Run the native formatter from the Gradle plugin on Windows

.github/workflows/ci.yml

@@ -88,7 +88,6 @@ jobs:
           JDK21_HOME: ${{ steps.jdk21.outputs.path }}
 
       # The binary itself on a file that needs formatting, a formatted one and one that does not parse.
-      # For the Windows binary this is the only check.
       - name: Smoke-test the binary
         run: |
           binary="$PWD/$(ls open-java-format-native/build/native/nativeCompile/open-java-format-* | grep -v '\.txt$')"
@@ -102,9 +101,7 @@ jobs:
           set +e; "$binary" B.java; status=$?; set -e
           test "$status" -eq 2
 
-      # The Gradle plugin does not run a native image on Windows, and its tests have never run there.
       - name: Test the plugins against the image
-        if: runner.os != 'Windows'
         run: ./gradlew -PnativeImage=true :open-java-format-jdk-bootstrap:test :gradle-open-java-format:test
         env:
           JDK21_HOME: ${{ steps.jdk21.outputs.path }}

gradle-open-java-format/build.gradle

@@ -109,8 +109,10 @@ dependencies {
 
 tasks.register("copyNativeImage", Copy.class) {
     from(configurations.formatterNativeImage)
+    // Named like the published artifact, whose extension is its artifact type: bin, and exe on Windows.
+    // The plugin's ExecutableTransform starts from that type, so a Windows binary must keep .exe.
     rename { fileName ->
-        String.format("%s.bin", fileName)
+        fileName.endsWith('.exe') ? fileName : String.format("%s.bin", fileName)
     }
     into("$buildDir/nativeImage")
 }

gradle-open-java-format/src/main/java/com/palantir/javaformat/gradle/ExecutableTransform.java

@@ -56,7 +56,9 @@ public abstract class ExecutableTransform implements TransformAction<TransformPa
     @Override
     public void transform(TransformOutputs outputs) {
         File inputFile = getInputArtifact().get().getAsFile();
-        File outputFile = outputs.file(inputFile.getName() + ".executable");
+        // The Windows binary keeps its name, so that it still ends in .exe like any Windows program.
+        String name = inputFile.getName().endsWith(".exe") ? inputFile.getName() : inputFile.getName() + ".executable";
+        File outputFile = outputs.file(name);
         try {
             Files.copy(inputFile.toPath(), outputFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
             makeFileExecutable(outputFile.toPath());
@@ -67,6 +69,10 @@ public void transform(TransformOutputs outputs) {
     }
 
     private static void makeFileExecutable(Path pathToExe) {
+        // Windows file systems have no POSIX permissions, and an .exe needs none to run.
+        if (!pathToExe.getFileSystem().supportedFileAttributeViews().contains("posix")) {
+            return;
+        }
         try {
             Set<PosixFilePermission> existingPermissions = Files.getPosixFilePermissions(pathToExe);
             Files.setPosixFilePermissions(

gradle-open-java-format/src/main/java/com/palantir/javaformat/gradle/NativeImageSupport.java

@@ -16,6 +16,7 @@
 
 package com.palantir.javaformat.gradle;
 
+import com.palantir.platform.Architecture;
 import com.palantir.platform.GradleOperatingSystem;
 import com.palantir.platform.OperatingSystem;
 import javax.inject.Inject;
@@ -37,14 +38,14 @@ public boolean isNativeImageConfigured() {
     /**
      * The platforms a native image is published for, and therefore the only ones where it can be
      * resolved. macOS is supported on both architectures: the x86-64 image used to be excluded
-     * because nobody built it, and .github/workflows/ci.yml now does. musl is still absent for the
-     * same reason — no job produces it. Windows x86-64 is built and published, but not used here yet:
-     * {@link ExecutableTransform} sets POSIX permissions, which NTFS does not have, and the tests of
-     * this plugin have never run on Windows.
+     * because nobody built it, and .github/workflows/ci.yml now does. Windows has an image for
+     * x86-64 only, and musl none: no job produces them.
      */
     private boolean isNativeImageSupported() {
         return getOs().getOperatingSystem()
-                .map(os -> os.equals(OperatingSystem.LINUX_GLIBC) || os.equals(OperatingSystem.MACOS))
+                .map(os -> os.equals(OperatingSystem.LINUX_GLIBC)
+                        || os.equals(OperatingSystem.MACOS)
+                        || (os.equals(OperatingSystem.WINDOWS) && Architecture.get() == Architecture.X86_64))
                 .get();
     }
 

