Bug 547125 [12] NPE in

compiler.problem.ProblemReporter.duplicateCase(...) on reconcile

Change-Id: Ie97b4e108f4ce1c15376cba577d55e40d148663c
Signed-off-by: Jay Arthanareeswaran <jarthana@in.ibm.com>

2 files changed, 87 insertions, 19 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionTest.java
index 66d8d68d83..31eba3a614 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionTest.java
@@ -699,10 +699,10 @@ public class SwitchExpressionTest extends AbstractRegressionTest {
 		};
 
 		String expectedProblemLog =
-						"----------\n" + 
-						"1. ERROR in X.java (at line 7)\n" + 
-						"	case SUNDAY : System.out.println(Day.SUNDAY);\n" + 
-						"	^^^^^^^^^^^\n" + 
+				"----------\n" + 
+						"1. ERROR in X.java (at line 4)\n" + 
+						"	case SATURDAY, SUNDAY: \n" + 
+						"	^^^^^^^^^^^^^^^^^^^^^\n" + 
 						"Duplicate case\n" + 
 						"----------\n" + 
 						"2. ERROR in X.java (at line 7)\n" + 
@@ -748,9 +748,9 @@ public class SwitchExpressionTest extends AbstractRegressionTest {
 						"	        ^^^\n" + 
 						"The enum constant MONDAY needs a corresponding case label in this enum switch on Day\n" + 
 						"----------\n" + 
-						"2. ERROR in X.java (at line 7)\n" + 
-						"	case SUNDAY, SATURDAY : \n" + 
-						"	^^^^^^^^^^^^^^^^^^^^^\n" + 
+						"2. ERROR in X.java (at line 4)\n" + 
+						"	case SATURDAY, SUNDAY: \n" + 
+						"	^^^^^^^^^^^^^^^^^^^^^\n" +
 						"Duplicate case\n" + 
 						"----------\n" + 
 						"3. ERROR in X.java (at line 7)\n" + 
@@ -1154,8 +1154,8 @@ public class SwitchExpressionTest extends AbstractRegressionTest {
 		};
 		String expectedProblemLog =
 				"----------\n" + 
-				"1. ERROR in X.java (at line 8)\n" + 
-				"	case 3, 4: \n" + 
+				"1. ERROR in X.java (at line 6)\n" + 
+				"	case 1, 3: \n" + 
 				"	^^^^^^^^^\n" + 
 				"Duplicate case\n" + 
 				"----------\n" + 
@@ -1195,8 +1195,8 @@ public class SwitchExpressionTest extends AbstractRegressionTest {
 		};
 		String expectedProblemLog =
 				"----------\n" + 
-				"1. ERROR in X.java (at line 8)\n" + 
-				"	case \"b\", \"c\": \n" + 
+				"1. ERROR in X.java (at line 6)\n" + 
+				"	case \"a\", \"b\": \n" + 
 				"	^^^^^^^^^^^^^\n" + 
 				"Duplicate case\n" + 
 				"----------\n" + 
@@ -2472,4 +2472,68 @@ public class SwitchExpressionTest extends AbstractRegressionTest {
 			"Illegal last statement in Switch expression case body - continue, return not allowed\n" + 
 			"----------\n");
 	}
+	public void testBug547125_01() {
+		this.runNegativeTest(
+			new String[] {
+				"X.java",
+				"public class X {\n" + 
+				"	void foo(Day day) {\n" + 
+				"		switch (day) {\n" + 
+				"		case SATURDAY, SUNDAY, SUNDAY:\n" + 
+				"			System.out.println(\"Weekend\");\n" + 
+				"		case MONDAY:\n" + 
+				"			System.out.println(\"Weekday\");\n" +
+				"		default: \n" + 
+				"		}\n" + 
+				"	}\n" + 
+				"}\n" + 
+				"\n" + 
+				"enum Day {\n" + 
+				"	MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY;\n" + 
+				"}",
+			},
+			"----------\n" + 
+			"1. ERROR in X.java (at line 4)\n" + 
+			"	case SATURDAY, SUNDAY, SUNDAY:\n" + 
+			"	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" + 
+			"Duplicate case\n" + 
+			"----------\n");
+	}
+	public void testBug547125_02() {
+		this.runNegativeTest(
+			new String[] {
+				"X.java",
+				"public class X {\n" + 
+				"	void foo(Day day) {\n" + 
+				"		switch (day) {\n" + 
+				"		case SATURDAY, SUNDAY, MONDAY:\n" + 
+				"			System.out.println(\"Weekend\");\n" + 
+				"		case MONDAY, SUNDAY:\n" + 
+				"			System.out.println(\"Weekday\");\n" +
