GH-1438 - Support to skip all tests if no code changes are detected.

Original pull request: GH-1484.

Signed-off-by: Valentin Bossi <[email protected]>

Author: ValentinBossi

spring-modulith-integration-test/src/test/java/org/springframework/modulith/junit/TestExecutionConditionUnitTests.java

@@ -22,6 +22,7 @@
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ConditionEvaluationResult;
+import org.springframework.modulith.junit.Changes.OnNoChange;
 import org.springframework.modulith.junit.TestExecutionCondition.ConditionContext;
 import org.springframework.modulith.junit.diff.ModifiedFile;
 
@@ -89,7 +90,7 @@ private void assertEnabled(Class<?> type, boolean expected, String... files) {
 
 	private void assertEnabled(Class<?> type, boolean expected, Stream<ModifiedFile> files) {
 
-		assertThat(condition.evaluate(new ConditionContext(type, Changes.of(files))))
+		assertThat(condition.evaluate(new ConditionContext(type, Changes.of(files, OnNoChange.DEFAULT))))
 				.extracting(ConditionEvaluationResult::isDisabled)
 				.isNotEqualTo(expected);
 	}

spring-modulith-junit/src/main/java/org/springframework/modulith/junit/Changes.java

@@ -16,6 +16,7 @@
 package org.springframework.modulith.junit;
 
 import static java.util.stream.Collectors.*;
+import static org.springframework.modulith.junit.Changes.OnNoChange.EXECUTE_NO_TESTS;
 
 import java.util.Collection;
 import java.util.Collections;
@@ -42,20 +43,23 @@
  */
 public class Changes implements Iterable<Change> {
 
-	public static final Changes NONE = new Changes(Collections.emptySet());
+	public static final Changes NONE = new Changes(Collections.emptySet(), OnNoChange.DEFAULT);
 
 	private final Collection<Change> changes;
+	private final OnNoChange onNoChangeConfig;
 
 	/**
 	 * Creates a new {@link Changes} instance from the given {@link Change}s.
 	 *
 	 * @param changes must not be {@literal null}.
 	 */
-	private Changes(Collection<Change> changes) {
+	private Changes(Collection<Change> changes, OnNoChange config) {
 
 		Assert.notNull(changes, "Changes must not be null!");
+		Assert.notNull(config, "OnNoChange must not be null!");
 
 		this.changes = changes;
+		this.onNoChangeConfig = config;
 	}
 
 	/**
@@ -64,11 +68,11 @@ private Changes(Collection<Change> changes) {
 	 * @param files must not be {@literal null}.
 	 * @return will never be {@literal null}.
 	 */
-	static Changes of(Stream<ModifiedFile> files) {
+	static Changes of(Stream<ModifiedFile> files, OnNoChange config) {
 
 		Assert.notNull(files, "Modified files must not be null!");
 
-		return files.map(Change::of).collect(collectingAndThen(toSet(), Changes::new));
+		return files.map(Change::of).collect(collectingAndThen(toSet(), changes ->  new Changes(changes, config)));
 	}
 
 	/**
@@ -88,6 +92,10 @@ boolean hasClassChanges() {
 		return !getChangedClasses().isEmpty();
 	}
 
+	boolean skipTestsOnNoChanges() {
+		return onNoChangeConfig == EXECUTE_NO_TESTS;
+	}
+
 	boolean contains(Class<?> type) {
 		return changes.stream().anyMatch(it -> it.hasOrigin(type.getName()));
 	}
@@ -328,4 +336,20 @@ public final String toString() {
 			}
 		}
 	}
+
+	enum OnNoChange {
+		EXECUTE_ALL_TESTS("execute-all"),
+		EXECUTE_NO_TESTS("execute-none");
+
+		final String value;
+		static final OnNoChange DEFAULT = OnNoChange.EXECUTE_ALL_TESTS;
+
+		OnNoChange(String value) {
+			this.value = value;
+		}
+
+		public static OnNoChange propertyConfig(String value) {
+			return EXECUTE_NO_TESTS.value.equals(value) ? EXECUTE_NO_TESTS : DEFAULT;
+		}
+	}
 }

spring-modulith-junit/src/main/java/org/springframework/modulith/junit/ChangesFactory.java

