Fixed ignoreErrorForStep, ignoreErrorForPath, and strict error-reporting in general.

lib/src/main/java/com/diffplug/spotless/Formatter.java

@@ -212,7 +212,7 @@ public String computeLineEndings(String unix, File file) {
 	 * The input must have unix line endings, and the output
 	 * is guaranteed to also have unix line endings.
 	 */
-	public String compute(String unix, File file) throws Error {
+	public String compute(String unix, File file) {
 		for (FormatterStep step : steps) {
 			try {
 				String formatted = step.format(unix, file);

lib/src/main/java/com/diffplug/spotless/PaddedCellBulk.java

@@ -118,6 +118,7 @@ public static List<File> check(File rootDir, File diagnoseDir, Formatter formatt
 				.encoding(formatter.getEncoding())
 				.rootDir(formatter.getRootDir())
 				.steps(Collections.singletonList(paddedCellStep))
+				.exceptionPolicy(formatter.getExceptionPolicy())
 				.build();
 
 		// empty out the diagnose folder

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/JavaExtension.java

@@ -61,10 +61,10 @@ public void eclipseFormatFile(Object eclipseFormatFile) {
 		eclipseFormatFile(EclipseFormatterStep.defaultVersion(), eclipseFormatFile);
 	}
 
-	public void eclipseFormatFile(String eclipseVersion, Object... eclipseFormatFiles) {
+	public void eclipseFormatFile(String eclipseVersion, Object eclipseFormatFile) {
 		Project project = getProject();
 		addStep(EclipseFormatterStep.create(eclipseVersion,
-				project.files(eclipseFormatFiles).getFiles(),
+				project.files(eclipseFormatFile).getFiles(),
 				GradleProvisioner.fromProject(project)));
 	}
 

plugin-gradle/src/main/java/com/diffplug/gradle/spotless/SpotlessTask.java

@@ -152,6 +152,7 @@ public void performAction(IncrementalTaskInputs inputs) throws Exception {
 				.encoding(Charset.forName(encoding))
 				.rootDir(getProject().getProjectDir().toPath())
 				.steps(steps)
+				.exceptionPolicy(exceptionPolicy)
 				.build();
 		// find the outOfDate files
 		List<File> outOfDate = new ArrayList<>();

plugin-gradle/src/test/java/com/diffplug/gradle/spotless/ErrorShouldRethrow.java

@@ -15,6 +15,9 @@
  */
 package com.diffplug.gradle.spotless;
 
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -30,55 +33,109 @@
 
 /** Tests the desired behavior from https://github.com/diffplug/spotless/issues/46. */
 public class ErrorShouldRethrow extends GradleIntegrationTest {
+	private void writeBuild(String... toInsert) throws IOException {
+		List<String> lines = new ArrayList<>();
+		lines.add("plugins {");
+		lines.add("    id 'com.diffplug.gradle.spotless'");
+		lines.add("    id 'java'");
+		lines.add("}");
+		lines.add("spotless {");
+		lines.add("    format 'misc', {");
+		lines.add("        lineEndings 'UNIX'");
+		lines.add("        target file('README.md')");
+		lines.add("        custom 'no swearing', {");
+		lines.add("             if (it.toLowerCase(Locale.ROOT).contains('fubar')) {");
+		lines.add("                 throw new RuntimeException('No swearing!');");
+		lines.add("             }");
+		lines.add("        }");
+		lines.addAll(Arrays.asList(toInsert));
+		write("build.gradle", lines.toArray(new String[lines.size()]));
+	}
+
 	@Test
-	public void noSwearing() throws Exception {
-		write("build.gradle",
-				"plugins {",
-				"    id 'com.diffplug.gradle.spotless'",
-				"}",
-				"spotless {",
-				"    format 'misc', {",
-				"        target file('README.md')",
-				"        custom 'no swearing', {",
-				"             if (it.toLowerCase(Locale.ROOT).contains('fubar')) {",
-				"                 throw new AssertionError('No swearing!');",
-				"             }",
-				"        }",
-				"    }",
-				"}");
+	public void passesIfNoException() throws Exception {
+		writeBuild(
+				"    } // format",
+				"}     // spotless");
+		write("README.md", "This code is fun.");
+		runWithSuccess(":spotlessMisc");
+	}
+
+	@Test
+	public void anyExceptionShouldFail() throws Exception {
+		writeBuild(
+				"    } // format",
+				"}     // spotless");
 		write("README.md", "This code is fubar.");
-		BuildResult result = gradleRunner().withArguments("spotlessCheck").buildAndFail();
+		runWithFailure(
+				":spotlessMiscStep 'no swearing' found problem in 'README.md':",
+				"No swearing!",
+				"java.lang.RuntimeException: No swearing!");
+	}
+
+	@Test
+	public void unlessEnforceCheckIsFalse() throws Exception {
+		writeBuild(
+				"    } // format",
+				"    enforceCheck false",
+				"}     // spotless");
+		write("README.md", "This code is fubar.");
+		runWithSuccess(":compileJava UP-TO-DATE");
+	}
+
+	@Test
+	public void unlessExemptedByStep() throws Exception {
+		writeBuild(
+				"        ignoreErrorForStep 'no swearing'",
+				"    } // format",
+				"}     // spotless");
+		write("README.md", "This code is fubar.");
+		runWithSuccess(":spotlessMisc",
+				"Unable to apply step 'no swearing' to 'README.md'");
+	}
 
