[23] exhaustiveness signalling difference between javac and ecj

+ clarify that flagDuplicateDefault() flags only conditionally, renamed to checkDuplicateDefault() - inside this method clarify that only one error is reported per loc. + remove all conflict reporting from CaseStatement.resolveCasePattern - will be done within SwitchStatement.resolve() anyway + remove IProblem.DuplicateTotalPattern and related code - all errors reported here coincided with a dominance error + adjust tests: no longer expect secondary errors fixes eclipse-jdt#2915
stephan-herrmann · Sep 7, 2024 · f508a96 · f508a96
1 parent 5892326
commit f508a96
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diff --git a/org.eclipse.jdt.core.compiler.batch/.settings/.api_filters b/org.eclipse.jdt.core.compiler.batch/.settings/.api_filters
@@ -23,6 +23,12 @@
                 <message_argument value="DisallowedStatementInPrologue"/>
             </message_arguments>
         </filter>
+        <filter comment="this preview constant (marked @noreference) is unnecesary" id="405864542">
+            <message_arguments>
+                <message_argument value="org.eclipse.jdt.core.compiler.IProblem"/>
+                <message_argument value="DuplicateTotalPattern"/>
+            </message_arguments>
+        </filter>
         <filter comment="renamed constant for JEP 482" id="405864542">
             <message_arguments>
                 <message_argument value="org.eclipse.jdt.core.compiler.IProblem"/>

diff --git a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/core/compiler/IProblem.java b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/core/compiler/IProblem.java
@@ -2537,9 +2537,6 @@ public interface IProblem {
 	/** @since 3.28
 	 * @noreference preview feature error */
 	int EnhancedSwitchMissingDefault = PreviewRelated + 1908;
-	/** @since 3.28
-	 * @noreference preview feature error */
-	int DuplicateTotalPattern = PreviewRelated + 1909;
 
 	 /** @since 3.34
 	 * @noreference preview feature error */

diff --git a/...ipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CaseStatement.java b/...ipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CaseStatement.java
@@ -179,7 +179,7 @@ public ResolvedCase[] resolveCase(BlockScope scope, TypeBinding switchExpression
 	this.swich = switchStatement;
 	scope.enclosingCase = this; // record entering in a switch case block
 	if (this.constantExpressions == Expression.NO_EXPRESSIONS) {
-		flagDuplicateDefault(scope, switchStatement, this);
+		checkDuplicateDefault(scope, switchStatement, this);
 		return ResolvedCase.UnresolvedCase;
 	}
 
@@ -192,7 +192,7 @@ public ResolvedCase[] resolveCase(BlockScope scope, TypeBinding switchExpression
 	for (Expression e : this.constantExpressions) {
 		count++;
 		if (e instanceof FakeDefaultLiteral) {
-			 flagDuplicateDefault(scope, switchStatement, this.constantExpressions.length > 1 ? e : this);
+			 checkDuplicateDefault(scope, switchStatement, this.constantExpressions.length > 1 ? e : this);
 			 if (count != 2 || nullCaseCount < 1) {
 				 scope.problemReporter().patternSwitchCaseDefaultOnlyAsSecond(e);
 			 }
@@ -267,16 +267,20 @@ public ResolvedCase[] resolveCase(BlockScope scope, TypeBinding switchExpression
 	return hasResolveErrors ? ResolvedCase.UnresolvedCase : cases.toArray(new ResolvedCase[cases.size()]);
 }
 
-private void flagDuplicateDefault(BlockScope scope, SwitchStatement switchStatement, ASTNode node) {
-	// remember the default case into the associated switch statement
-	if (switchStatement.defaultCase != null)
+/**
+ * Precondition: this is a default case.
+ * Check if (a) another default or (b) a total type pattern has been recorded already
+ */
+private void checkDuplicateDefault(BlockScope scope, SwitchStatement switchStatement, ASTNode node) {
+	if (switchStatement.defaultCase != null) {
 		scope.problemReporter().duplicateDefaultCase(node);
+	} else if ((switchStatement.switchBits & SwitchStatement.TotalPattern) != 0) {
+		scope.problemReporter().illegalTotalPatternWithDefault(this);
+	}
 
