[prone] Apply UnnecessaryLambda

Author: Vincent Potucek

gradle/error-prone.gradle

@@ -13,21 +13,10 @@ tasks.withType(JavaCompile).configureEach {
 				'FormatStringConcatenation',
 				'FunctionalInterfaceMethodChanged',
 				'JavaxInjectOnAbstractMethod',
+				'MissingSummary',
 				'OverridesJavaxInjectableMethod',
 				'ReturnValueIgnored',
 				'Slf4jLogStatement',
-				'MissingSummary',
-				// patchable
-				'LexicographicalAnnotationAttributeListing',
-				'LexicographicalAnnotationListing',
-				'NonStaticImport',
-				'Slf4jLoggerDeclaration', // logger -> log
-				'StaticImport',
-				// critical, finds lots of bugs... unused configs and stuff.
-				'Unused',
-				'UnusedMethod',
-				'UnusedParameters',
-				'UnusedVariable',
 				)
 		error(
 				'AmbiguousJsonCreator',
@@ -41,6 +30,7 @@ tasks.withType(JavaCompile).configureEach {
 				'ExplicitArgumentEnumeration',
 				'ExplicitEnumOrdering',
 				'IdentityConversion',
+				'UnnecessaryLambda',
 				'ImmutablesSortedSetComparator',
 				'IsInstanceLambdaUsage',
 				'MockitoMockClassReference',
@@ -53,10 +43,9 @@ tasks.withType(JavaCompile).configureEach {
 				'StringJoin',
 				'StringJoining',
 				)
-		// fixme bug: this only happens when the file is dirty!
-		// up2date checking (caching) must consider file changes, as file is currently corrupt!
-		// fix SelfTest.java:L22 ForbidGradleInternal(import org.gradle.api.internal.project.ProjectInternal;)
-		errorproneArgs.add('-XepExcludedPaths:.*/SelfTest.java')
+		// bug: this only happens when the file is dirty.
+		// might be an up2date (caching) issue, as file is currently in corrupt state.
+		errorproneArgs.add('-XepExcludedPaths:.*/SelfTest.java') // fix: SelfTest.java:L22 ForbidGradleInternal(import org.gradle.api.internal.project.ProjectInternal;)
 		if (!getenv().containsKey('CI') && getenv('IN_PLACE')?.toBoolean()) {
 			errorproneArgs.addAll(
 					'-XepPatchLocation:IN_PLACE',
@@ -65,6 +54,7 @@ tasks.withType(JavaCompile).configureEach {
 					'ArrayEquals,' +
 					'AssertJNullnessAssertion,' +
 					'AutowiredConstructor,' +
+					'UnnecessaryLambda,' +
 					'CanonicalAnnotationSyntax,' +
 					'CollectorMutability,' +
 					'ConstantNaming,' +
@@ -85,8 +75,7 @@ tasks.withType(JavaCompile).configureEach {
 					'SelfAssignment,' +
 					'Slf4jLogStatement,' +
 					'StringJoin,' +
-					'StringJoining,' +
-					'TimeZoneUsage,'
+					'StringJoining,'
 					)
 		}
 	}

lib-extra/src/test/java/com/diffplug/spotless/extra/GitAttributesTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -85,7 +85,7 @@ void policyTest() {
 		setFile(".gitattributes").toContent(StringPrinter.buildStringFromLines(
 				"* eol=lf",
 				"*.MF eol=crlf"));
-		LineEnding.Policy policy = LineEnding.GIT_ATTRIBUTES.createPolicy(rootFolder(), () -> testFiles());
+		LineEnding.Policy policy = LineEnding.GIT_ATTRIBUTES.createPolicy(rootFolder(), this::testFiles);
 		Assertions.assertThat(policy.getEndingFor(newFile("someFile"))).isEqualTo("\n");
 		Assertions.assertThat(policy.getEndingFor(newFile("subfolder/someFile"))).isEqualTo("\n");
 		Assertions.assertThat(policy.getEndingFor(newFile("MANIFEST.MF"))).isEqualTo("\r\n");
@@ -100,7 +100,7 @@ void policyDefaultLineEndingTest() throws GitAPIException {
 				"[core]",
 				"autocrlf=true",
 				"eol=lf"));
-		LineEnding.Policy policy = LineEnding.GIT_ATTRIBUTES.createPolicy(rootFolder(), () -> testFiles());
+		LineEnding.Policy policy = LineEnding.GIT_ATTRIBUTES.createPolicy(rootFolder(), this::testFiles);
 		Assertions.assertThat(policy.getEndingFor(newFile("someFile"))).isEqualTo("\r\n");
 	}
 

plugin-maven/src/main/java/com/diffplug/spotless/maven/ArtifactResolver.java

@@ -66,7 +66,7 @@ public Set<File> resolve(boolean withTransitives, Collection<String> mavenCoordi
 			excludeTransitive.add(EXCLUDE_ALL_TRANSITIVES);
 		}
 		List<Dependency> dependencies = mavenCoordinates.stream()
-				.map(coordinateString -> new DefaultArtifact(coordinateString))
+				.map(DefaultArtifact::new)
 				.map(artifact -> new Dependency(artifact, null, null, excludeTransitive))
 				.collect(toList());
 		CollectRequest collectRequest = new CollectRequest(dependencies, null, repositories);

testlib/src/main/java/com/diffplug/spotless/TestProvisioner.java

@@ -143,19 +143,16 @@ public static Provisioner mavenCentral() {
 		return MAVEN_CENTRAL.get();
 	}
 
-	private static final Supplier<Provisioner> MAVEN_CENTRAL = Suppliers.memoize(() -> caching("mavenCentral", () -> createWithRepositories(repo -> repo.mavenCentral())));
+	private static final Supplier<Provisioner> MAVEN_CENTRAL = Suppliers.memoize(() -> caching("mavenCentral", () -> createWithRepositories(RepositoryHandler::mavenCentral)));
 
 	/** Creates a Provisioner for the local maven repo for development purpose. */
 	public static Provisioner mavenLocal() {
-		return MAVEN_LOCAL.get();
+		return createWithRepositories(RepositoryHandler::mavenLocal);
 	}
 
-	private static final Supplier<Provisioner> MAVEN_LOCAL = () -> createWithRepositories(repo -> repo.mavenLocal());
-
 	/** Creates a Provisioner for the Sonatype snapshots maven repo for development purpose. */
 	public static Provisioner snapshots() {
-		return SNAPSHOTS.get();
+		return createWithRepositories(repo -> repo.maven(setup -> setup.setUrl("https://oss.sonatype.org/content/repositories/snapshots")));
 	}
 
-	private static final Supplier<Provisioner> SNAPSHOTS = () -> createWithRepositories(repo -> repo.maven(setup -> setup.setUrl("https://oss.sonatype.org/content/repositories/snapshots")));
 }

testlib/src/test/java/com/diffplug/spotless/FormatterPropertiesTest.java

@@ -196,7 +196,7 @@ public FormatterSettingsAssert(FormatterProperties actual) {
 
 		/** Check that the values form all valid files are part of the settings properties. */
 		public FormatterSettingsAssert containsSpecificValuesOf(Collection<File> files) {
-			files.forEach(file -> containsSpecificValuesOf(file));
+			files.forEach(this::containsSpecificValuesOf);
 			return this;
 		}