Attachment #177976 for bug #133125




 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Stephen Herrmann <stephan@cs.tu-berlin.de> -  Contribution for bug 133125
 *******************************************************************************/
package org.eclipse.jdt.internal.compiler.ast;


	if (ifTrueNullStatus == ifFalseNullStatus) {
		return ifTrueNullStatus;
	}
	// is there a chance of null? -> potentially null
	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
	switch (ifTrueNullStatus) {
		case FlowInfo.NULL:
		case FlowInfo.POTENTIALLY_NULL:
			return FlowInfo.POTENTIALLY_NULL;
	}
	switch (ifFalseNullStatus) {
		case FlowInfo.NULL:
		case FlowInfo.POTENTIALLY_NULL:
			return FlowInfo.POTENTIALLY_NULL;
	}
	return FlowInfo.UNKNOWN;
	// cannot decide which branch to take, and they disagree
}




 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *     Stephan Herrmann <stephan@cs.tu-berlin.de> - Contribution for bugs 133125, 292478, 319201 and 320170
 *******************************************************************************/
package org.eclipse.jdt.core.tests.compiler.regression;


}

// null analysis -- conditional expression
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
public void test0034_conditional_expression() {
// the null status of an expression and the code analysis of the said expression; this
// case is simplistic: we need a value (here, potentially null), that is *not* carried
// by the current embodiment of the flow info; other cases are less trivial in which
// side effects on variables could introduce errors into after the facts evaluations;
// one possible trick would be to add a slot for this
// other path: use a tainted unknown expression status; does not seem to cope well
// with o = (o ==  null ? new Object() : o)
// TODO (maxime) https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
public void _test0034_conditional_expression() {
	this.runNegativeTest(
		new String[] {
			"X.java",

			"    o.toString();\n" +
			"  }\n" +
			"}\n"},
			"----------\n" +
			"1. ERROR in X.java (at line 5)\n" +
			"	o.toString();\n" +
			"	^\n" +
			"Potential null pointer access: The variable o may be null at this location\n" +
			"----------\n");
}

// null analysis -- conditional expression
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
// variant with constant condition
public void test0034_conditional_expression_2() {
	this.runConformTest(
		new String[] {
			"X.java",
			"public class X {\n" +
			"  boolean b;\n" +
			"  void foo() {\n" +
			"    Object o = false ? null : new Object();\n" +
			"    o.toString();\n" +
			"  }\n" +
			"}\n"},
			"");
}

// null analysis -- conditional expression
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
public void test0034_conditional_expression_3() {
	this.runNegativeTest(
		new String[] {
			"X.java",
			"public class X {\n" +
			"  boolean b;\n" +
			"  void foo(Object a) {\n" +
			" 	 if (a == null) {}\n" +
			"    Object o = b ? a : new Object();\n" +
			"    o.toString();\n" +
			"  }\n" +
			"}\n"},
			"----------\n" +
			"1. ERROR in X.java (at line 6)\n" +
			"	o.toString();\n" +
			"	^\n" +
			"Potential null pointer access: The variable o may be null at this location\n" +
			"----------\n");
}

// null analysis -- conditional expression
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
// variant with dependency between condition and expression - LocalDeclaration
// TODO(stephan) cannot analyse this flow dependency
public void _test0034_conditional_expression_4() {
	this.runConformTest(
		new String[] {
			"X.java",
			"public class X {\n" +
			"  boolean b;\n" +
			"  void foo(Object u) {\n" +
			"    if (u == null) {}\n" + //taint
			"    Object o = (u == null) ? new Object() : u;\n" +
			"    o.toString();\n" +
			"  }\n" +
			"}\n"},
			"");
}

// null analysis -- conditional expression
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
// variant with dependency between condition and expression - Assignment
// TODO(stephan) cannot analyse this flow dependency
public void _test0034_conditional_expression_5() {
	this.runConformTest(
		new String[] {
			"X.java",
			"public class X {\n" +
			"  boolean b;\n" +
			"  void foo(Object u) {\n" +
			"    if (u == null) {}\n" + //taint
			"    Object o;\n" +
			"    o = (u == null) ? new Object() : u;\n" +
			"    o.toString();\n" +
			"  }\n" +
			"}\n"},
			"");
}

