Use Collator when sorting Eclipse JDT members

CHANGES.md

@@ -13,6 +13,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ### Added
 - Add `javaparserVersion` option to the Cleanthat step, allowing callers to override the JavaParser version pulled in transitively by Cleanthat. ([#2903](https://github.com/diffplug/spotless/pull/2903))
 ### Changes
+- Use Eclipse JDT's collator-based comparison when sorting Java members to better match Eclipse save actions. ([#2920](https://github.com/diffplug/spotless/pull/2920))
 - Bump default `cleanthat` version `2.24` -> `2.25`. ([#2903](https://github.com/diffplug/spotless/pull/2903))
 - Bump default `eclipse-jdt` version from `4.35` to `4.39`. ([#2912](https://github.com/diffplug/spotless/pull/2912))
 

lib-extra/src/jdt/java/com/diffplug/spotless/extra/glue/jdt/DefaultJavaElementComparator.java

@@ -15,6 +15,7 @@
  */
 package com.diffplug.spotless.extra.glue.jdt;
 
+import java.text.Collator;
 import java.util.Comparator;
 import java.util.List;
 import java.util.StringTokenizer;
@@ -61,6 +62,7 @@ class DefaultJavaElementComparator implements Comparator<BodyDeclaration> {
 	private final int[] memberCategoryOffsets;
 	private final boolean sortByVisibility;
 	private final int[] visibilityOffsets;
+	private final Collator collator;
 
 	static DefaultJavaElementComparator of(
 			boolean doNotSortFields,
@@ -95,6 +97,7 @@ static DefaultJavaElementComparator of(
 		this.memberCategoryOffsets = memberCategoryOffsets;
 		this.sortByVisibility = sortByVisibility;
 		this.visibilityOffsets = visibilityOffsets;
+		this.collator = Collator.getInstance();
 	}
 
 	@SuppressFBWarnings(value = "SF_SWITCH_NO_DEFAULT", justification = "we only accept valid tokens in the order string, otherwise we fall back to default value")
@@ -271,7 +274,7 @@ public int compare(BodyDeclaration bodyDeclaration1, BodyDeclaration bodyDeclara
 			String name2 = method2.getName().getIdentifier();
 
 			// method declarations (constructors) are sorted by name
-			int cmp = name1.compareTo(name2);
+			int cmp = collator.compare(name1, name2);
 			if (cmp != 0) {
 				return cmp;
 			}
@@ -286,7 +289,7 @@ public int compare(BodyDeclaration bodyDeclaration1, BodyDeclaration bodyDeclara
 			for (int i = 0; i < len; i++) {
 				SingleVariableDeclaration param1 = parameters1.get(i);
 				SingleVariableDeclaration param2 = parameters2.get(i);
-				cmp = buildSignature(param1.getType()).compareTo(buildSignature(param2.getType()));
+				cmp = collator.compare(buildSignature(param1.getType()), buildSignature(param2.getType()));
 				if (cmp != 0) {
 					return cmp;
 				}
@@ -377,7 +380,7 @@ private int preserveRelativeOrder(BodyDeclaration bodyDeclaration1, BodyDeclarat
 	}
 
 	private int compareNames(BodyDeclaration bodyDeclaration1, BodyDeclaration bodyDeclaration2, String name1, String name2) {
-		int cmp = name1.compareTo(name2);
+		int cmp = collator.compare(name1, name2);
 		if (cmp != 0) {
 			return cmp;
 		}

lib-extra/src/test/java/com/diffplug/spotless/extra/java/EclipseJdtFormatterStepSpecialCaseTest.java

@@ -107,4 +107,12 @@ void sort_members_local_enabled_true() {
 		StepHarness.forStep(builder.build())
 				.testResource("java/eclipse/SortExample.localEnabledTrue.test", "java/eclipse/SortExample.localEnabledTrue.clean");
 	}
+
+	@Test
+	void sort_members_uses_collator() {
+		EclipseJdtFormatterStep.Builder builder = EclipseJdtFormatterStep.createBuilder(TestProvisioner.mavenCentral(), TestP2Provisioner.defaultProvisioner());
+		builder.sortMembersEnabled(true);
+		StepHarness.forStep(builder.build())
+				.testResource("java/eclipse/SortExample.collator.test", "java/eclipse/SortExample.collator.clean");
+	}
 }

plugin-gradle/CHANGES.md

@@ -9,6 +9,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ### Fixed
 - Fix `tableTestFormatter` editorconfig cache not honoring `.editorconfig` changes across Gradle daemon runs due to a shared static `EditorConfigProvider`. ([#2893](https://github.com/diffplug/spotless/pull/2893))
 ### Changes
+- Use Eclipse JDT's collator-based comparison when sorting Java members to better match Eclipse save actions. ([#2920](https://github.com/diffplug/spotless/pull/2920))
 - Bump default `cleanthat` version `2.24` -> `2.25`. ([#2903](https://github.com/diffplug/spotless/pull/2903))
 - Bump default `eclipse-jdt` version from `4.35` to `4.39`. ([#2912](https://github.com/diffplug/spotless/pull/2912))
 

plugin-maven/CHANGES.md

@@ -6,6 +6,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ### Added
 - Add `<javaparserVersion>` option to `<cleanthat>`, allowing users to override the JavaParser version pulled in transitively by Cleanthat. ([#2903](https://github.com/diffplug/spotless/pull/2903))
 ### Changes
+- Use Eclipse JDT's collator-based comparison when sorting Java members to better match Eclipse save actions. ([#2920](https://github.com/diffplug/spotless/pull/2920))
 - Bump default `cleanthat` version `2.24` -> `2.25`. ([#2903](https://github.com/diffplug/spotless/pull/2903))
 - Bump default `eclipse-jdt` version from `4.35` to `4.39`. ([#2912](https://github.com/diffplug/spotless/pull/2912))
 

testlib/src/main/resources/java/eclipse/SortExample.collator.clean

@@ -0,0 +1,15 @@
+package com.diffplug.spotless.extra.glue.jdt;
+
+public class SortExample {
+	private static void mab() {
+	}
+
+	private static void mAc() {
+	}
+
+	private static void mp(String a, String b, int a) {
+	}
+
+	private static void mp(String a, String b, String p) {
+	}
+}

testlib/src/main/resources/java/eclipse/SortExample.collator.test

@@ -0,0 +1,15 @@
+package com.diffplug.spotless.extra.glue.jdt;
+
+public class SortExample {
+	private static void mAc() {
+	}
+
+	private static void mab() {
+	}
+
+	private static void mp(String a, String b, String p) {
+	}
+
+	private static void mp(String a, String b, int a) {
+	}
+}