Keep the files' line endings in every TestKit build with Spotless

Spotless checks for, and writes, the platform's line endings by
default, CRLF on Windows, while the tests write their files with LF.
On Windows a check then reports the line endings instead of the
formatting: a_file_the_formatter_cannot_parse_is_still_a_lint_of_that_file
failed there, as the up-to-date test did before d289fcd set
lineEndings to PRESERVE in its own build.

GradleTestProject now sets lineEndings to PRESERVE in every project of
a generated build that applies Spotless, so no test has to remember
it. Spotless then writes LF back, and the tests compare the files they
leave exactly instead of ignoring line endings.

Author: abashev

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

@@ -67,10 +67,10 @@ final class BuildCacheTest {
     void spotlessJava_is_up_to_date_when_the_source_is_written_again_unchanged() {
         var project = project(projectDir);
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
 
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.UP_TO_DATE);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -79,7 +79,7 @@ void spotlessJava_runs_again_when_the_source_changes() {
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
 
         assertThat(spotlessApply(project, OTHER_UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(OTHER_FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(OTHER_FORMATTED);
     }
 
     @Test
@@ -89,7 +89,7 @@ void spotlessJava_comes_from_the_cache_when_the_source_changes_back() {
         assertThat(spotlessApply(project, OTHER_UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
 
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.FROM_CACHE);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -100,7 +100,7 @@ void spotlessJava_comes_from_the_cache_after_the_build_directory_is_deleted() {
         project.delete("build");
 
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.FROM_CACHE);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -111,7 +111,7 @@ void spotlessJava_comes_from_the_cache_in_another_directory() {
         var moved = project(otherProjectDir);
 
         assertThat(spotlessApply(moved, UNFORMATTED)).isEqualTo(TaskOutcome.FROM_CACHE);
-        assertThat(moved.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(moved.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -123,7 +123,7 @@ void spotlessJava_runs_again_when_the_build_declares_a_formatter() throws IOExce
         project.writeFile("formatter.classpath", formatterClasspath()).delete("build");
 
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -140,7 +140,7 @@ void spotlessJava_runs_again_when_the_declared_jars_change() throws IOException,
                 .delete("build");
 
         assertThat(spotlessApply(project, UNFORMATTED)).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     /** The formatter inside the plugin, unless the test writes formatter.classpath, which the build then declares. */

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

@@ -79,8 +79,7 @@ void spotlessApply_formats_from_a_reused_entry() throws IOException {
             project.writeFile(MAIN_JAVA, UNFORMATTED);
 
             assertThat(project.succeeds("spotlessApply").getOutput()).contains(entry);
-            // Spotless writes the platform's line endings, CRLF on Windows.
-            assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+            assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
         }
     }
 
@@ -126,7 +125,7 @@ void spotlessApply_reuses_the_entry_after_the_extracted_formatter_is_deleted() t
         var reused = project.succeeds("spotlessApply");
 
         assertThat(reused.getOutput()).contains(REUSED);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test
@@ -146,11 +145,11 @@ palantirJavaFormat files(file("formatter.classpath").text.split(File.pathSeparat
         // spotlessApply of the same source each time, and the file it leaves: a step that changes nothing is up to
         // date just as well, and passes a spotlessCheck of a formatted file.
         assertThat(spotlessJava(spotlessApply(project))).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
         var unchanged = spotlessApply(project);
         assertThat(unchanged.getOutput()).contains(REUSED);
         assertThat(spotlessJava(unchanged)).isEqualTo(TaskOutcome.UP_TO_DATE);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
 
         // Spotless signs the jars by name, size and content, as another formatter version changes them. The extra jar
         // is JUnit's, not one written into projectDir: the daemon keeps the formatter's jars open after the build, and
@@ -160,7 +159,7 @@ palantirJavaFormat files(file("formatter.classpath").text.split(File.pathSeparat
         project.writeFile("formatter.classpath", jars + File.pathSeparator + extraJar);
 
         assertThat(spotlessJava(spotlessApply(project))).isEqualTo(TaskOutcome.SUCCESS);
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     /** spotlessApply of the unformatted source, written again: only its time changes. */

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

@@ -177,8 +177,7 @@ private GradleTestProject project() {
 
     private static void assertFormatted(GradleTestProject project, String... files) {
         for (var file : files) {
-            // Spotless writes the platform's line endings, CRLF on Windows.
-            assertThat(project.readFile(file)).as(file).isEqualToNormalizingNewlines(FORMATTED);
+            assertThat(project.readFile(file)).as(file).isEqualTo(FORMATTED);
         }
     }
 

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

@@ -84,8 +84,7 @@ void formats_with_spotless_when_spotless_is_applied(
 
         BuildResult result = project.succeeds("spotlessApply", "--info");
 
-        // Spotless writes the platform's line endings, CRLF on Windows.
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(validJavaFile());
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(validJavaFile());
         assertThat(result.getOutput()).contains(expectedOutput);
     }
 

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

@@ -89,8 +89,7 @@ void format_ignores_excluded_directories(String srcDir) {
         assertThat(result.task(":spotlessJava")).isNotNull().extracting(task -> task.getOutcome())
                 .isEqualTo(TaskOutcome.SUCCESS);
         assertThat(project.readFile(srcDir + "/test/Test.java")).isEqualTo(SOURCE_FILE);
-        // Spotless writes the platform's line endings, CRLF on Windows.
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED_MAIN);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED_MAIN);
     }
 
     @ParameterizedTest

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

@@ -75,8 +75,7 @@ void spotlessApply_formats_once_the_gradle_jvm_exports_javac() {
         var result = project.succeeds("spotlessApply");
 
         assertThat(spotlessJava(result)).isEqualTo(TaskOutcome.SUCCESS);
-        // Spotless writes the platform's line endings, CRLF on Windows.
-        assertThat(project.readFile(MAIN_JAVA)).isEqualToNormalizingNewlines(FORMATTED);
+        assertThat(project.readFile(MAIN_JAVA)).isEqualTo(FORMATTED);
     }
 
     @Test

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

@@ -182,8 +182,7 @@ private static void commitThenChange(GradleTestProject project, String... files)
 
     private static void assertFormatted(GradleTestProject project, String... files) {
         for (var file : files) {
-            // Spotless writes the platform's line endings, CRLF on Windows.
-            assertThat(project.readFile(file)).as(file).isEqualToNormalizingNewlines(FORMATTED);
+            assertThat(project.readFile(file)).as(file).isEqualTo(FORMATTED);
         }
     }
 

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

@@ -245,6 +245,19 @@ private void write() {
         if (repositories) {
             script.append("repositories {\n    mavenCentral()\n}\n\n");
         }
+        // Spotless checks for, and writes, the platform's line endings by default, CRLF on Windows, while the tests
+        // write their files with LF: a check would report the line endings, not the formatting. PRESERVE keeps the
+        // file's own, wherever a test applies Spotless.
+        script.append("""
+            allprojects {
+                plugins.withId('com.diffplug.spotless') {
+                    spotless {
+                        lineEndings = 'PRESERVE'
+                    }
+                }
+            }
+
+            """);
         script.append(buildGradle);
 
         StringBuilder settings = new StringBuilder("rootProject.name = 'test-project'\n");