spotlessApply no longer clobbers file permissions (pr #656, fixes #654)

plugin-gradle/CHANGES.md

@@ -3,6 +3,7 @@
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `3.27.0`).
 
 ## [Unreleased]
+* Depending on the file system, executing `gradle spotlessApply` might change permission on the changed files from `644` to `755`; fixes ([#656](https://github.com/diffplug/spotless/pull/656))
 * Bump default ktfmt from 0.15 to 0.16, and remove duplicated logic for the --dropbox-style option ([#642](https://github.com/diffplug/spotless/pull/648))
 
 ## [5.1.0] - 2020-07-13

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

@@ -68,7 +68,7 @@ public void visitFile(FileVisitDetails fileVisitDetails) {
 					File originalSource = new File(getProject().getProjectDir(), path);
 					try {
 						getLogger().debug("Copying " + fileVisitDetails.getFile() + " to " + originalSource);
-						Files.copy(fileVisitDetails.getFile().toPath(), originalSource.toPath(), StandardCopyOption.REPLACE_EXISTING);
+						Files.copy(fileVisitDetails.getFile().toPath(), originalSource.toPath(), StandardCopyOption.REPLACE_EXISTING, StandardCopyOption.COPY_ATTRIBUTES);
 					} catch (IOException e) {
 						throw new RuntimeException(e);
 					}

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

@@ -19,6 +19,7 @@
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
 import java.util.Comparator;
 
 import org.gradle.api.GradleException;
@@ -80,6 +81,8 @@ private void processInputFile(Formatter formatter, File input) throws IOExceptio
 				throw new IllegalStateException("Every file has a parent folder.");
 			}
 			Files.createDirectories(parentDir);
+			// Need to copy the original file to the tmp location just to remember the file attributes
+			Files.copy(input.toPath(), output.toPath(), StandardCopyOption.REPLACE_EXISTING, StandardCopyOption.COPY_ATTRIBUTES);
 			dirtyState.writeCanonicalTo(output);
 		}
 	}

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

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2020 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.gradle.spotless;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.attribute.PosixFilePermissions;
+
+import org.assertj.core.api.AbstractStringAssert;
+import org.assertj.core.api.Assertions;
+import org.junit.Test;
+
+import com.diffplug.spotless.FileSignature;
+
+public class FilePermissionsTest extends GradleIntegrationHarness {
+	@Test
+	public void spotlessApplyShouldPreservePermissions() throws IOException {
+		if (FileSignature.machineIsWin()) {
+			// need unix filesystem
+			return;
+		}
+		setFile("build.gradle").toLines(
+				"buildscript { repositories { mavenCentral() } }",
+				"plugins {",
+				"    id 'com.diffplug.spotless'",
+				"}",
+				"",
+				"spotless {",
+				"    java {",
+				"        target file('test.java')",
+				"        googleJavaFormat('1.2')",
+				"    }",
+				"}");
+		setFile("test.java").toResource("java/googlejavaformat/JavaCodeUnformatted.test");
+
+		Path path = rootFolder().toPath().resolve("test.java");
+		Files.setPosixFilePermissions(path, PosixFilePermissions.fromString("rwxr--r--"));
+		assertPermissions(path).isEqualTo("rwxr--r--");
+
+		gradleRunner().withArguments("spotlessApply").build();
+		assertFile("test.java").sameAsResource("java/googlejavaformat/JavaCodeFormatted.test");
+		assertPermissions(path).isEqualTo("rwxr--r--");
+	}
+
+	private AbstractStringAssert<?> assertPermissions(Path path) throws IOException {
+		return Assertions.assertThat(PosixFilePermissions.toString(Files.getPosixFilePermissions(path)));
+	}
+}