+	// remember the default case into the associated switch statement
 	// on error the last default will be the selected one ...
 	switchStatement.defaultCase = this;
-	if ((switchStatement.switchBits & SwitchStatement.TotalPattern) != 0) {
-		scope.problemReporter().illegalTotalPatternWithDefault(this);
-	}
 }
 
 @Override
@@ -394,17 +398,10 @@ private Constant resolveCasePattern(BlockScope scope, TypeBinding caseType, Type
 			}
 		}
 		if (e.coversType(expressionType, scope)) {
-			if ((switchStatement.switchBits & SwitchStatement.TotalPattern) != 0) {
-				scope.problemReporter().duplicateTotalPattern(e);
-				return IntConstant.fromValue(-1);
-			}
 			switchStatement.switchBits |= SwitchStatement.Exhaustive;
-			if (e.isUnconditional(expressionType, scope)) {
-				switchStatement.switchBits |= SwitchStatement.TotalPattern;
-				if (switchStatement.defaultCase != null && !(e instanceof RecordPattern))
-					scope.problemReporter().illegalTotalPatternWithDefault(this);
-			}
 			e.isTotalTypeNode = true;
+			if (e.isUnconditional(expressionType, scope)) // unguarded is implied from 'coversType()' above
+				switchStatement.switchBits |= SwitchStatement.TotalPattern;
 			if (switchStatement.nullCase == null)
 				constant = IntConstant.fromValue(-1);
 		}

diff --git a/...se.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java b/...se.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java
@@ -1192,8 +1192,7 @@ public void resolve(BlockScope upperScope) {
 					ResolvedCase[] constantsList;
 					final Statement statement = this.statements[i];
 					if (statement instanceof CaseStatement caseStmt) {
-						caseNullDefaultFound = caseNullDefaultFound ? caseNullDefaultFound
-								: isCaseStmtNullDefault(caseStmt);
+						caseNullDefaultFound |= isCaseStmtNullDefault(caseStmt);
 						defaultFound |= caseStmt.constantExpressions == Expression.NO_EXPRESSIONS;
 						constantsList = caseStmt.resolveCase(this.scope, expressionType, this);
 						patternVariables = statement.bindingsWhenTrue();

diff --git a/...dt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/problem/ProblemReporter.java b/...dt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/problem/ProblemReporter.java
@@ -12597,14 +12597,6 @@ public void enhancedSwitchMissingDefaultCase(ASTNode element) {
 			element.sourceStart,
 			element.sourceEnd);
 }
-public void duplicateTotalPattern(ASTNode element) {
-	this.handle(
-			IProblem.DuplicateTotalPattern,
-			NoArgument,
-			NoArgument,
-			element.sourceStart,
-			element.sourceEnd);
-}
 public void unexpectedTypeinSwitchPattern(TypeBinding type, ASTNode element) {
 	this.handle(
 			IProblem.UnexpectedTypeinSwitchPattern,

diff --git a/...jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/problem/messages.properties b/...jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/problem/messages.properties
@@ -1156,7 +1156,7 @@
 1906 = This case label is dominated by one of the preceding case labels
 1907 = Switch case cannot have both unconditional pattern and default label
 1908 = An enhanced switch statement should be exhaustive; a default label expected
-1909 = The switch statement cannot have more than one unconditional pattern
+# 1909 removed
 1910 = Unnecessary 'null' pattern, the switch selector expression cannot be null
 1911 = Unexpected type {0}, expected class or array type
 1920 = A null case label has to be either the only expression in a case label or the first expression followed only by a default

