From 46d8a7daf17c6b37ddf977cbc6edf07588ceab2b Mon Sep 17 00:00:00 2001
From: Max Medvedev <maxim.medvedev@jetbrains.com>
Date: Mon, 1 Jul 2013 18:32:56 +0400
Subject: [PATCH] IDEA-109376 Groovy: "Final variable access" inspection
 doesn't report assignments to final parameters

---
 .../plugins/groovy/GroovyBundle.properties    |  1 +
 .../groovy/annotator/GroovyAnnotator.java     | 14 +++++++++++
 .../GroovyHighlightingTest.groovy             | 24 +++++++++++++++++++
 3 files changed, 39 insertions(+)

diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/GroovyBundle.properties b/plugins/groovy/src/org/jetbrains/plugins/groovy/GroovyBundle.properties
index 89801b5de43c..dc4af2ee9f40 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/GroovyBundle.properties
+++ b/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
diff --git a/plugins/groovy/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java b/plugins/groovy/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java
index c217be6ab35b..7a570e0a3c9f 100644
--- a/plugins/groovy/src/org/jetbrains/plugins/groovy/annotator/GroovyAnnotator.java
+++ b/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();
 
diff --git a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/GroovyHighlightingTest.groovy b/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/GroovyHighlightingTest.groovy
index 0331e2e4f6c9..7dc1e6fd9186 100644
--- a/plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/GroovyHighlightingTest.groovy
+++ b/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
+}
+''')
+  }
+
 }
\ No newline at end of file