From f8e479a020ebe91bdc758975d1bafb9b3ea0ee06 Mon Sep 17 00:00:00 2001
From: "Anna.Kozlova" <anna.kozlova@jetbrains.com>
Date: Thu, 31 Mar 2016 18:39:49 +0200
Subject: [PATCH] redundant cast: don't mark casts inside array index access
 expressions acceptable (IDEA-153661)

---
 .../src/com/intellij/psi/util/RedundantCastUtil.java   | 10 ++++++----
 .../inspection/redundantCast/IDEADEV25675/expected.xml |  5 +++++
 .../inspection/redundantCast/IDEADEV25675/src/A.java   |  7 +++++++
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/java/java-psi-api/src/com/intellij/psi/util/RedundantCastUtil.java b/java/java-psi-api/src/com/intellij/psi/util/RedundantCastUtil.java
index d4829aa8b268..3cb4bf3e1e60 100644
--- a/java/java-psi-api/src/com/intellij/psi/util/RedundantCastUtil.java
+++ b/java/java-psi-api/src/com/intellij/psi/util/RedundantCastUtil.java
@@ -642,7 +642,7 @@ public class RedundantCastUtil {
         }
       }
 
-      if (arrayAccessAtTheLeftSideOfAssignment(parent)) {
+      if (arrayAccessAtTheLeftSideOfAssignment(parent, typeCast)) {
         if (TypeConversionUtil.isAssignable(opType, castTo, false) && opType.getArrayDimensions() == castTo.getArrayDimensions()) {
           addToResults(typeCast);
         }
@@ -715,11 +715,13 @@ public class RedundantCastUtil {
       return true;
     }
 
-    private static boolean arrayAccessAtTheLeftSideOfAssignment(PsiElement element) {
-      PsiAssignmentExpression assignment = PsiTreeUtil.getParentOfType(element, PsiAssignmentExpression.class, false, PsiMember.class);
+    private static boolean arrayAccessAtTheLeftSideOfAssignment(PsiElement parent, PsiElement element) {
+      PsiAssignmentExpression assignment = PsiTreeUtil.getParentOfType(parent, PsiAssignmentExpression.class, false, PsiMember.class);
       if (assignment == null) return false;
       PsiExpression lExpression = assignment.getLExpression();
-      return PsiTreeUtil.isAncestor(lExpression, element, false) && lExpression instanceof PsiArrayAccessExpression;
+      return lExpression instanceof PsiArrayAccessExpression &&
+             PsiTreeUtil.isAncestor(lExpression, parent, false) &&
+             !PsiTreeUtil.isAncestor(((PsiArrayAccessExpression)lExpression).getIndexExpression(), element, false);
     }
   }
 
diff --git a/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/expected.xml b/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/expected.xml
index c440a49c4378..5ee65171181a 100644
--- a/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/expected.xml
+++ b/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/expected.xml
@@ -5,5 +5,10 @@
     <line>3</line>
     <description>Casting 'array' to String[] is redundant</description>
   </problem>
+  <problem>
+    <file>A.java</file>
+    <line>20</line>
+    <description>Casting '1' to 'Integer' is redundant</description>
+  </problem>
 </problems>
 
diff --git a/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/src/A.java b/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/src/A.java
index 074a0415074b..3c86677c178b 100644
--- a/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/src/A.java
+++ b/java/java-tests/testData/inspection/redundantCast/IDEADEV25675/src/A.java
@@ -12,4 +12,11 @@ public class Test {
       t.obj = new Object[1];
       ((Object[])t.obj)[0] = val;
     }
+
+    public static void arrayDims() {
+        int[] ints = new int[] {};
+        Object foo = 1;
+        ints[(Integer)  foo] = 0;
+        ints[(Integer)  1] = 0;
+    }
 }
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