-		String expectedToStartWith = StringPrinter.buildStringFromLines(
+	@Test
+	public void unlessExemptedByPath() throws Exception {
+		writeBuild(
+				"        ignoreErrorForPath 'README.md'",
+				"    } // format",
+				"}     // spotless");
+		write("README.md", "This code is fubar.");
+		runWithSuccess(":spotlessMisc",
+				"Unable to apply step 'no swearing' to 'README.md'");
+	}
+
+	@Test
+	public void failsIfNeitherStepNorFileExempted() throws Exception {
+		writeBuild(
+				"        ignoreErrorForStep 'nope'",
+				"        ignoreErrorForPath 'nope'",
+				"    } // format",
+				"}     // spotless");
+		write("README.md", "This code is fubar.");
+		runWithFailure(
 				":spotlessMiscStep 'no swearing' found problem in 'README.md':",
 				"No swearing!",
-				"java.lang.AssertionError: No swearing!").trim();
+				"java.lang.RuntimeException: No swearing!");
+	}
+
+	private void runWithSuccess(String... messages) throws Exception {
+		BuildResult result = gradleRunner().withArguments("check").build();
+		assertResultAndMessages(result, TaskOutcome.SUCCESS, messages);
+	}
+
+	private void runWithFailure(String... messages) throws Exception {
+		BuildResult result = gradleRunner().withArguments("check").buildAndFail();
+		assertResultAndMessages(result, TaskOutcome.FAILED, messages);
+	}
+
+	private void assertResultAndMessages(BuildResult result, TaskOutcome outcome, String... messages) {
+		String expectedToStartWith = StringPrinter.buildStringFromLines(messages).trim();
 		int numNewlines = CharMatcher.is('\n').countIn(expectedToStartWith);
 		List<String> actualLines = Splitter.on('\n').splitToList(LineEnding.toUnix(result.getOutput()));
 		String actualStart = actualLines.subList(0, numNewlines + 1).stream().collect(Collectors.joining("\n"));
 		Assertions.assertThat(actualStart).isEqualTo(expectedToStartWith);
-		Assertions.assertThat(result.tasks(TaskOutcome.FAILED))
-				.isNotEmpty()
-				.hasSameSizeAs(result.getTasks());
-	}
-
-	@Test
-	public void noSwearingPassesIfNoSwears() throws Exception {
-		write("build.gradle",
-				"plugins {",
-				"    id 'com.diffplug.gradle.spotless'",
-				"}",
-				"spotless {",
-				"    format 'misc', {",
-				"        lineEndings 'UNIX'",
-				"        target file('README.md')",
-				"        custom 'no swearing', {",
-				"             if (it.toLowerCase(Locale.ROOT).contains('fubar')) {",
-				"                 throw new AssertionError('No swearing!');",
-				"             }",
-				"        }",
-				"    }",
-				"}");
-		write("README.md", "This code is fun.");
+		Assertions.assertThat(result.tasks(outcome).size() + result.tasks(TaskOutcome.UP_TO_DATE).size())
+				.isEqualTo(result.getTasks().size());
 	}
 }

plugin-gradle/src/test/java/com/diffplug/gradle/spotless/GoogleJavaFormatIntegrationTest.java

@@ -21,9 +21,6 @@
 import org.junit.Test;
 
 public class GoogleJavaFormatIntegrationTest extends GradleIntegrationTest {
-	// TODO: This test throws an exception because google-java-format-1.0 doesn't have
-	// RemoveUnusedImports.java (only 1.1+ does), but despite that, the test passes!
-	// Discover why this test passes and/or fix it or remove it.
 	@Test
 	public void integration() throws IOException {
 		write("build.gradle",
@@ -35,7 +32,7 @@ public void integration() throws IOException {
 				"spotless {",
 				"    java {",
 				"        target file('test.java')",
-				"        googleJavaFormat('1.1')",
+				"        googleJavaFormat('1.2')",
 				"    }",
 				"}");
 		String input = getTestResource("java/googlejavaformat/JavaCodeUnformatted.test");
@@ -49,8 +46,8 @@ public void integration() throws IOException {
 		checkRunsThenUpToDate();
 
 		replace("build.gradle",
-				"googleJavaFormat('1.1')",
-				"googleJavaFormat('1.0')");
+				"googleJavaFormat('1.2')",
+				"googleJavaFormat('1.3')");
 		checkRunsThenUpToDate();
 	}
 }

spotlessSelf.gradle

@@ -7,7 +7,10 @@ plugins {
 repositories { mavenCentral() }
 spotless {
 	java {
-		target '**/*.java'
+		target fileTree('.') {
+			include '**/*.java'
+			exclude '_ext/*/build/**'
+		}
 
 		custom 'noInternalDeps', {
 			if (it.contains('import org.gradle.internal.')) {

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

@@ -103,9 +103,13 @@ public void invalidPropertyFiles() throws IOException {
 	}
 
 	@Test
-	public void nonExisitingFile() throws IOException {
+	public void nonExistingFile() throws IOException {
 		boolean exceptionCaught = false;
 		String filePath = "does/not/exist.properties";
+		boolean isWin = LineEnding.PLATFORM_NATIVE.str().equals(LineEnding.WINDOWS.str());
+		if (isWin) {
+			filePath = filePath.replace('/', '\\');
+		}
 		try {
 			FormatterProperties.from(new File(filePath));
 		} catch (IllegalArgumentException ex) {