Attachment #190741 for bug #339250




/*******************************************************************************
 * Copyright (c) 2000, 2011 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

	if (this.resolvedType.id != T_JavaLangString) {
		this.lhs.checkNPE(currentScope, flowContext, flowInfo);
	}
	flowInfo = ((Reference) this.lhs).analyseAssignment(currentScope, flowContext, flowInfo, this, true).unconditionalInits();
	if (this.resolvedType.id == T_JavaLangString) {
		// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
		LocalVariableBinding local = this.lhs.localVariableBinding();
		if (local != null && this.resolvedType.id == T_JavaLangString) {
			// compound assignment results in a definitely non null value for String
			flowInfo.markAsDefinitelyNonNull(local);
			if (flowContext.initsOnFinally != null)
				flowContext.initsOnFinally.markAsDefinitelyNonNull(local);
		}
	}
	return flowInfo;
}

	public boolean checkCastCompatibility() {




// Only the highest compliance level is run; add the VM argument
// -Dcompliance=1.4 (for example) to lower it if needed
static {
//		TESTS_NAMES = new String[] { "testBug339250" };
//		TESTS_NUMBERS = new int[] { 561 };
//		TESTS_RANGE = new int[] { 1, 2049 };
}

		"    17  return\n";
	checkDisassembledClassFile(OUTPUT_DIR + File.separator + "X.class", "X", expectedOutput);
}
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
// Check code gen
public void testBug339250() throws Exception {
	Map options = getCompilerOptions();
	options.put(CompilerOptions.OPTION_ReportRedundantNullCheck, CompilerOptions.WARNING);
	this.runConformTest(
		new String[] {
			"X.java",
			"public class X {\n" + 
			"	public static void main(String[] args) {\n" + 
			"		String s = null;\n" +
			"		s += \"correctly\";\n" +
			"		if (s != null) {\n" + 	// s cannot be null
			"			System.out.println(\"It works \" + s);\n" + 
			"		}\n" +
			"	}\n" + 
			"}",
		},
		"It works nullcorrectly",
		null,
		true,
		null,
		options,
		null);
}
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
// Check that the redundant null check warning is correctly produced
public void testBug339250a() throws Exception {
	this.runNegativeTest(
		new String[] {
			"X.java",
			"public class X {\n" + 
			"	public static void main(String[] args) {\n" + 
			"		String s = null;\n" +
			"		s += \"correctly\";\n" +
			"		if (s != null) {\n" + 	// s cannot be null
			"			System.out.println(\"It works \" + s);\n" + 
			"		}\n" +
			"	}\n" + 
			"}",
		},
		"----------\n" + 
		"1. ERROR in X.java (at line 5)\n" + 
		"	if (s != null) {\n" + 
		"	    ^\n" + 
		"Redundant null check: The variable s cannot be null at this location\n" + 
		"----------\n");
}
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
// Check that the redundant null check warning is correctly produced
public void testBug339250b() throws Exception {
	this.runNegativeTest(
		new String[] {
			"X.java",
			"public class X {\n" + 
			"	public static void main(String[] args) {\n" + 
			"		String s = null;\n" +
			"		s += null;\n" +
			"		if (s != null) {\n" + 	// s is definitely not null
			"			System.out.println(\"It works \" + s);\n" + 
			"	    }\n" + 
			"		s = null;\n" +
			"		if (s != null) {\n" + 	// s is definitely null
			"			System.out.println(\"Fails \" + s);\n" + 
			"	    } else {\n" + 
			"			System.out.println(\"Works second time too \" + s);\n" +
			"       }\n" + 
			"	}\n" + 
			"}",
		},
		"----------\n" + 
		"1. ERROR in X.java (at line 5)\n" + 
		"	if (s != null) {\n" + 
		"	    ^\n" + 
		"Redundant null check: The variable s cannot be null at this location\n" + 
		"----------\n" + 
		"2. ERROR in X.java (at line 9)\n" + 
		"	if (s != null) {\n" + 
		"	    ^\n" + 
		"Null comparison always yields false: The variable s can only be null at this location\n" + 
		"----------\n" + 
		"3. WARNING in X.java (at line 9)\n" + 
		"	if (s != null) {\n" + 
		"			System.out.println(\"Fails \" + s);\n" + 
		"	    } else {\n" + 
		"	               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" + 
		"Dead code\n" + 
		"----------\n");
}
}

