From 79ac82614e6dc71d8a7fcf802eee07098026adb8 Mon Sep 17 00:00:00 2001
From: Markus Keller
Date: Tue, 21 Feb 2012 18:57:56 +0100
Subject: Bug 371078: [clean up] Regression: Remove unnecessary casts deletes
 code / causes compile errors

---
 .../eclipse/jdt/ui/tests/quickfix/CleanUpTest.java | 57 +++++++++++++++++++++-
 .../jdt/internal/corext/fix/UnusedCodeFix.java     | 52 +++++++++++++++-----
 2 files changed, 94 insertions(+), 15 deletions(-)

diff --git a/org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/quickfix/CleanUpTest.java b/org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/quickfix/CleanUpTest.java
index a465082b9e..d2b114a2da 100644
--- a/org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/quickfix/CleanUpTest.java
+++ b/org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/quickfix/CleanUpTest.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2011 IBM Corporation and others.
+ * Copyright (c) 2000, 2012 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -927,7 +927,7 @@ public class CleanUpTest extends CleanUpTestCase {
 		buf.append("\n");
 		buf.append("public class E1 {\n");
 		buf.append("    public void foo(Integer n) {\n");
-		buf.append("        int i = (n).intValue();\n");
+		buf.append("        int i = n.intValue();\n");
 		buf.append("    }\n");
 		buf.append("}\n");
 		String expected1= buf.toString();
@@ -962,6 +962,59 @@ public class CleanUpTest extends CleanUpTestCase {
 		assertRefactoringResultAsExpected(new ICompilationUnit[] { cu1 }, new String[] { expected1 });
 	}
 
+	public void testUnusedCodeBug371078_1() throws Exception {
+		IPackageFragment pack1= fSourceFolder.createPackageFragment("test1", false, null);
+		StringBuffer buf= new StringBuffer();
+
+		buf.append("package test1;\n");
+		buf.append("class E1 {\n");
+		buf.append("    public static Object create(final int a, final int b) {\n");
+		buf.append("        return (Double) ((double) (a * Math.pow(10, -b)));\n");
+		buf.append("    }\n");
+		buf.append("}\n");
+
+		ICompilationUnit cu1= pack1.createCompilationUnit("IntComp.java", buf.toString(), false, null);
+
+		enable(CleanUpConstants.REMOVE_UNNECESSARY_CASTS);
+
+		buf= new StringBuffer();
+		buf.append("package test1;\n");
+		buf.append("class E1 {\n");
+		buf.append("    public static Object create(final int a, final int b) {\n");
+		buf.append("        return (a * Math.pow(10, -b));\n");
+		buf.append("    }\n");
+		buf.append("}\n");
+		String expected1= buf.toString();
+
+		assertRefactoringResultAsExpected(new ICompilationUnit[] { cu1 }, new String[] { expected1 });
+	}
+
+	public void testUnusedCodeBug371078_2() throws Exception {
+		IPackageFragment pack1= fSourceFolder.createPackageFragment("test1", false, null);
+		StringBuffer buf= new StringBuffer();
+		
+		buf.append("package test1;\n");
+		buf.append("public class NestedCasts {\n");
+		buf.append("	void foo(Integer i) {\n");
+		buf.append("		Object o= ((((Number) (((Integer) i)))));\n");
+		buf.append("	}\n");
+		buf.append("}\n");
+		ICompilationUnit cu1= pack1.createCompilationUnit("NestedCasts.java", buf.toString(), false, null);
+		
+		enable(CleanUpConstants.REMOVE_UNNECESSARY_CASTS);
+		
+		buf= new StringBuffer();
+		buf.append("package test1;\n");
+		buf.append("public class NestedCasts {\n");
+		buf.append("	void foo(Integer i) {\n");
+		buf.append("		Object o= i;\n");
+		buf.append("	}\n");
+		buf.append("}\n");
+		String expected1= buf.toString();
+		
+		assertRefactoringResultAsExpected(new ICompilationUnit[] { cu1 }, new String[] { expected1 });
+	}
+	
 	public void testJava5001() throws Exception {
 		IPackageFragment pack1= fSourceFolder.createPackageFragment("test1", false, null);
 		StringBuffer buf= new StringBuffer();
diff --git a/org.eclipse.jdt.ui/core extension/org/eclipse/jdt/internal/corext/fix/UnusedCodeFix.java b/org.eclipse.jdt.ui/core extension/org/eclipse/jdt/internal/corext/fix/UnusedCodeFix.java
index b43d979b86..341d8baa6e 100644
--- a/org.eclipse.jdt.ui/core extension/org/eclipse/jdt/internal/corext/fix/UnusedCodeFix.java	
+++ b/org.eclipse.jdt.ui/core extension/org/eclipse/jdt/internal/corext/fix/UnusedCodeFix.java	
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2011 IBM Corporation and others.
+ * Copyright (c) 2000, 2012 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -474,26 +474,52 @@ public class UnusedCodeFix extends CompilationUnitRewriteOperationsFix {
 			while (fUnnecessaryCasts.size() > 0) {
 				CastExpression castExpression= fUnnecessaryCasts.iterator().next();
 				fUnnecessaryCasts.remove(castExpression);
+				
+				/*
+				 * ASTRewrite doesn't allow replacing (deleting) of moved nodes. To solve problems
+				 * with nested casts, we need to replace all casts at once.
+				 * 
+				 * The loops first proceed downwards to find the innermost expression that stays in the result
+				 * and then proceeds towards the top to find the outermost cast that needs to be replaced.
+				 * Both loops also skip unnecessary parenthesized nodes.
+				 */
 				CastExpression down= castExpression;
-				while (fUnnecessaryCasts.contains(down.getExpression())) {
-					down= (CastExpression)down.getExpression();
-					fUnnecessaryCasts.remove(down);
+				ASTNode downChild= down.getExpression();
+				while (true) {
+					if (fUnnecessaryCasts.contains(downChild)) {
+						down= (CastExpression) downChild;
+						fUnnecessaryCasts.remove(down);
+						downChild= down.getExpression();
+					} else if (downChild instanceof ParenthesizedExpression) {
+						if (!NecessaryParenthesesChecker.needsParentheses(castExpression, downChild.getParent(), downChild.getLocationInParent())) {
+							downChild= ((ParenthesizedExpression) downChild).getExpression();
+							if (downChild instanceof CastExpression)
+								down= (CastExpression) downChild;
+						} else {
+							break;
+						}
+					} else {
+						break;
+					}
 				}
 
 				Expression expression= down.getExpression();
 				ASTNode move= rewrite.createMoveTarget(expression);
 
-				CastExpression top= castExpression;
-				while (fUnnecessaryCasts.contains(top.getParent())) {
-					top= (CastExpression)top.getParent();
-					fUnnecessaryCasts.remove(top);
+				ASTNode top= castExpression;
+				while (true) {
+					ASTNode parent= top.getParent();
+					if (fUnnecessaryCasts.contains(parent)) {
+						top= parent;
+						fUnnecessaryCasts.remove(top);
+					} else if (parent instanceof ParenthesizedExpression && !NecessaryParenthesesChecker.needsParentheses(expression, parent, top.getLocationInParent())) {
+						top= parent;
+					} else {
+						break;
+					}
 				}
 
-				ASTNode toReplace= top;
-				if (top.getParent() instanceof ParenthesizedExpression && !NecessaryParenthesesChecker.needsParentheses(expression, top.getParent(), top.getLocationInParent())) {
-					toReplace= top.getParent();
-				}
-				rewrite.replace(toReplace, move, group);
+				rewrite.replace(top, move, group);
 			}
 		}
 	}
-- 
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