// null analysis -- conditional expression

Return to bug 133125

Lines 7-13 Link Here

(-)src/org/eclipse/jdt/core/tests/compiler/regression/NullReferenceTest.java (-18 / +87 lines)
7	*	7	*
8	* Contributors:	8	* Contributors:
9	* IBM Corporation - initial API and implementation	9	* IBM Corporation - initial API and implementation
10	* Stephan Herrmann <stephan@cs.tu-berlin.de> - Contribution for bugs 292478, 319201 and 320170	10	* Stephan Herrmann <stephan@cs.tu-berlin.de> - Contribution for bugs 133125, 292478, 319201 and 320170
11	*******************************************************************************/	11	*******************************************************************************/
12	package org.eclipse.jdt.core.tests.compiler.regression;	12	package org.eclipse.jdt.core.tests.compiler.regression;
13		13
Lines 729-745 Link Here
729	}	729	}
730		730
731	// null analysis -- conditional expression	731	// null analysis -- conditional expression
732	// TODO (maxime) fix - may consider simultaneous computation of expression null status	732	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
733	// this case is one of those which raise the need for the simultaneous calculation of	733	public void test0034_conditional_expression() {
734	// the null status of an expression and the code analysis of the said expression; this
735	// case is simplistic: we need a value (here, potentially null), that is not carried
736	// by the current embodiment of the flow info; other cases are less trivial in which
737	// side effects on variables could introduce errors into after the facts evaluations;
738	// one possible trick would be to add a slot for this
739	// other path: use a tainted unknown expression status; does not seem to cope well
740	// with o = (o == null ? new Object() : o)
741	// TODO (maxime) https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
742	public void _test0034_conditional_expression() {
743	this.runNegativeTest(	734	this.runNegativeTest(
744	new String[] {	735	new String[] {
745	"X.java",	736	"X.java",
Lines 750-761 Link Here
750	" o.toString();\n" +	741	" o.toString();\n" +
751	" }\n" +	742	" }\n" +
752	"}\n"},	743	"}\n"},
753	"----------\n" +	744	"----------\n" +
754	"1. ERROR in X.java (at line 4)\n" +	745	"1. ERROR in X.java (at line 5)\n" +
755	" o.toString();\n" +	746	" o.toString();\n" +
756	" ^\n" +	747	" ^\n" +
757	"The variable o may be null\n" +	748	"Potential null pointer access: The variable o may be null at this location\n" +
758	"----------\n");	749	"----------\n");
		750	}
		751
		752	// null analysis -- conditional expression
		753	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
		754	// variant with constant condition
		755	public void test0034_conditional_expression_2() {
		756	this.runConformTest(
		757	new String[] {
		758	"X.java",
		759	"public class X {\n" +
		760	" boolean b;\n" +
		761	" void foo() {\n" +
		762	" Object o = false ? null : new Object();\n" +
		763	" o.toString();\n" +
		764	" }\n" +
		765	"}\n"},
		766	"");
		767	}
		768
		769	// null analysis -- conditional expression
		770	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
		771	public void test0034_conditional_expression_3() {
		772	this.runNegativeTest(
		773	new String[] {
		774	"X.java",
		775	"public class X {\n" +
		776	" boolean b;\n" +
		777	" void foo(Object a) {\n" +
		778	" if (a == null) {}\n" +
		779	" Object o = b ? a : new Object();\n" +
		780	" o.toString();\n" +
		781	" }\n" +
		782	"}\n"},
		783	"----------\n" +
		784	"1. ERROR in X.java (at line 6)\n" +
		785	" o.toString();\n" +
		786	" ^\n" +
		787	"Potential null pointer access: The variable o may be null at this location\n" +
		788	"----------\n");
		789	}
		790
		791	// null analysis -- conditional expression
		792	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
		793	// variant with dependency between condition and expression - LocalDeclaration
		794	// TODO(stephan) cannot analyse this flow dependency
		795	public void _test0034_conditional_expression_4() {
		796	this.runConformTest(
		797	new String[] {
		798	"X.java",
		799	"public class X {\n" +
		800	" boolean b;\n" +
		801	" void foo(Object u) {\n" +
		802	" if (u == null) {}\n" + //taint
		803	" Object o = (u == null) ? new Object() : u;\n" +
		804	" o.toString();\n" +
		805	" }\n" +
		806	"}\n"},
		807	"");
		808	}
		809
		810	// null analysis -- conditional expression
		811	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
		812	// variant with dependency between condition and expression - Assignment
		813	// TODO(stephan) cannot analyse this flow dependency
814	public void _test0034_conditional_expression_5() {
815	this.runConformTest(
816	new String[] {
817	"X.java",
818	"public class X {\n" +
819	" boolean b;\n" +
820	" void foo(Object u) {\n" +
821	" if (u == null) {}\n" + //taint
822	" Object o;\n" +
823	" o = (u == null) ? new Object() : u;\n" +
824	" o.toString();\n" +
825	" }\n" +
826	"}\n"},
827	"");
759	}	828	}
760		829
761	// null analysis -- conditional expression	830	// null analysis -- conditional expression

Lines 7-12 Link Here

(-)compiler/org/eclipse/jdt/internal/compiler/ast/ConditionalExpression.java (+13 lines)
7	*	7	*
8	* Contributors:	8	* Contributors:
9	* IBM Corporation - initial API and implementation	9	* IBM Corporation - initial API and implementation
		10	* Stephen Herrmann <stephan@cs.tu-berlin.de> - Contribution for bug 133125
10	*******************************************************************************/	11	*******************************************************************************/
11	package org.eclipse.jdt.internal.compiler.ast;	12	package org.eclipse.jdt.internal.compiler.ast;
12		13
Lines 318-323 Link Here
318	if (ifTrueNullStatus == ifFalseNullStatus) {	319	if (ifTrueNullStatus == ifFalseNullStatus) {
319	return ifTrueNullStatus;	320	return ifTrueNullStatus;
320	}	321	}
		322	// is there a chance of null? -> potentially null
		323	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=133125
		324	switch (ifTrueNullStatus) {
		325	case FlowInfo.NULL:
		326	case FlowInfo.POTENTIALLY_NULL:
		327	return FlowInfo.POTENTIALLY_NULL;
		328	}
		329	switch (ifFalseNullStatus) {
		330	case FlowInfo.NULL:
		331	case FlowInfo.POTENTIALLY_NULL:
		332	return FlowInfo.POTENTIALLY_NULL;
		333	}
321	return FlowInfo.UNKNOWN;	334	return FlowInfo.UNKNOWN;
322	// cannot decide which branch to take, and they disagree	335	// cannot decide which branch to take, and they disagree
323	}	336	}