Very basic implementation

surefire-junit5/build.gradle

@@ -1,5 +1,6 @@
 dependencies {
 	compile('org.apache.maven.surefire:surefire-api:2.19')
+	compile('org.apache.maven.surefire:common-java5:2.19')
 	compile(project(':junit-launcher'))
 	runtime(project(':junit5-engine'))
 	runtime(project(':junit4-engine'))

surefire-junit5/src/main/java/org/junit/gen5/surefire/AcceptAllClassesScannerFilter.java

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2015 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.junit.gen5.surefire;
+
+import org.apache.maven.surefire.util.ScannerFilter;
+
+final class AcceptAllClassesScannerFilter implements ScannerFilter {
+
+	@SuppressWarnings("rawtypes")
+	@Override
+	public boolean accept(Class testClass) {
+		return true;
+	}
+}

surefire-junit5/src/main/java/org/junit/gen5/surefire/JUnitGen5Provider.java

@@ -1,31 +1,91 @@
+/*
+ * Copyright 2015 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
 
 package org.junit.gen5.surefire;
 
+import static org.junit.gen5.engine.TestPlanSpecification.build;
+
 import java.lang.reflect.InvocationTargetException;
 
 import org.apache.maven.surefire.providerapi.AbstractProvider;
 import org.apache.maven.surefire.providerapi.ProviderParameters;
 import org.apache.maven.surefire.report.ReporterException;
+import org.apache.maven.surefire.report.ReporterFactory;
+import org.apache.maven.surefire.report.RunListener;
+import org.apache.maven.surefire.report.SimpleReportEntry;
 import org.apache.maven.surefire.suite.RunResult;
 import org.apache.maven.surefire.testset.TestSetFailedException;
+import org.apache.maven.surefire.util.TestsToRun;
+import org.junit.gen5.engine.TestPlanSpecification;
+import org.junit.gen5.launcher.Launcher;
 
 public class JUnitGen5Provider extends AbstractProvider {
 
-	public JUnitGen5Provider(ProviderParameters booterParameters) {
-		// TODO Implement this.
+	private final ProviderParameters parameters;
+
+	public JUnitGen5Provider(ProviderParameters parameters) {
+		this.parameters = parameters;
 	}
 
 	@Override
 	public Iterable<Class<?>> getSuites() {
 		// TODO Implement this.
-		return null;
+		throw new UnsupportedOperationException("Not yet supported.");
 	}
 
 	@Override
 	public RunResult invoke(Object forkTestSet)
 			throws TestSetFailedException, ReporterException, InvocationTargetException {
-		// TODO Implement this.
-		throw new TestSetFailedException("Hello from JUnit5!");
+		if (forkTestSet != null) {
+			// TODO Implement this.
+			throw new UnsupportedOperationException("Not yet supported.");
+		}
+
+		TestsToRun testsToRun = scanClasspath();
+		return invoke(testsToRun);
+	}
+
+	private RunResult invoke(TestsToRun testsToRun) {
+		RunResult runResult;
+		ReporterFactory reporterFactory = parameters.getReporterFactory();
+		try {
+			RunListener runListener = reporterFactory.createReporter();
+
+			Launcher launcher = new Launcher();
+			launcher.registerTestPlanExecutionListeners(new RunListenerAdapter(runListener));
+
+			for (Class<?> testClass : testsToRun) {
+				invoke(testClass, launcher, runListener);
+			}
+		}
+		finally {
+			runResult = reporterFactory.close();
+		}
+		return runResult;
+	}
+
+	private TestsToRun scanClasspath() {
+		TestsToRun scannedClasses = parameters.getScanResult().applyFilter(new AcceptAllClassesScannerFilter(),
+			parameters.getTestClassLoader());
+		TestsToRun orderedClasses = parameters.getRunOrderCalculator().orderTestClasses(scannedClasses);
+		return orderedClasses;
+	}
+
+	private void invoke(Class<?> testClass, Launcher launcher, RunListener runListener) {
+		SimpleReportEntry classEntry = new SimpleReportEntry(getClass().getName(), testClass.getName());
+		runListener.testSetStarting(classEntry);
+
+		TestPlanSpecification specification = build(TestPlanSpecification.forClass(testClass));
+		launcher.execute(specification);
+
+		runListener.testSetCompleted(classEntry);
 	}
 
 }

surefire-junit5/src/main/java/org/junit/gen5/surefire/RunListenerAdapter.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2015 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.junit.gen5.surefire;
+
+import static org.apache.maven.surefire.report.SimpleReportEntry.ignored;
+
+import java.util.Optional;
+
+import org.apache.maven.surefire.report.PojoStackTraceWriter;
+import org.apache.maven.surefire.report.RunListener;
+import org.apache.maven.surefire.report.SimpleReportEntry;
+import org.apache.maven.surefire.report.StackTraceWriter;
+import org.junit.gen5.engine.JavaSource;
+import org.junit.gen5.engine.TestDescriptor;
+import org.junit.gen5.engine.TestExecutionListener;
+import org.junit.gen5.engine.TestSource;
+
+final class RunListenerAdapter implements TestExecutionListener {
+
+	private RunListener runListener;
+
+	public RunListenerAdapter(RunListener reporter) {
+		this.runListener = reporter;
+	}
+
+	@Override
+	public void testStarted(TestDescriptor testDescriptor) {
+		runListener.testStarting(new SimpleReportEntry(getClassName(testDescriptor), testDescriptor.getDisplayName()));
+	}
+
+	@Override
+	public void testSkipped(TestDescriptor testDescriptor, Throwable t) {
+		StackTraceWriter stackTraceWriter = getStackTraceWriter(testDescriptor, t);
+		runListener.testSkipped(ignored(getClassName(testDescriptor), testDescriptor.getDisplayName(), t.getMessage()));
+	}
+
+	@Override
+	public void testAborted(TestDescriptor testDescriptor, Throwable t) {
+		StackTraceWriter stackTraceWriter = getStackTraceWriter(testDescriptor, t);
+		runListener.testAssumptionFailure(
+			ignored(getClassName(testDescriptor), testDescriptor.getDisplayName(), t.getMessage()));
+	}
+
+	@Override
+	public void testFailed(TestDescriptor testDescriptor, Throwable t) {
+		StackTraceWriter stackTraceWriter = getStackTraceWriter(testDescriptor, t);
+		runListener.testFailed(new SimpleReportEntry(getClassName(testDescriptor), testDescriptor.getDisplayName(),
+			stackTraceWriter, null));
+	}
+
+	@Override
+	public void testSucceeded(TestDescriptor testDescriptor) {
+		runListener.testSucceeded(new SimpleReportEntry(getClassName(testDescriptor), testDescriptor.getDisplayName()));
+	}
+
+	private StackTraceWriter getStackTraceWriter(TestDescriptor testDescriptor, Throwable t) {
+		return new PojoStackTraceWriter(getClassName(testDescriptor), testDescriptor.getDisplayName(), t);
+	}
+
+	private String getClassName(TestDescriptor testDescriptor) {
+		Optional<TestSource> testSource = testDescriptor.getSource();
+		if (testSource.isPresent() && testSource.get() instanceof JavaSource) {
+			JavaSource javaSource = (JavaSource) testSource.get();
+			if (javaSource.getJavaClass().isPresent()) {
+				return javaSource.getJavaClass().get().getName();
+			}
+		}
+		return testDescriptor.getUniqueId();
+	}
+}