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/FormatDiffTest.java

@@ -32,6 +32,7 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.List;
+import java.util.Locale;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -50,17 +51,20 @@ class FormatDiffTest {
 
     @Test
     void parsing_git_diff_output_works() throws IOException {
+        // A Windows checkout gives the fixture CRLF line endings, while git prints a diff with LF.
         String example1 = Files.readString(
-                Paths.get("src/test/resources/com/palantir/javaformat/java/FormatDiffCliTest/example1.patch"));
+                        Paths.get("src/test/resources/com/palantir/javaformat/java/FormatDiffCliTest/example1.patch"))
+                .replace("\r\n", "\n");
 
         List<String> strings = FormatDiff.parseGitDiffOutput(example1)
                 .map(FormatDiff.SingleFileDiff::toString)
                 .collect(Collectors.toList());
         assertThat(strings)
                 .containsExactly(
                         "SingleFileDiff{path=build.gradle, lineRanges=[[24..25), [29..30)]}",
-                        "SingleFileDiff{path=tracing/src/test/java/com/palantir/tracing/TracersTest.java, "
-                                + "lineRanges=[[659..660), [675..676)]}");
+                        // The path is a Path, which prints with backslashes on Windows.
+                        "SingleFileDiff{path=" + Path.of("tracing/src/test/java/com/palantir/tracing/TracersTest.java")
+                                + ", lineRanges=[[659..660), [675..676)]}");
     }
 
     @ParameterizedTest
@@ -112,7 +116,7 @@ private static Stream<FormatterService> getFormatters() throws IOException {
     }
 
     private static List<Path> getClasspath() throws IOException {
-        return Splitter.on(':')
+        return Splitter.on(File.pathSeparatorChar)
                 .trimResults()
                 .omitEmptyStrings()
                 .splitToStream(Files.readString(CLASSPATH_FILE.toPath()))
@@ -122,6 +126,10 @@ private static List<Path> getClasspath() throws IOException {
 
     private static Path javaBinPath() {
         String javaHome = Preconditions.checkNotNull(System.getProperty("java.home"), "java.home property not set");
-        return Path.of(javaHome).resolve("bin").resolve("java");
+        return Path.of(javaHome).resolve("bin").resolve("java" + (isWindows() ? ".exe" : ""));
+    }
+
+    private static boolean isWindows() {
+        return System.getProperty("os.name").toLowerCase(Locale.ROOT).startsWith("windows");
     }
 }

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/PalantirJavaFormatIdeaPluginTest.java

@@ -37,7 +37,9 @@
 
 class PalantirJavaFormatIdeaPluginTest {
 
-    private static final String NATIVE_IMAGE_FILE = new File("build/nativeImage.path").getAbsolutePath();
+    // Forward slashes: the path goes into a Groovy string, where a Windows backslash would start an escape.
+    private static final String NATIVE_IMAGE_FILE =
+            new File("build/nativeImage.path").getAbsolutePath().replace('\\', '/');
 
     private static final String NATIVE_CONFIG =
             "palantirJavaFormatNative files(file(\"" + NATIVE_IMAGE_FILE + "\").text)";

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/PalantirJavaFormatPluginTest.java

@@ -29,9 +29,12 @@
 class PalantirJavaFormatPluginTest {
 
     /** ./gradlew writeImplClasspath generates this file. */
-    private static final String CLASSPATH_FILE = new File("build/impl.classpath").getAbsolutePath();
+    // Forward slashes: the path goes into a Groovy string, where a Windows backslash would start an escape.
+    private static final String CLASSPATH_FILE =
+            new File("build/impl.classpath").getAbsolutePath().replace('\\', '/');
 
-    private static final String NATIVE_IMAGE_FILE = new File("build/nativeImage.path").getAbsolutePath();
+    private static final String NATIVE_IMAGE_FILE =
+            new File("build/nativeImage.path").getAbsolutePath().replace('\\', '/');
 
     private static final String NATIVE_CONFIG =
             "palantirJavaFormatNative files(file(\"" + NATIVE_IMAGE_FILE + "\").text)";
@@ -59,7 +62,7 @@ void formatDiff_updates_only_lines_changed_in_git_diff(String extraGradlePropert
                 .buildGradle(
                         """
                         dependencies {
-                            palantirJavaFormat files(file("%s").text.split(':'))
+                            palantirJavaFormat files(file("%s").text.split(File.pathSeparator))
                             %s
                         }
                         """,