@@ -18,6 +18,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.core.env.Environment;
+import org.springframework.modulith.junit.Changes.OnNoChange;
 import org.springframework.modulith.junit.diff.FileModificationDetector;
 import org.springframework.util.Assert;
 
@@ -45,9 +46,11 @@ static Changes getChanges(Environment environment) {
 			return Changes.NONE;
 		}
 
+		var onNoChangesConfig = OnNoChange.propertyConfig(environment.getProperty("spring.modulith.test.on-no-changes"));
+
 		// Determine detector
 		var detector = FileModificationDetector.getDetector(environment);
-		var result = Changes.of(detector.getModifiedFiles());
+		var result = Changes.of(detector.getModifiedFiles(), onNoChangesConfig);
 
 		if (log.isInfoEnabled()) {
 

spring-modulith-junit/src/main/java/org/springframework/modulith/junit/TestExecutionCondition.java

@@ -59,7 +59,9 @@ ConditionEvaluationResult evaluate(ConditionContext context) {
 		}
 
 		if (!changes.hasClassChanges()) {
-			return enabled("No source file changes detected.");
+			return changes.skipTestsOnNoChanges()
+				? disabled("No source file changes detected — tests skipped due to configuration \"on-no-changes=execute-none\".")
+				: enabled("No source file changes detected — running full test suite due to default configuration.");
 		}
 
 		var changedClasses = changes.getChangedClasses();

spring-modulith-junit/src/main/resources/META-INF/spring-configuration-metadata.json

@@ -15,9 +15,27 @@
 			"name": "spring.modulith.test.reference-commit",
 			"type": "java.lang.String",
 			"description": "The hash of the commit to track back changes to. Usually set in a CI environment."
+		},
+		{
+			"name": "spring.modulith.test.on-no-changes",
+			"type": "java.lang.String",
+			"description": "Whether all tests or no tests should be executed when no class changes are detected."
 		}
 	],
 	"hints": [
+		{
+			"name": "spring.modulith.test.on-no-changes",
+			"values": [				
+				{
+					"value": "execute-all",
+					"description" : "Executes all tests."
+				},
+				{
+					"value": "execute-none",
+					"description" : "Executes no tests."
+				}
+			]
+		},
 		{
 			"name": "spring.modulith.test.file-modification-detector",
 			"values": [				

spring-modulith-junit/src/test/java/org/springframework/modulith/junit/ChangesFactoryUnitTests.java

@@ -23,6 +23,7 @@
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.MapPropertySource;
 import org.springframework.core.env.StandardEnvironment;
+import org.springframework.modulith.junit.Changes.OnNoChange;
 
 /**
  * Unit tests for {@link ChangesFactory}.
@@ -37,6 +38,39 @@ void returnsNoChangesIfDisabledByProperty() {
 		var environment = getEnvironment(Map.of("spring.modulith.test.skip-optimizations", "true"));
 