diff --git a/....compiler/src/org/eclipse/jdt/core/tests/compiler/regression/CompilerInvocationTests.java b/....compiler/src/org/eclipse/jdt/core/tests/compiler/regression/CompilerInvocationTests.java
@@ -1340,7 +1340,6 @@ class ProblemAttributes {
 	    expectedProblemAttributes.put("PatternDominated", new ProblemAttributes(true));
 	    expectedProblemAttributes.put("IllegalTotalPatternWithDefault", new ProblemAttributes(true));
 	    expectedProblemAttributes.put("EnhancedSwitchMissingDefault", new ProblemAttributes(true));
-	    expectedProblemAttributes.put("DuplicateTotalPattern", new ProblemAttributes(true));
 	    expectedProblemAttributes.put("UnexpectedTypeinSwitchPattern", new ProblemAttributes(true));
 	    expectedProblemAttributes.put("UnexpectedTypeinRecordPattern", new ProblemAttributes(true));
 	    expectedProblemAttributes.put("RecordPatternMismatch", new ProblemAttributes(true));
@@ -2474,7 +2473,6 @@ class ProblemAttributes {
 	    expectedProblemAttributes.put("PatternDominated", SKIP);
 	    expectedProblemAttributes.put("IllegalTotalPatternWithDefault", SKIP);
 	    expectedProblemAttributes.put("EnhancedSwitchMissingDefault", SKIP);
-	    expectedProblemAttributes.put("DuplicateTotalPattern", SKIP);
 	    expectedProblemAttributes.put("UnexpectedTypeinSwitchPattern", SKIP);
 	    expectedProblemAttributes.put("UnexpectedTypeinRecordPattern", SKIP);
 	    expectedProblemAttributes.put("RecordPatternMismatch", SKIP);

diff --git a/...ompiler/src/org/eclipse/jdt/core/tests/compiler/regression/PrimitiveInPatternsTestSH.java b/...ompiler/src/org/eclipse/jdt/core/tests/compiler/regression/PrimitiveInPatternsTestSH.java
@@ -2221,6 +2221,7 @@ public static void main(String... args) {
 	}
 
 	public void testCoversTypePlusDefault() {
+		// case int i "covers" type Integer but is not unconditional
 		runConformTest(new String[] {
 				"X.java",
 				"""
@@ -2241,6 +2242,72 @@ public static void main(String argv[]) {
 				},
 				"true");
 	}
+
+	public void testUnconditionPlusDefault() {
+		// case int i "covers" type int and is unconditional
+		// various combinations of dominance with/without default
+		runNegativeTest(new String[] {
+				"X.java",
+				"""
+				public class X  {
+					int foo1(int myInt) {
+						return switch (myInt) {
+							case int i  -> i;
+							default -> 0; // conflict with preceding total pattern (unguarded and unconditional)
+						};
+					}
+					int foo2(int myInt) {
+						return switch (myInt) { // swapped order of cases
+							default -> 0;
+							case int i  -> i; // conflict with preceding default
+						};
+					}
+					int foo3(int myInt) {
+						return switch (myInt) {
+							default -> 0;
+							case int i  -> i; // conflict with preceding default
+							case short s -> s; // additionally dominated by int i
+						};
+					}
+					int foo4(int myInt) {
+						return switch (myInt) {
+							case int i  -> i;
+							case short s -> s; // dominated by int i
+						};
+					}
+				}
+				"""
+				},
+				"""
+				----------
+				1. ERROR in X.java (at line 5)
+					default -> 0; // conflict with preceding total pattern (unguarded and unconditional)
+					^^^^^^^
+				Switch case cannot have both unconditional pattern and default label
+				----------
+				2. ERROR in X.java (at line 11)
+					case int i  -> i; // conflict with preceding default
+					     ^^^^^
+				This case label is dominated by one of the preceding case labels
+				----------
+				3. ERROR in X.java (at line 17)
+					case int i  -> i; // conflict with preceding default
+					     ^^^^^
+				This case label is dominated by one of the preceding case labels
+				----------
+				4. ERROR in X.java (at line 18)
+					case short s -> s; // additionally dominated by int i
+					     ^^^^^^^
+				This case label is dominated by one of the preceding case labels
+				----------
+				5. ERROR in X.java (at line 24)
+					case short s -> s; // dominated by int i
+					     ^^^^^^^
+				This case label is dominated by one of the preceding case labels
+				----------
+				""");
+	}
+
 	// test from spec
 	public void _testSpec001() {
 		runConformTest(new String[] {

