lintify KtLintStep.

Author: nedtwigg

lib/src/compatKtLintApi/java/com/diffplug/spotless/glue/ktlint/compat/KtLintCompatReporting.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2022 DiffPlug
+ * Copyright 2022-2024 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,11 +15,25 @@
  */
 package com.diffplug.spotless.glue.ktlint.compat;
 
-final class KtLintCompatReporting {
+public final class KtLintCompatReporting {
 
 	private KtLintCompatReporting() {}
 
 	static void report(int line, int column, String ruleId, String detail) {
-		throw new AssertionError("Error on line: " + line + ", column: " + column + "\nrule: " + ruleId + "\n" + detail);
+		throw new KtlintSpotlessException(line, ruleId, detail);
+	}
+
+	public static class KtlintSpotlessException extends RuntimeException {
+		private static final long serialVersionUID = 1L;
+
+		public final int line;
+		public final String ruleId;
+		public final String detail;
+
+		KtlintSpotlessException(int line, String ruleId, String detail) {
+			this.line = line;
+			this.ruleId = ruleId;
+			this.detail = detail;
+		}
 	}
 }

lib/src/ktlint/java/com/diffplug/spotless/glue/ktlint/KtlintFormatterFunc.java

@@ -21,6 +21,7 @@
 
 import com.diffplug.spotless.FileSignature;
 import com.diffplug.spotless.FormatterFunc;
+import com.diffplug.spotless.Lint;
 import com.diffplug.spotless.glue.ktlint.compat.*;
 
 public class KtlintFormatterFunc implements FormatterFunc.NeedsFile {
@@ -65,10 +66,14 @@ public String applyWithFile(String unix, File file) throws NoSuchFieldException,
 		if (editorConfigPath != null) {
 			absoluteEditorConfigPath = editorConfigPath.getOnlyFile().toPath();
 		}
-		return adapter.format(
-				unix,
-				file.toPath(),
-				absoluteEditorConfigPath,
-				editorConfigOverrideMap);
+		try {
+			return adapter.format(
+					unix,
+					file.toPath(),
+					absoluteEditorConfigPath,
+					editorConfigOverrideMap);
+		} catch (KtLintCompatReporting.KtlintSpotlessException e) {
+			throw Lint.atLine(e.line, e.ruleId, e.detail).shortcut();
+		}
 	}
 }

plugin-maven/src/test/java/com/diffplug/spotless/maven/kotlin/KtlintTest.java

@@ -15,8 +15,7 @@
  */
 package com.diffplug.spotless.maven.kotlin;
 
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
+import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import com.diffplug.spotless.ProcessRunner;
@@ -89,7 +88,7 @@ void testWithCustomRuleSetApply() throws Exception {
 				"</ktlint>");
 		setFile("src/main/kotlin/Main.kt").toResource("kotlin/ktlint/listScreen.dirty");
 		ProcessRunner.Result result = mavenRunner().withArguments("spotless:check").runHasError();
-		assertTrue(result.toString().contains("Composable functions that return Unit should start with an uppercase letter."));
+		Assertions.assertThat(result.toString()).contains("Composable functions that return Unit should start with an uppercase letter.");
 	}
 
 	private void checkKtlintOfficialStyle() throws Exception {

testlib/src/test/java/com/diffplug/spotless/kotlin/KtLintStepTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2023 DiffPlug
+ * Copyright 2016-2024 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,69 +29,55 @@ void works0_48_0() {
 		FormatterStep step = KtLintStep.create("0.48.0", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic-old.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: no-wildcard-imports\n" +
-						"Wildcard import");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(no-wildcard-imports) Wildcard import");
 	}
 
 	@Test
 	void works0_48_1() {
 		FormatterStep step = KtLintStep.create("0.48.1", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic-old.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: no-wildcard-imports\n" +
-						"Wildcard import");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(no-wildcard-imports) Wildcard import");
 	}
 
 	@Test
 	void works0_49_0() {
 		FormatterStep step = KtLintStep.create("0.49.0", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic-old.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: standard:no-wildcard-imports\n" +
-						"Wildcard import");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(standard:no-wildcard-imports) Wildcard import");
 	}
 
 	@Test
 	void works0_49_1() {
 		FormatterStep step = KtLintStep.create("0.49.1", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic-old.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: standard:no-wildcard-imports\n" +
-						"Wildcard import");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(standard:no-wildcard-imports) Wildcard import");
 	}
 
 	@Test
 	void works0_50_0() {
 		FormatterStep step = KtLintStep.create("0.50.0", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: standard:no-wildcard-imports\n" +
-						"Wildcard import");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(standard:no-wildcard-imports) Wildcard import");
 	}
 
 	@Test
 	void works1_0_0() {
 		FormatterStep step = KtLintStep.create("1.0.0", TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: standard:no-empty-file\n" +
-						"File 'unsolvable.dirty' should not be empty");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(standard:no-empty-file) File 'unsolvable.dirty' should not be empty");
 	}
 
 	@Test
 	void behavior() {
 		FormatterStep step = KtLintStep.create(TestProvisioner.mavenCentral());
 		StepHarnessWithFile.forStep(this, step)
 				.testResource("kotlin/ktlint/basic.dirty", "kotlin/ktlint/basic.clean")
-				.testResourceExceptionMsg("kotlin/ktlint/unsolvable.dirty").isEqualTo("Error on line: 1, column: 1\n" +
-						"rule: standard:no-empty-file\n" +
-						"File 'unsolvable.dirty' should not be empty");
+				.expectLintsOfResource("kotlin/ktlint/unsolvable.dirty").toBe("L1 ktlint(standard:no-empty-file) File 'unsolvable.dirty' should not be empty");
 	}
 
 	@Test