 		assertThat(ChangesFactory.getChanges(environment)).isEqualTo(Changes.NONE);
+		assertThat(ChangesFactory.getChanges(environment).skipTestsOnNoChanges()).isFalse();
+	}
+
+	@Test // GH-1438
+	void skipTestsOnNoChangesSetByProperty() {
+
+		var environment = getEnvironment(Map.of("spring.modulith.test.on-no-changes", OnNoChange.EXECUTE_NO_TESTS.value));
+
+		assertThat(ChangesFactory.getChanges(environment).hasClassChanges()).isFalse();
+		assertThat(ChangesFactory.getChanges(environment).skipTestsOnNoChanges()).isTrue();
+	}
+
+	@Test // GH-1438
+	void executeTestsOnNoChangesSetByProperty() {
+
+		var environment = getEnvironment(Map.of("spring.modulith.test.on-no-changes", OnNoChange.DEFAULT.value));
+
+		assertThat(ChangesFactory.getChanges(environment).hasClassChanges()).isFalse();
+		assertThat(ChangesFactory.getChanges(environment).skipTestsOnNoChanges()).isFalse();
+	}
+
+	@Test // GH-1438
+	void executeTestsByDefaultOrInvalidValue() {
+
+		var environment = getEnvironment(Map.of("spring.modulith.test.on-no-changes", "1"));
+
+		assertThat(ChangesFactory.getChanges(environment).hasClassChanges()).isFalse();
+		assertThat(ChangesFactory.getChanges(environment).skipTestsOnNoChanges()).isFalse();
+
+		environment = getEnvironment(Map.of());
+
+		assertThat(ChangesFactory.getChanges(environment).hasClassChanges()).isFalse();
+		assertThat(ChangesFactory.getChanges(environment).skipTestsOnNoChanges()).isFalse();
 	}
 
 	private Environment getEnvironment(Map<String, Object> properties) {

spring-modulith-junit/src/test/java/org/springframework/modulith/junit/ChangesUnitTests.java

@@ -22,11 +22,13 @@
 import org.junit.jupiter.api.DynamicTest;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.TestFactory;
+import org.springframework.core.env.StandardEnvironment;
 import org.springframework.modulith.junit.Changes.Change.JavaSourceChange;
 import org.springframework.modulith.junit.Changes.Change.JavaTestSourceChange;
 import org.springframework.modulith.junit.Changes.Change.KotlinSourceChange;
 import org.springframework.modulith.junit.Changes.Change.KotlinTestSourceChange;
 import org.springframework.modulith.junit.Changes.Change.OtherFileChange;
+import org.springframework.modulith.junit.Changes.OnNoChange;
 import org.springframework.modulith.junit.diff.ModifiedFile;
 
 /**
@@ -81,7 +83,7 @@ void shouldInterpredModifiedFilePathsCorrectly() {
 				.map(ModifiedFile::new);
 
 		// when
-		var result = Changes.of(modifiedFilePaths);
+		var result = Changes.of(modifiedFilePaths, OnNoChange.DEFAULT);
 
 		// then
 		assertThat(result.hasClasspathResourceChange()).isTrue();

spring-modulith-junit/src/test/java/org/springframework/modulith/junit/TestExecutionConditionUnitTests.java

@@ -21,6 +21,7 @@
 
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.modulith.junit.Changes.OnNoChange;
 import org.springframework.modulith.junit.diff.ModifiedFile;
 
 /**
@@ -33,12 +34,21 @@ class TestExecutionConditionUnitTests {
 	@Test // GH-1391
 	void fallsBackToEnabledTestIfMultipleMainClassesFound() {
 
-		var changes = Changes.of(Stream.of(new ModifiedFile("Foo.java")));
+		var changes = Changes.of(Stream.of(new ModifiedFile("Foo.java")), OnNoChange.DEFAULT);
 		var ctx = new TestExecutionCondition.ConditionContext(getClass(), changes);
 
 		assertThat(new TestExecutionCondition().evaluate(ctx).isDisabled()).isFalse();
 	}
 
+	@Test // GH-1438
+	void disablesForNoClassChangesWithPropertyConfiguration() {
+
+		var changes = Changes.of(Stream.of( new ModifiedFile("README.md")), OnNoChange.propertyConfig(OnNoChange.EXECUTE_NO_TESTS.value));
+		var ctx = new TestExecutionCondition.ConditionContext(getClass(), changes);
+
+		assertThat(new TestExecutionCondition().evaluate(ctx).isDisabled()).isTrue();
+	}
+
 	@SpringBootConfiguration
 	static class First {}