diff --git a/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/RecordPatternTest.java b/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/RecordPatternTest.java
@@ -367,12 +367,6 @@ public void test009() {
 				"	case Rectangle(ColoredPoint(Point(int x, int y), Color c),\n" +
 				"				ColoredPoint(Point(int x1, int y1), Color c1)) -> {\n" +
 				"	     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" +
-				"The switch statement cannot have more than one unconditional pattern\n" +
-				"----------\n" +
-				"2. ERROR in X.java (at line 7)\n" +
-				"	case Rectangle(ColoredPoint(Point(int x, int y), Color c),\n" +
-				"				ColoredPoint(Point(int x1, int y1), Color c1)) -> {\n" +
-				"	     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" +
 				"This case label is dominated by one of the preceding case labels\n" +
 				"----------\n");
 	}

diff --git a/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java b/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java
@@ -2876,11 +2876,6 @@ public void testBug575048_01() {
 			"----------\n" +
 			"1. ERROR in X.java (at line 5)\n" +
 			"	case Integer i1 -> 0;\n" +
-			"	^^^^^^^^^^^^^^^\n" +
-			"Switch case cannot have both unconditional pattern and default label\n" +
-			"----------\n" +
-			"2. ERROR in X.java (at line 5)\n" +
-			"	case Integer i1 -> 0;\n" +
 			"	     ^^^^^^^^^^\n" +
 			"This case label is dominated by one of the preceding case labels\n" +
 			"----------\n");
@@ -3539,11 +3534,6 @@ public void testBug575047_06() {
 				"1. ERROR in X.java (at line 6)\n" +
 				"	case String s -> -1;\n" +
 				"	     ^^^^^^^^\n" +
-				"The switch statement cannot have more than one unconditional pattern\n" +
-				"----------\n" +
-				"2. ERROR in X.java (at line 6)\n" +
-				"	case String s -> -1;\n" +
-				"	     ^^^^^^^^\n" +
 				"This case label is dominated by one of the preceding case labels\n" +
 				"----------\n");
 	}
@@ -5751,11 +5741,6 @@ public void testIssue742_1() {
 				"1. ERROR in X.java (at line 7)\n" +
 				"	case Integer i ->                     // Error - dominated case label\n" +
 				"	     ^^^^^^^^^\n" +
-				"The switch statement cannot have more than one unconditional pattern\n" +
-				"----------\n" +
-				"2. ERROR in X.java (at line 7)\n" +
-				"	case Integer i ->                     // Error - dominated case label\n" +
-				"	     ^^^^^^^^^\n" +
 				"This case label is dominated by one of the preceding case labels\n" +
 				"----------\n");
 	}
@@ -5779,11 +5764,6 @@ public void testIssue742_2() {
 				"1. ERROR in X.java (at line 7)\n" +
 				"	case Integer i when true ->                     // Error - dominated case label\n" +
 				"	     ^^^^^^^^^\n" +
-				"The switch statement cannot have more than one unconditional pattern\n" +
-				"----------\n" +
-				"2. ERROR in X.java (at line 7)\n" +
-				"	case Integer i when true ->                     // Error - dominated case label\n" +
-				"	     ^^^^^^^^^\n" +
 				"This case label is dominated by one of the preceding case labels\n" +
 				"----------\n");
 	}