions.condition(Preconditions.java:281)
         org.junit.jupiter.params.ParameterizedTestExtension.lambda$provideTestTemplateInvocationContexts$6(ParameterizedTestExtension.java:94)
         java.util.stream.AbstractPipeline.close(AbstractPipeline.java:323)
         java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:271)
         [...]
     Caused by: java.lang.NoSuchMethodException: org.junit.jupiter.params.provider.EnumArgumentsProvider.<init>()
       java.lang.Class.getConstructor0(DynamicHub.java:3349)
       java.lang.Class.getDeclaredConstructor(DynamicHub.java:2553)
       org.junit.platform.commons.util.ReflectionUtils.newInstance(ReflectionUtils.java:488)
       org.junit.jupiter.params.ParameterizedTestExtension.instantiateArgumentsProvider(ParameterizedTestExtension.java:102)
       [...]

Applies to 0.9.0 and 0.9.1-SNAPSHOT, tested with GraalVM 21.1.0 JDK 11 in the Maven examples project.

[sbrannen]

As a workaround, running native tests with the agent enabled should hopefully pick up this use of reflection. The agent is supported with Gradle but currently not an option with Maven (see #13).

Another workaround is to manually add the necessary reflection config for the JUnit Jupiter types that are loaded via reflection.

In general, all org.junit.jupiter.params.provider.ArgumentsProvider implementations supported by junit-jupiter-params should be added to the Feature, like with the CsvArgumentsProvider here:

native-build-tools/common/junit-platform-native/src/main/java/org/graalvm/junit/platform/JUnitPlatformFeature.java

Line 84 in acf1474

RuntimeReflection.registerForReflectiveInstantiation(Class.forName("org.junit.jupiter.params.provider.CsvArgumentsProvider"));

However, that would not support a user's custom ArgumentsProvider implementation or those from third parties.

This actually touches on a broader topic that needs to be addressed regarding types loaded via reflection via @ExtendWith, @ArgumentsSource, @EnabledIf, @DisabledIf, @MethodSource, etc. So I'll create another ticket to start the discussion (see #54).