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/PalantirJavaFormatSpotlessPluginTest.java

@@ -28,9 +28,12 @@
 class PalantirJavaFormatSpotlessPluginTest {
 
     /** ./gradlew writeImplClasspath generates this file. */
-    private static final String CLASSPATH_FILE = new File("build/impl.classpath").getAbsolutePath();
+    // Forward slashes: the path goes into a Groovy string, where a Windows backslash would start an escape.
+    private static final String CLASSPATH_FILE =
+            new File("build/impl.classpath").getAbsolutePath().replace('\\', '/');
 
-    private static final String NATIVE_IMAGE_FILE = new File("build/nativeImage.path").getAbsolutePath();
+    private static final String NATIVE_IMAGE_FILE =
+            new File("build/nativeImage.path").getAbsolutePath().replace('\\', '/');
 
     private static final String NATIVE_CONFIG =
             "palantirJavaFormatNative files(file(\"" + NATIVE_IMAGE_FILE + "\").text)";
@@ -78,7 +81,7 @@ void formats_with_spotless_when_spotless_is_applied(
                 .buildGradle(
                         """
                         dependencies {
-                            palantirJavaFormat files(file("%s").text.split(':'))
+                            palantirJavaFormat files(file("%s").text.split(File.pathSeparator))
                             %s
                         }
                         """,
@@ -87,7 +90,8 @@ palantirJavaFormat files(file("%s").text.split(':'))
 
         BuildResult result = project.succeeds("spotlessApply", "--info");
 
-        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(validJavaFile());
+        // Spotless writes the platform's line endings, CRLF on Windows.
+        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(validJavaFile());
         assertThat(result.getOutput()).contains(expectedOutput);
     }
 

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/SpotlessExcludesTest.java

@@ -29,7 +29,9 @@
 
 class SpotlessExcludesTest {
 
-    private static final String CLASSPATH_FILE = new File("build/impl.classpath").getAbsolutePath();
+    // Forward slashes: the path goes into a Groovy string, where a Windows backslash would start an escape.
+    private static final String CLASSPATH_FILE =
+            new File("build/impl.classpath").getAbsolutePath().replace('\\', '/');
 
     private static final String SOURCE_FILE =
             """
@@ -51,7 +53,7 @@ void setup() {
                 .buildGradle(
                         """
                         dependencies {
-                            palantirJavaFormat files(file("%s").text.split(':'))
+                            palantirJavaFormat files(file("%s").text.split(File.pathSeparator))
                         }
                         """,
                         CLASSPATH_FILE);

gradle-open-java-format/src/test/java/com/palantir/javaformat/gradle/SupportsCurrentSpotlessTest.java

@@ -33,7 +33,9 @@
  */
 class SupportsCurrentSpotlessTest {
 
-    private static final String CLASSPATH_FILE = new File("build/impl.classpath").getAbsolutePath();
+    // Forward slashes: the path goes into a Groovy string, where a Windows backslash would start an escape.
+    private static final String CLASSPATH_FILE =
+            new File("build/impl.classpath").getAbsolutePath().replace('\\', '/');
 
     @TempDir
     private Path projectDir;
@@ -47,7 +49,7 @@ void palantirjavaformatplugin_works_with_current_spotless() {
                 .buildGradle(
                         """
                         dependencies {
-                            palantirJavaFormat files(file("%s").text.split(':'))
+                            palantirJavaFormat files(file("%s").text.split(File.pathSeparator))
                         }
 
                         // Forces realization of the spotlessJava task, creating the spotless steps. Any

open-java-format-jdk-bootstrap/src/test/java/com/palantir/javaformat/bootstrap/FormatterServicesTest.java

@@ -26,6 +26,7 @@
 import com.palantir.javaformat.java.FormatterException;
 import com.palantir.javaformat.java.FormatterService;
 import com.palantir.javaformat.java.Replacement;
+import java.io.File;
 import java.net.URI;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -116,7 +117,7 @@ private String getTestResourceContent(String resourceName) {
 
     private static List<Path> getClasspath() {
         String classpath = System.getProperty("java.class.path");
-        return Splitter.on(':')
+        return Splitter.on(File.pathSeparatorChar)
                 .trimResults()
                 .omitEmptyStrings()
                 .splitToStream(classpath)