Bug 576778 - IllegalArgumentException when hovering over anonymous classI20211028-1800

Change-Id: If333cd875324431624452b00a73ba2f4374b9360
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/186739
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Kenneth Styrberg <kenneth@kean.nu>
Reviewed-by: Jay Arthanareeswaran <jarthana@in.ibm.com>

2 files changed, 30 insertions, 3 deletions

diff --git a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/TypeResolveTests.java b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/TypeResolveTests.java
index 12ca893e3f..d9d9e55fdf 100644
--- a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/TypeResolveTests.java
+++ b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/TypeResolveTests.java
@@ -17,8 +17,6 @@ import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
 
-import junit.framework.Test;
-
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.jdt.core.Flags;
@@ -46,6 +44,8 @@ import org.eclipse.jdt.internal.core.NameLookup;
 import org.eclipse.jdt.internal.core.NameLookup.Answer;
 import org.eclipse.jdt.internal.core.SourceType;
 
+import junit.framework.Test;
+
 @SuppressWarnings({"rawtypes", "unchecked"})
 public class TypeResolveTests extends ModifyingResourceTests {
 	ICompilationUnit cu;
@@ -1670,4 +1670,31 @@ public void testBug575503() throws Exception{
 		deleteProject("P");
 	}
 }
+// https://bugs.eclipse.org/bugs/show_bug.cgi?id=576778
+public void testBug576778() throws Exception {
+	try {
+		createJava11Project("P", new String[] {"src"});
+		String source =    "package p;\n\n"
+				+"public class X {\n"
+				+ "  public static void main(String[] args) {\n"
+				+ "   var runnable = new Runnable() {\n"
+				+ "     public void run() {}\n"
+				+ "   };\n"
+				+ "   runnable.run();\n"
+				+ "  }\n"
+				+ "}\n";
+		createFolder("/P/src/p");
+		createFile("/P/src/p/X.java", source);
+		waitForAutoBuild();
+		ICompilationUnit unit = getCompilationUnit("/P/src/p/X.java");
+		String select = "runnable";
+		IJavaElement[] elements = unit.codeSelect(source.indexOf(select), select.length());
+		assertEquals("should not be empty", 1, elements.length);
+		ILocalVariable variable = (ILocalVariable) elements[0];
+		String signature= variable.getTypeSignature();
+		assertEquals("incorrect type", "Qvar;", signature);
+	} finally {
+		deleteProject("P");
+	}
+}
 }
diff --git a/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/SelectionRequestor.java b/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/SelectionRequestor.java
index 51f82007f0..f26a403067 100644
--- a/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/SelectionRequestor.java
+++ b/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/SelectionRequestor.java
@@ -481,7 +481,7 @@ public void acceptLocalVariable(LocalVariableBinding binding, org.eclipse.jdt.in
 	LocalVariable localVar = null;
 	if(parent != null) {
 		String typeSig = null;
-		if (local.type == null || local.type.isTypeNameVar(binding.declaringScope)) {
+		if (local.type == null || (local.type.isTypeNameVar(binding.declaringScope) && !binding.type.isAnonymousType())) {
 			if (local.initialization instanceof CastExpression) {
 				typeSig = Util.typeSignature(((CastExpression) local.initialization).type);
 			} else {