KT-3341 Prohibit val/var keywords for catch parameters

#KT-3341

compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/Errors.java

@@ -475,6 +475,7 @@ public interface Errors {
 
     DiagnosticFactory1<PsiElement, JetKeywordToken> VAL_OR_VAR_ON_LOOP_PARAMETER = DiagnosticFactory1.create(ERROR);
     DiagnosticFactory1<PsiElement, JetKeywordToken> VAL_OR_VAR_ON_FUN_PARAMETER = DiagnosticFactory1.create(ERROR);
+    DiagnosticFactory1<PsiElement, JetKeywordToken> VAL_OR_VAR_ON_CATCH_PARAMETER = DiagnosticFactory1.create(ERROR);
 
     // Backing fields
 

compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/rendering/DefaultErrorMessages.java

@@ -181,6 +181,7 @@ public class DefaultErrorMessages {
 
         MAP.put(VAL_OR_VAR_ON_LOOP_PARAMETER, "''{0}'' on loop parameter is not allowed", TO_STRING);
         MAP.put(VAL_OR_VAR_ON_FUN_PARAMETER, "''{0}'' on function parameter is not allowed", TO_STRING);
+        MAP.put(VAL_OR_VAR_ON_CATCH_PARAMETER, "''{0}'' on catch parameter is not allowed", TO_STRING);
 
         MAP.put(INITIALIZATION_USING_BACKING_FIELD_CUSTOM_SETTER,
                 "This property has a custom setter, so initialization using backing field required", NAME);

compiler/frontend/src/org/jetbrains/jet/lang/resolve/DescriptorResolver.java

@@ -712,7 +712,7 @@ public class DescriptorResolver {
                 annotationResolver.getResolvedAnnotations(parameter.getModifierList(), trace),
                 JetPsiUtil.safeName(parameter.getName()),
                 type,
-                parameter.isMutable());
+                false);
         trace.record(BindingContext.VALUE_PARAMETER, parameter, variableDescriptor);
         return variableDescriptor;
     }

compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/ControlStructureTypingVisitor.java

@@ -432,6 +432,11 @@ public class ControlStructureTypingVisitor extends ExpressionTypingVisitor {
             JetParameter catchParameter = catchClause.getCatchParameter();
             JetExpression catchBody = catchClause.getCatchBody();
             if (catchParameter != null) {
+                ASTNode valOrVarNode = catchParameter.getValOrVarNode();
+                if (valOrVarNode != null) {
+                    context.trace.report(VAL_OR_VAR_ON_CATCH_PARAMETER.on(valOrVarNode.getPsi(), ((JetKeywordToken) valOrVarNode.getElementType())));
+                }
+
                 VariableDescriptor variableDescriptor = context.expressionTypingServices.getDescriptorResolver().resolveLocalVariableDescriptor(
                         context.scope.getContainingDeclaration(), context.scope, catchParameter, context.trace);
                 JetType throwableType = KotlinBuiltIns.getInstance().getThrowable().getDefaultType();

compiler/testData/diagnostics/tests/controlStructures/valVarCatchParameter.kt

@@ -0,0 +1,13 @@
+fun f() {
+    try {
+    } catch (<!VAL_OR_VAR_ON_CATCH_PARAMETER!>val<!> e: Exception) {
+    }
+
+    try {
+    } catch (<!VAL_OR_VAR_ON_CATCH_PARAMETER!>var<!> e: Exception) {
+    }
+
+    try {
+    } catch (e: Exception) {
+    }
+}

compiler/tests/org/jetbrains/jet/checkers/JetDiagnosticsTestGenerated.java

@@ -1045,6 +1045,11 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
                 doTest("compiler/testData/diagnostics/tests/controlStructures/tryReturnType.kt");
             }
             
+            @TestMetadata("valVarCatchParameter.kt")
+            public void testValVarCatchParameter() throws Exception {
+                doTest("compiler/testData/diagnostics/tests/controlStructures/valVarCatchParameter.kt");
+            }
+            
             @TestMetadata("valVarLoopParameter.kt")
             public void testValVarLoopParameter() throws Exception {
                 doTest("compiler/testData/diagnostics/tests/controlStructures/valVarLoopParameter.kt");