Bug 565844 - [14] Compiler rejects code with conditional expression in aI20200806-1800

switch expression's case

Change-Id: I4807e10b62a516606f85adb0346f141fead11062
Signed-off-by: Jay Arthanareeswaran <jarthana@in.ibm.com>

2 files changed, 114 insertions, 2 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
index 6bfeff329d..064afe61b8 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
@@ -5435,4 +5435,105 @@ public class SwitchExpressionsYieldTest extends AbstractRegressionTest {
 			},
 			"1");
 	}
+	public void testBug565844_1() {
+		runConformTest(
+				new String[] {
+					"X.java",
+					"public class X {\n"+
+					"    public final static int j = 5;\n" +
+					"    public static void main(String argv[]) {\n" +
+					"    	boolean b = \n" +
+					"    			switch (j) {\n" +
+					"    				case j != 1 ? 2 : 3 ->  true;\n" +
+					"    				default -> false;\n" +
+					"    			}; \n" +
+					"    	System.out.println(b);\n" +
+					"    }\n"+
+					"}"
+				},
+				"false");
+	}
+	public void testBug565844_2() {
+		runConformTest(
+				new String[] {
+					"X.java",
+					"public class X {\n"+
+					"    public final static int j = 2;\n" +
+					"    public static void main(String argv[]) {\n" +
+					"    	boolean b = \n" +
+					"    			switch (j) {\n" +
+					"    				case j != 1 ? 2 : (j == 2 ? 4 : 5) ->  true;\n" +
+					"    				default -> false;\n" +
+					"    			}; \n" +
+					"    	System.out.println(b);\n" +
+					"    }\n"+
+					"}"
+				},
+				"true");
+	}
+	public void testBug565844_3() {
+		runConformTest(
+				new String[] {
+					"X.java",
+					"public class X {\n"+
+					"    public final static int j = 5;\n" +
+					"    public static void main(String argv[]) {\n" +
+					"    	boolean b = \n" +
+					"    			switch (j) {\n" +
+					"    				case j != 1 ? 2 : 3 ->  {\n" +
+					"    						yield true;\n" +
+					"    					}\n" +
+					"    				default -> { yield false;}\n" +
+					"    			}; \n" +
+					"    	System.out.println(b);\n" +
+					"    }\n"+
+					"}"
+				},
+				"false");
+	}
+	public void testBug565844_4() {
+		runConformTest(
+				new String[] {
+					"X.java",
+					"public class X {\n"+
+					"    public final static int j = 5;\n" +
+					"    public static void main(String argv[]) {\n" +
+					"    	boolean b = \n" +
+					"    			switch (j) {\n" +
+					"    				case j != 1 ? 2 : 3 :  {\n" +
+					"    						yield true;\n" +
+					"    					}\n" +
+					"    				default : { yield false;}\n" +
+					"    			}; \n" +
+					"    	System.out.println(b);\n" +
+					"    }\n"+
+					"}"
+				},
+				"false");
+	}
+	public void testBug565844_5() {
+		runNegativeTest(
+				new String[] {
+					"X.java",
+					"public class X {\n"+
+					"    public static int j = 5;\n" +
+					"    public static void main(String argv[]) {\n" +
+					"    	boolean b = \n" +
+					"    			switch (j) {\n" +
+					"    				case j != 1 ? 2 : 3 ->  {\n" +
+					"    						yield true;\n" +
+					"    					}\n" +
+					"    				default -> { yield false;}\n" +
+					"    			}; \n" +
+					"    	System.out.println(b);\n" +
+					"    }\n"+
+					"}"
+				},
+				"----------\n" +
+				"1. ERROR in X.java (at line 6)\n" +
+				"	case j != 1 ? 2 : 3 ->  {\n" +
+				"	     ^^^^^^^^^^^^^^\n" +
+				"case expressions must be constant expressions\n" +
+				"----------\n");
+	}
 }
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/parser/Scanner.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/parser/Scanner.java
index 27abd0b8a5..020babfd86 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/parser/Scanner.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/parser/Scanner.java
@@ -111,6 +111,7 @@ public class Scanner implements TerminalTokens {
 
 	public boolean fakeInModule = false;
 	boolean inCase = false;
+	boolean inCondition = false;
 	/* package */ int yieldColons = -1;
 	boolean breakPreviewAllowed = false;
 	/**
@@ -1433,9 +1434,19 @@ private void updateCase(int token) {
 	if (token == TokenNamecase) {
 		this.inCase = true;
 		this.breakPreviewAllowed = true;
+	} else if (this.inCase) {
+		// This is for cases like this: case j != 1 ? 2 : (j == 2 ? 4 : 5) ->  true;
+		// Turn off the inCase until we are past the ':' that belongs to the ConditionalExpression
+		if (token == TokenNameQUESTION) {
+			this.inCondition = true;
+		} else if (this.inCondition) {
+			if (token == TokenNameCOLON) {
+				this.inCondition = false;
+			}
+		} else if (token == TokenNameCOLON || token == TokenNameARROW) {
+			this.inCase = false;
+		}
 	}
-	if (token == TokenNameCOLON || token == TokenNameARROW)
-		this.inCase = false;
 }
 public int getNextToken() throws InvalidInputException {