Return to bug 339250

Lines 44-50 Link Here

(-)src/org/eclipse/jdt/core/tests/compiler/regression/NullReferenceTest.java (-1 / +90 lines)
44	// Only the highest compliance level is run; add the VM argument	44	// Only the highest compliance level is run; add the VM argument
45	// -Dcompliance=1.4 (for example) to lower it if needed	45	// -Dcompliance=1.4 (for example) to lower it if needed
46	static {	46	static {
47	// TESTS_NAMES = new String[] { "testBug336428e" };	47	// TESTS_NAMES = new String[] { "testBug339250" };
48	// TESTS_NUMBERS = new int[] { 561 };	48	// TESTS_NUMBERS = new int[] { 561 };
49	// TESTS_RANGE = new int[] { 1, 2049 };	49	// TESTS_RANGE = new int[] { 1, 2049 };
50	}	50	}
Lines 14441-14444 Link Here
14441	" 17 return\n";	14441	" 17 return\n";
14442	checkDisassembledClassFile(OUTPUT_DIR + File.separator + "X.class", "X", expectedOutput);	14442	checkDisassembledClassFile(OUTPUT_DIR + File.separator + "X.class", "X", expectedOutput);
14443	}	14443	}
		14444	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
		14445	// Check code gen
		14446	public void testBug339250() throws Exception {
		14447	Map options = getCompilerOptions();
		14448	options.put(CompilerOptions.OPTION_ReportRedundantNullCheck, CompilerOptions.WARNING);
		14449	this.runConformTest(
		14450	new String[] {
		14451	"X.java",
		14452	"public class X {\n" +
		14453	" public static void main(String[] args) {\n" +
		14454	" String s = null;\n" +
		14455	" s += \"correctly\";\n" +
		14456	" if (s != null) {\n" + // s cannot be null
		14457	" System.out.println(\"It works \" + s);\n" +
		14458	" }\n" +
		14459	" }\n" +
		14460	"}",
		14461	},
		14462	"It works nullcorrectly",
		14463	null,
		14464	true,
		14465	null,
		14466	options,
		14467	null);
		14468	}
		14469	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
		14470	// Check that the redundant null check warning is correctly produced
		14471	public void testBug339250a() throws Exception {
		14472	this.runNegativeTest(
		14473	new String[] {
		14474	"X.java",
		14475	"public class X {\n" +
		14476	" public static void main(String[] args) {\n" +
		14477	" String s = null;\n" +
		14478	" s += \"correctly\";\n" +
		14479	" if (s != null) {\n" + // s cannot be null
		14480	" System.out.println(\"It works \" + s);\n" +
		14481	" }\n" +
		14482	" }\n" +
		14483	"}",
		14484	},
		14485	"----------\n" +
		14486	"1. ERROR in X.java (at line 5)\n" +
		14487	" if (s != null) {\n" +
		14488	" ^\n" +
		14489	"Redundant null check: The variable s cannot be null at this location\n" +
		14490	"----------\n");
		14491	}
		14492	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
		14493	// Check that the redundant null check warning is correctly produced
		14494	public void testBug339250b() throws Exception {
		14495	this.runNegativeTest(
		14496	new String[] {
		14497	"X.java",
		14498	"public class X {\n" +
		14499	" public static void main(String[] args) {\n" +
		14500	" String s = null;\n" +
		14501	" s += null;\n" +
		14502	" if (s != null) {\n" + // s is definitely not null
		14503	" System.out.println(\"It works \" + s);\n" +
		14504	" }\n" +
		14505	" s = null;\n" +
		14506	" if (s != null) {\n" + // s is definitely null
		14507	" System.out.println(\"Fails \" + s);\n" +
14508	" } else {\n" +
14509	" System.out.println(\"Works second time too \" + s);\n" +
14510	" }\n" +
14511	" }\n" +
14512	"}",
14513	},
14514	"----------\n" +
14515	"1. ERROR in X.java (at line 5)\n" +
14516	" if (s != null) {\n" +
14517	" ^\n" +
14518	"Redundant null check: The variable s cannot be null at this location\n" +
14519	"----------\n" +
14520	"2. ERROR in X.java (at line 9)\n" +
14521	" if (s != null) {\n" +
14522	" ^\n" +
14523	"Null comparison always yields false: The variable s can only be null at this location\n" +
14524	"----------\n" +
14525	"3. WARNING in X.java (at line 9)\n" +
14526	" if (s != null) {\n" +
14527	" System.out.println(\"Fails \" + s);\n" +
14528	" } else {\n" +
14529	" ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n" +
14530	"Dead code\n" +
14531	"----------\n");
14532	}
14444	}	14533	}

Lines 1-5 Link Here

(-)compiler/org/eclipse/jdt/internal/compiler/ast/CompoundAssignment.java (-2 / +13 lines)
1	/*******************************************************************************	1	/*******************************************************************************
2	* Copyright (c) 2000, 2009 IBM Corporation and others.	2	* Copyright (c) 2000, 2011 IBM Corporation and others.
3	* All rights reserved. This program and the accompanying materials	3	* All rights reserved. This program and the accompanying materials
4	* are made available under the terms of the Eclipse Public License v1.0	4	* are made available under the terms of the Eclipse Public License v1.0
5	* which accompanies this distribution, and is available at	5	* which accompanies this distribution, and is available at
Lines 42-48 Link Here
42	if (this.resolvedType.id != T_JavaLangString) {	42	if (this.resolvedType.id != T_JavaLangString) {
43	this.lhs.checkNPE(currentScope, flowContext, flowInfo);	43	this.lhs.checkNPE(currentScope, flowContext, flowInfo);
44	}	44	}
45	return ((Reference) this.lhs).analyseAssignment(currentScope, flowContext, flowInfo, this, true).unconditionalInits();	45	flowInfo = ((Reference) this.lhs).analyseAssignment(currentScope, flowContext, flowInfo, this, true).unconditionalInits();
		46	if (this.resolvedType.id == T_JavaLangString) {
		47	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=339250
		48	LocalVariableBinding local = this.lhs.localVariableBinding();
		49	if (local != null && this.resolvedType.id == T_JavaLangString) {
		50	// compound assignment results in a definitely non null value for String
		51	flowInfo.markAsDefinitelyNonNull(local);
		52	if (flowContext.initsOnFinally != null)
		53	flowContext.initsOnFinally.markAsDefinitelyNonNull(local);
		54	}
		55	}
		56	return flowInfo;
46	}	57	}
47		58
48	public boolean checkCastCompatibility() {	59	public boolean checkCastCompatibility() {