IDEA-109376 Groovy: "Final variable access" inspection doesn't report assignments to final parameters

plugins/groovy/src/org/jetbrains/plugins/groovy/GroovyBundle.properties

@@ -361,6 +361,7 @@ cannot.find.operator.overload.method=Cannot resolve index access with arguments
 named.arguments.are.not.allowed.inside.index.operations=Named arguments are not allowed inside index operations
 expected.0.to.be.inline.constant=Expected ''{0}'' to be an inline constant
 cannot.assign.a.value.to.final.field.0=Cannot assign a value to final field ''{0}''
+cannot.assign.a.value.to.final.parameter.0=Cannot assign a value to final parameter ''{0}''
 variable.0.might.not.have.been.initialized=Variable ''{0}'' might not have been initialized
 unexpected.symbol=Unexpected symbol
 statement.expected=Statement expected

plugins/groovy/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java

@@ -284,6 +284,7 @@ public class GroovyAnnotator extends GroovyElementVisitor {
     checkStringNameIdentifier(referenceExpression);
     checkThisOrSuperReferenceExpression(referenceExpression, myHolder);
     checkFinalFieldAccess(referenceExpression);
+    checkFinalParameterAccess(referenceExpression);
     if (ResolveUtil.isKeyOfMap(referenceExpression)) {
       PsiElement nameElement = referenceExpression.getReferenceNameElement();
       LOG.assertTrue(nameElement != null);
@@ -296,6 +297,19 @@ public class GroovyAnnotator extends GroovyElementVisitor {
     }
   }
 
+  private void checkFinalParameterAccess(GrReferenceExpression ref) {
+    final PsiElement resolved = ref.resolve();
+
+    if (resolved instanceof GrParameter) {
+      final GrParameter parameter = (GrParameter)resolved;
+      if (parameter.isPhysical() && parameter.hasModifierProperty(FINAL) && PsiUtil.isLValue(ref)) {
+        if (parameter.getDeclarationScope() instanceof PsiMethod) {
+          myHolder.createErrorAnnotation(ref, GroovyBundle.message("cannot.assign.a.value.to.final.parameter.0", parameter.getName()));
+        }
+      }
+    }
+  }
+
   private void checkFinalFieldAccess(@NotNull GrReferenceExpression ref) {
     final PsiElement resolved = ref.resolve();
 

plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/GroovyHighlightingTest.groovy

@@ -1426,4 +1426,28 @@ A.foo = 3 //no error
 }
 ''')
   }
+
+  void testFinalParameter() {
+    testHighlighting('''\
+def foo0(final i) {
+  <error descr="Cannot assign a value to final parameter 'i'">i</error> = 5
+  print i
+}
+
+def foo1(i) {
+  i = 5
+  print i
+}
+
+def foo2(final i = 4) {
+  <error descr="Cannot assign a value to final parameter 'i'">i</error> = 5
+  print i
+}
+
+def foo3(final i) {
+  print i
+}
+''')
+  }
+
 }