private final FileCollectionInternal collection;
    private final Spec<? super File> filterSpec;

    public FilteredFileCollection(AbstractFileCollection collection, Spec<? super File> filterSpec) {
        super(collection.taskDependencyFactory, collection.patternSetFactory);
        this.collection = collection;
        this.filterSpec = filterSpec;
    }

    @Override

        Runner runner = request.getRunner();

        TestFilterSpec filterSpec = spec.getFilter();
        if (!filterSpec.getIncludedTests().isEmpty()
            || !filterSpec.getIncludedTestsCommandLine().isEmpty()
            || !filterSpec.getExcludedTests().isEmpty()) {
            TestSelectionMatcher matcher = new TestSelectionMatcher(filterSpec);

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class StackTraceFilter {
    private final Spec<StackTraceElement> filterSpec;

    public StackTraceFilter(Spec<StackTraceElement> filterSpec) {
        this.filterSpec = filterSpec;
    }

    // stack traces are filtered in call order (from bottom to top)
    public List<StackTraceElement> filter(List<StackTraceElement> stackTrace) {

        ClassLoader parent = getClass().getClassLoader();
        FilteringClassLoader.Spec filterSpec = new FilteringClassLoader.Spec();
        filterSpec.allowPackage("org.gradle.tooling.internal.protocol");
        filterSpec.allowClass(TaskExecutionRequest.class);
        rootClassLoader = new FilteringClassLoader(parent, filterSpec);
    }

    @Override

            fileCollection.addToAntBuilder(builder, nodeName, AntType.ResourceCollection);
        }
    }

    @Override
    public FileCollectionInternal filter(final Spec<? super File> filterSpec) {
        return new FilteredFileCollection(this, filterSpec) {
            @Override
            protected void appendContents(TreeFormatter formatter) {
                formatter.node("filtered collection");
                formatter.startChildren();

        FilteringClassLoader.Spec filterSpec = new FilteringClassLoader.Spec();
        filterSpec.allowPackage("org.gradle.tooling.internal.protocol");
        filterSpec.allowClass(JavaVersion.class);
        FilteringClassLoader filteringClassLoader = new FilteringClassLoader(classLoader, filterSpec);

        FilteringClassLoader.Spec filterSpec = new FilteringClassLoader.Spec();
        filterSpec.allowPackage("com.sun.tools");
        filterSpec.allowPackage("com.sun.source");
        return classLoaderFactory.createFilteringClassLoader(
            this.getClass().getClassLoader(),
            filterSpec
        );
    }

    public ContextAwareJavaCompiler getSystemJavaCompiler() {

        }
    }

    private List<StackTraceElement> filterStackTrace(Throwable exception, TestDescriptor descriptor) {
        Spec<StackTraceElement> filterSpec = createCompositeFilter(descriptor);
        StackTraceFilter filter = new StackTraceFilter(filterSpec);
        return filter.filter(exception);
    }

    private Spec<StackTraceElement> createCompositeFilter(TestDescriptor descriptor) {

public interface FileCollectionInternal extends FileCollection, TaskDependencyContainer {
    String DEFAULT_COLLECTION_DISPLAY_NAME = "file collection";

    @Override
    FileCollectionInternal filter(Spec<? super File> filterSpec);

    @Override
    FileTreeInternal getAsFileTree();

    /**
     * Returns a copy of this collection, with the given collection replaced with the value returned by the given supplier.
     *

			t.Incomplete = true
		}
	case *ast.MapType:
		r.filterType(nil, t.Key)
		r.filterType(nil, t.Value)
	case *ast.ChanType:
		r.filterType(nil, t.Value)
	}
}

func (r *reader) filterSpec(spec ast.Spec) bool {
	switch s := spec.(type) {
	case *ast.ImportSpec:
		// always keep imports so we can collect them
		return true
	case *ast.ValueSpec: