Polish 'Detect and preserve line separators'

See gh-340

Author: philwebb

Diff for: spring-javaformat-gradle/spring-javaformat-gradle-plugin/src/test/java/io/spring/javaformat/gradle/CheckTaskTests.java

@@ -18,12 +18,11 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.nio.file.StandardCopyOption;
 import java.nio.file.StandardOpenOption;
 import java.util.Arrays;
-import java.util.List;
 import java.util.stream.Stream;
 
 import org.gradle.testkit.runner.BuildResult;
@@ -68,12 +67,12 @@ void whenFirstInvocationSucceedsThenSecondInvocationIsUpToDate() throws IOExcept
 
 	@Test
 	void whenFirstInvocationSucceedsAndSourceIsModifiedThenSecondInvocationSucceeds() throws IOException {
-		copyFolder(new File("src/test/resources/check-ok").toPath(), this.temp.toPath());
+		copyNormalizedFolder(new File("src/test/resources/check-ok").toPath(), this.temp.toPath());
 		GradleBuild gradleBuild = this.gradleBuild.source(this.temp);
 		BuildResult result = gradleBuild.build("check");
 		assertThat(result.task(":checkFormatMain").getOutcome()).isEqualTo(TaskOutcome.SUCCESS);
-		appendToFileNormalizingNewlines(new File(this.temp, "src/main/java/simple/Simple.java").toPath(),
-				"// A change to the file");
+		Files.write(new File(this.temp, "src/main/java/simple/Simple.java").toPath(),
+				"// A change to the file\n".getBytes(StandardCharsets.UTF_8), StandardOpenOption.APPEND);
 		result = gradleBuild.build("--debug", "check");
 		assertThat(result.task(":checkFormatMain").getOutcome()).isEqualTo(TaskOutcome.SUCCESS);
 	}
@@ -129,14 +128,17 @@ void whenFirstInvocationFailsThenSecondInvocationFails() throws IOException {
 		assertThat(result.task(":checkFormatMain").getOutcome()).isEqualTo(TaskOutcome.FAILED);
 	}
 
-	private void copyFolder(Path source, Path target) throws IOException {
+	private void copyNormalizedFolder(Path source, Path target) throws IOException {
 		try (Stream<Path> stream = Files.walk(source)) {
 			stream.forEach((child) -> {
 				try {
 					Path relative = source.relativize(child);
 					Path destination = target.resolve(relative);
-					if (!destination.toFile().isDirectory()) {
-						Files.copy(child, destination, StandardCopyOption.REPLACE_EXISTING);
+					if (!Files.isDirectory(child)) {
+						String content = new String(Files.readAllBytes(child), StandardCharsets.UTF_8);
+						String normalized = content.replace("\n\r", "\n").replace('\r', '\n');
+						Files.createDirectories(destination.getParent());
+						Files.write(destination, normalized.getBytes(StandardCharsets.UTF_8));
 					}
 				}
 				catch (Exception ex) {
@@ -146,14 +148,4 @@ private void copyFolder(Path source, Path target) throws IOException {
 		}
 	}
 
-	/**
-	 * Uses a read/modify/truncate approach to append a line to a file.
-	 * This avoids issues where the standard append option results in mixed line-endings.
-	 */
-	private void appendToFileNormalizingNewlines(Path sourceFilePath, String lineToAppend) throws IOException {
-		List<String> lines = Files.readAllLines(sourceFilePath);
-		lines.add(lineToAppend);
-		Files.write(sourceFilePath, lines, StandardOpenOption.TRUNCATE_EXISTING);
-	}
-
 }

Diff for: spring-javaformat-maven/spring-javaformat-maven-plugin/src/it/.gitattributes

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2021 the original author or authors.
+ * Copyright 2017-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,16 +30,14 @@
  */
 public class VerifyApply {
 
-	private static final String LF = "\n";
-
 	private static final String JAVA_FILE = "src/main/java/simple/Simple.java";
 
 	public void verify(File base) throws IOException {
-		verify(base, LF);
+		verify(base, null);
 	}
 
 	public void verify(File base, boolean spaces) throws IOException {
-		verify(base, LF, spaces);
+		verify(base, null, spaces);
 	}
 
 	public void verify(File base, String lineSeparator) throws IOException {
@@ -48,16 +46,14 @@ public void verify(File base, String lineSeparator) throws IOException {
 
 	public void verify(File base, String lineSeparator, boolean spaces) throws IOException {
 		String formated = new String(Files.readAllBytes(base.toPath().resolve(JAVA_FILE)), StandardCharsets.UTF_8);
+		if (lineSeparator == null) {
+			formated = formated.replace("\r\n", "\n").replace('\r', '\n');
+			lineSeparator = "\n";
+		}
 		String indent = (!spaces) ? "	" : "    ";
 		assertThat(formated).contains("Simple." + lineSeparator + " *" + lineSeparator + " * @author")
 			.contains("public class Simple {")
 			.contains(indent + "public static void main");
 	}
 
-	public static void main(String[] args) throws IOException {
-		new VerifyApply().verify(new File(
-				"/Users/pwebb/projects/spring-javaformat/code/spring-javaformat-maven/spring-javaformat-maven-plugin/target/it/apply-line-separator"),
-				"\r");
-	}
-
 }

Diff for: spring-javaformat-maven/spring-javaformat-maven-plugin/src/test/java/io/spring/format/maven/VerifyApply.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2021 the original author or authors.
+ * Copyright 2017-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,10 +17,11 @@
 package io.spring.javaformat.formatter;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.ArrayList;
-import java.util.Collection;
+import java.util.List;
 
 import io.spring.javaformat.config.JavaBaseline;
 import io.spring.javaformat.config.JavaFormatConfig;
@@ -47,7 +48,7 @@ protected final String read(File file) throws Exception {
 	}
 
 	protected static Item[] items(String expectedOverride) {
-		Collection<Item> items = new ArrayList<>();
+		List<Item> items = new ArrayList<>();
 		File sourceDir = new File("src/test/resources/source");
 		File expectedDir = new File("src/test/resources/expected");
 		File configDir = new File("src/test/resources/config");
@@ -59,12 +60,52 @@ protected static Item[] items(String expectedOverride) {
 			}
 			File config = new File(configDir, source.getName());
 			for (JavaBaseline javaBaseline : JavaBaseline.values()) {
-				items.add(new Item(javaBaseline, source, expected, config));
+				addItem(items, javaBaseline, source, expected, config);
 			}
 		}
 		return items.toArray(new Item[0]);
 	}
 
+	private static void addItem(List<Item> items, JavaBaseline javaBaseline, File source, File expected, File config) {
+		if (source.getName().contains("lineendings")) {
+			items.add(new Item(javaBaseline, copy(source, LineEnding.CR), copy(expected, LineEnding.CR), config));
+			items.add(new Item(javaBaseline, copy(source, LineEnding.LF), copy(expected, LineEnding.LF), config));
+			items.add(new Item(javaBaseline, copy(source, LineEnding.CRLF), copy(expected, LineEnding.CRLF), config));
+		}
+		else {
+			items.add(new Item(javaBaseline, source, expected, config));
+		}
+	}
+
+	private static File copy(File file, LineEnding lineEnding) {
+		try {
+			String[] name = file.getName().split("\\.");
+			File result = File.createTempFile(name[0] + "_" + lineEnding + "_", "." + name[1]);
+			String content = Files.readString(file.toPath());
+			content = content.replace("\r\n", "\n").replace('\r', '\n').replace("\n", lineEnding.ending());
+			Files.writeString(result.toPath(), content);
+			return result;
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException(ex);
+		}
+	}
+
+	enum LineEnding {
+
+		CR("\r"), LF("\n"), CRLF("\r\n");
+
+		private final String ending;
+
+		LineEnding(String ending) {
+			this.ending = ending;
+		}
+
+		String ending() {
+			return this.ending;
+		}
+	};
+
 	static class Item {
 
 		private final JavaBaseline javaBaseline;

Diff for: spring-javaformat/spring-javaformat-formatter-tests/src/test/java/io/spring/javaformat/formatter/AbstractFormatterTests.java

@@ -3,7 +3,6 @@ package correct;
 public class CorrectLf {
 
 	public static void main(String[] args) throws Exception {
-		// FIXME
 	}
 
 }

Diff for: spring-javaformat/spring-javaformat-formatter-tests/src/test/resources/.gitattributes

@@ -0,0 +1,7 @@
+package correct;
+
+public class CorrectLf {
+
+	public static void main(String[] args) throws Exception { }
+
+}

Diff for: spring-javaformat/spring-javaformat-formatter-tests/src/test/resources/expected/correct-cr.txt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2021 the original author or authors.
+ * Copyright 2017-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,8 +17,6 @@
 package io.spring.javaformat.formatter;
 
 import java.util.Map;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.text.edits.TextEdit;
@@ -58,11 +56,6 @@ public class Formatter {
 	 */
 	private static final int DEFAULT_INDENTATION_LEVEL = 0;
 
-	/**
-	 * Pattern that matches all line separators into named-capturing group "sep".
-	 */
-	private static final Pattern LINE_SEPARATOR_PATTERN = Pattern.compile("(?<sep>(\r\n|\r|\n))");
-
 	/**
 	 * The default line separator.
 	 */
@@ -130,9 +123,7 @@ public TextEdit format(String source, int offset, int length, String lineSeparat
 
 	public TextEdit format(int kind, String source, int offset, int length, int indentationLevel,
 			String lineSeparator) {
-		if (lineSeparator == null) {
-			lineSeparator = detectLineSeparator(source);
-		}
+		lineSeparator = (lineSeparator != null) ? lineSeparator : detectLineSeparator(source);
 		return this.delegate.format(kind, source, offset, length, indentationLevel, lineSeparator);
 	}
 
@@ -158,9 +149,7 @@ public TextEdit format(String source, IRegion[] regions, String lineSeparator) {
 	}
 
 	public TextEdit format(int kind, String source, IRegion[] regions, int indentationLevel, String lineSeparator) {
-		if (lineSeparator == null) {
-			lineSeparator = detectLineSeparator(source);
-		}
+		lineSeparator = (lineSeparator != null) ? lineSeparator : detectLineSeparator(source);
 		return this.delegate.format(kind, source, regions, indentationLevel, lineSeparator);
 	}
 
@@ -173,16 +162,17 @@ public void setOptions(Map<String, String> options) {
 	}
 
 	private String detectLineSeparator(String contents) {
-		Matcher matcher = LINE_SEPARATOR_PATTERN.matcher(contents);
-		if (!matcher.find()) {
-			return DEFAULT_LINE_SEPARATOR;
-		}
-		String firstMatch = matcher.group("sep");
-		while (matcher.find()) {
-			if (!matcher.group("sep").equals(firstMatch)) {
-				return DEFAULT_LINE_SEPARATOR;
+		int length = contents.length();
+		for (int i = 0; i < length; i++) {
+			char ch = contents.charAt(i);
+			boolean isLastChar = (i + 1) == length;
+			if (ch == '\r') {
+				return (isLastChar || contents.charAt(i + 1) != '\n') ? "\r" : "\r\n";
+			}
+			if (ch == '\n') {
+				return "\n";
 			}
 		}
-		return firstMatch;
+		return null;
 	}
 }