+				"		default: \n" + 
+				"		}\n" + 
+				"	}\n" + 
+				"}\n" + 
+				"\n" + 
+				"enum Day {\n" + 
+				"	MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY;\n" + 
+				"}",
+			},
+			"----------\n" + 
+			"1. ERROR in X.java (at line 4)\n" + 
+			"	case SATURDAY, SUNDAY, MONDAY:\n" + 
+			"	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" + 
+			"Duplicate case\n" + 
+			"----------\n" + 
+			"2. ERROR in X.java (at line 6)\n" + 
+			"	case MONDAY, SUNDAY:\n" + 
+			"	^^^^^^^^^^^^^^^^^^^\n" + 
+			"Duplicate case\n" + 
+			"----------\n" + 
+			"3. ERROR in X.java (at line 6)\n" + 
+			"	case MONDAY, SUNDAY:\n" + 
+			"	^^^^^^^^^^^^^^^^^^^\n" + 
+			"Duplicate case\n" + 
+			"----------\n");
+	}
 }
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java
index b3203a4767..f32a048ec9 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchStatement.java
@@ -691,8 +691,10 @@ public class SwitchStatement extends Expression {
 					this.constMapping = new int[this.nConstants];
 				}
 				int counter = 0;
+				int caseCounter = 0;
 				for (int i = 0; i < length; i++) {
 					Constant[] constantsList;
+					int[] caseIndex = new int[this.nConstants];
 					final Statement statement = this.statements[i];
 					if (!(statement instanceof CaseStatement))  {
 						statement.resolve(this.scope);
@@ -707,26 +709,26 @@ public class SwitchStatement extends Expression {
 								//----check for duplicate case statement------------
 								for (int j = 0; j < counter; j++) {
 									if (this.constants[j] == key) {
-										reportDuplicateCase((CaseStatement) statement, this.cases[j], length);
+										reportDuplicateCase((CaseStatement) statement, this.cases[caseIndex[j]], length);
 									}
 								}
 								this.constants[counter] = key;
-								this.constMapping[counter] = counter;
-								counter++;
 							} else {
 								String key = con.stringValue();
 								//----check for duplicate case statement------------
 								for (int j = 0; j < counter; j++) {
 									if (this.stringConstants[j].equals(key)) {
-										reportDuplicateCase((CaseStatement) statement, this.cases[j], length);
+										reportDuplicateCase((CaseStatement) statement, this.cases[caseIndex[j]], length);
 									}
 								}
 								this.stringConstants[counter] = key;
-								this.constMapping[counter] = counter;
-								counter++;
 							}
+							this.constMapping[counter] = counter;
+							caseIndex[counter] = caseCounter;
+							counter++;
 						}
 					}
+					caseCounter++;
 				}
 				if (length != counter) { // resize constants array
 					if (!isStringSwitch) {
@@ -810,10 +812,12 @@ public class SwitchStatement extends Expression {
 	private void reportDuplicateCase(final CaseStatement duplicate, final CaseStatement original, int length) {
 		if (this.duplicateCaseStatements == null) {
 			this.scope.problemReporter().duplicateCase(original);
-			this.scope.problemReporter().duplicateCase(duplicate);
+			if (duplicate != original) 
+				this.scope.problemReporter().duplicateCase(duplicate);
 			this.duplicateCaseStatements = new CaseStatement[length];
 			this.duplicateCaseStatements[this.duplicateCaseStatementsCounter++] = original;
-			this.duplicateCaseStatements[this.duplicateCaseStatementsCounter++] = duplicate;
+			if (duplicate != original) 
+				this.duplicateCaseStatements[this.duplicateCaseStatementsCounter++] = duplicate;
 		} else {
 			boolean found = false;
 			searchReportedDuplicate: for (int k = 2; k < this.duplicateCaseStatementsCounter; k++) {