Implement JUnit test engine

gradle/libs.versions.toml

@@ -11,11 +11,14 @@ groovy = "org.apache.groovy:groovy:4.0.29"
 junit4 = "junit:junit:4.13.2"
 junit-vintage = { module = "org.junit.vintage:junit-vintage-engine", version.ref = "junit-vintage" }
 junit-launcher = { module = "org.junit.platform:junit-platform-launcher", version.ref = "junit-launcher" }
+junit-engine = { module = "org.junit.platform:junit-platform-engine", version.ref = "junit-launcher" }
+junit-jupiter-api = { module = "org.junit.jupiter:junit-jupiter-api", version.ref = "junit-launcher" }
+junit-jupiter-engine = { module = "org.junit.jupiter:junit-jupiter-engine", version.ref = "junit-launcher" }
 jsr305 = "com.google.code.findbugs:jsr305:3.0.2"
 objenesis = "org.objenesis:objenesis:3.4"
 spock-core = { module="org.spockframework:spock-core", version.ref="spock" }
 spock-junit4 = { module="org.spockframework:spock-junit4", version.ref="spock" }
 typesafe-config = "com.typesafe:config:1.4.3"
 
 [bundles]
-spock = ["spock-core", "spock-junit4"]
+spock = ["spock-core", "spock-junit4"]

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions-snapshots/gradle-9.4.0-20251226063043+0000-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

samples-discovery/src/main/java/org/gradle/exemplar/loader/SamplesDiscovery.java

@@ -43,7 +43,7 @@ public static List<Sample> filteredExternalSamples(File rootSamplesDir, String[]
                 // FIXME: Currently the temp directory used when running samples-check has a different name.
                 // This causes Gradle project names to differ when one is not explicitly set in settings.gradle. This should be preserved.
                 final File sampleProjectDir = sampleConfigFile.getParentFile();
-                samples.add(new Sample(id, sampleProjectDir, commands));
+                samples.add(new Sample(id, sampleProjectDir, commands, sampleConfigFile));
             } catch (Exception e) {
                 samples.add(new InvalidSample(id, e));
             }

samples-discovery/src/main/java/org/gradle/exemplar/model/Sample.java

@@ -15,18 +15,28 @@
  */
 package org.gradle.exemplar.model;
 
+import javax.annotation.Nullable;
 import java.io.File;
 import java.util.List;
 
 public class Sample {
     private final String id;
     private final File projectDir;
     private final List<Command> commands;
+    private final File configFile;
 
     public Sample(String id, File projectDir, List<Command> commands) {
         this.id = id;
         this.projectDir = projectDir;
         this.commands = commands;
+        this.configFile = null;
+    }
+
+    public Sample(String id, File projectDir, List<Command> commands, File configFile) {
+        this.id = id;
+        this.projectDir = projectDir;
+        this.commands = commands;
+        this.configFile = configFile;
     }
 
     public String getId() {
@@ -40,4 +50,9 @@ public File getProjectDir() {
     public List<Command> getCommands() {
         return commands;
     }
+
+    @Nullable
+    public File getConfigFile() {
+        return configFile;
+    }
 }

samples-junit-engine/build.gradle.kts

@@ -0,0 +1,40 @@
+plugins {
+    id("exemplar.java-conventions")
+    id("jvm-test-suite")
+    id("exemplar.publishing-conventions")
+}
+
+dependencies {
+    implementation(project(":samples-check"))
+    implementation(project(":samples-discovery"))
+    implementation(libs.junit.engine)
+    implementation(libs.commons.io)
+    implementation(libs.commons.lang3)
+}
+
+testing {
+    suites {
+        register("integTest", JvmTestSuite::class) {
+            useJUnitJupiter()
+            dependencies {
+                implementation(project())
+                implementation(project(":samples-check"))
+            }
+
+            targets {
+                all {
+                    testTask.configure {
+                        mustRunAfter(tasks.named("jar"))
+                        testDefinitionDirs.from("src/test-definitions")
+                        systemProperty("exemplar.sample.modifiers", "test.TestSampleModifier")
+                        systemProperty("exemplar.output.normalizers", "test.TestOutputNormalizer")
+                    }
+                }
+            }
+        }
+    }
+}
+
+tasks.named("test", Test::class) {
+    useJUnitPlatform()
+}

samples-junit-engine/src/integTest/java/test/TestOutputNormalizer.java

@@ -0,0 +1,12 @@
+package test;
+
+import org.gradle.exemplar.executor.ExecutionMetadata;
+import org.gradle.exemplar.test.normalizer.OutputNormalizer;
+
+@SuppressWarnings("unused") // used by system property
+public class TestOutputNormalizer implements OutputNormalizer {
+    @Override
+    public String normalize(String commandOutput, ExecutionMetadata executionMetadata) {
+        return commandOutput;
+    }
+}

samples-junit-engine/src/integTest/java/test/TestSampleModifier.java

@@ -0,0 +1,12 @@
+package test;
+
+import org.gradle.exemplar.model.Sample;
+import org.gradle.exemplar.test.runner.SampleModifier;
+
+@SuppressWarnings("unused") // used by system property
+public class TestSampleModifier implements SampleModifier {
+    @Override
+    public Sample modify(Sample sampleIn) {
+        return new Sample(sampleIn.getId(), sampleIn.getProjectDir(), sampleIn.getCommands());
+    }
+}

samples-junit-engine/src/main/java/org/gradle/exemplar/ExemplarCommandDescriptor.java

@@ -0,0 +1,47 @@
+package org.gradle.exemplar;
+
+import org.gradle.exemplar.model.Command;
+import org.junit.platform.engine.UniqueId;
+import org.junit.platform.engine.support.descriptor.AbstractTestDescriptor;
+import org.junit.platform.engine.support.descriptor.DirectorySource;
+
+public final class ExemplarCommandDescriptor extends AbstractTestDescriptor {
+
+    private final Command command;
+
+    public ExemplarCommandDescriptor(ExemplarSampleDescriptor parent, Command command) {
+        super(
+            uniqueId(parent, command),
+            displayName(command),
+            DirectorySource.from(parent.getSample().getProjectDir())
+        );
+        setParent(parent);
+        this.command = command;
+    }
+
+    private static UniqueId uniqueId(ExemplarSampleDescriptor exemplarTestDescriptor, Command command) {
+        return exemplarTestDescriptor.getUniqueId().append("commandName", displayName(command));
+    }
+
+    private static String displayName(Command command) {
+        StringBuilder displayName = new StringBuilder(command.getExecutable());
+        for (String flag : command.getFlags()) {
+            displayName.append(" ");
+            displayName.append(flag);
+        }
+        for (String arg : command.getArgs()) {
+            displayName.append(" ");
+            displayName.append(arg);
+        }
+        return displayName.toString();
+    }
+
+    @Override
+    public Type getType() {
+        return Type.TEST;
+    }
+
+    public Command getCommand() {
+        return command;
+    }
+}

samples-junit-engine/src/main/java/org/gradle/exemplar/ExemplarSampleDescriptor.java

@@ -0,0 +1,52 @@
+package org.gradle.exemplar;
+
+import org.gradle.exemplar.model.Command;
+import org.gradle.exemplar.model.Sample;
+import org.junit.platform.engine.UniqueId;
+import org.junit.platform.engine.support.descriptor.AbstractTestDescriptor;
+import org.junit.platform.engine.support.descriptor.DirectorySource;
+
+import java.io.File;
+
+public final class ExemplarSampleDescriptor extends AbstractTestDescriptor {
+    private final Sample sample;
+
+    public ExemplarSampleDescriptor(UniqueId parentId, Sample sample) {
+        super(
+            parentId.append("testDefinitionFile", fileNameWithoutExtension(sample.getConfigFile()))
+                    .append("testDefinition", sample.getId()),
+            sample.getConfigFile().getParentFile().getName(),
+            DirectorySource.from(sample.getProjectDir()));
+        this.sample = sample;
+        defineTests(sample);
+    }
+
+    private void defineTests(Sample sample) {
+        for (Command command : sample.getCommands()) {
+            children.add(new ExemplarCommandDescriptor(this, command));
+        }
+    }
+
+    private static String fileNameWithoutExtension(File file) {
+        String name = file.getName();
+        int i = name.indexOf(".sample.conf");
+        if (i > 0) {
+            return name.substring(0, i);
+        }
+        return name;
+    }
+
+    @Override
+    public Type getType() {
+        return Type.CONTAINER;
+    }
+
+    public Sample getSample() {
+        return sample;
+    }
+
+    @Override
+    public String toString() {
+        return "Sample[file=" + sample.getConfigFile().getName() + ", name=" + sample.getId() + "]";
+    }
+}