Fix quality flaw: fix coverage on conditions when flow message target…

…s ternary (#1491)
SonarSource · May 24, 2017 · b4d6f2a · b4d6f2a
1 parent 662682d
commit b4d6f2a
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Showing 2 changed files with 25 additions and 4 deletions.
diff --git a/java-frontend/src/main/java/org/sonar/java/se/FlowComputation.java b/java-frontend/src/main/java/org/sonar/java/se/FlowComputation.java
@@ -385,8 +385,7 @@ List<JavaFileScannerContext.Location> flowFromLearnedAssociation(LearnedAssociat
         for (Constraint constraint : constraints) {
           String symbolName = learnedAssociation.symbol().name();
           String msg;
-          if ((ObjectConstraint.NULL == constraint && assigningNullFromTernary(node))
-            || (assigningFromMethodInvocation(node) && assignedFromYieldWithUncertainResult(constraint, node))) {
+          if (assigningNullFromTernary(node) || (assigningFromMethodInvocation(node) && assignedFromYieldWithUncertainResult(constraint, node))) {
             msg = IMPLIES_CAN_BE_MSG;
           } else {
             msg = IMPLIES_IS_MSG;
@@ -443,7 +442,7 @@ private boolean isTernaryWithNullBranch(@Nullable ExpressionTree expressionTree)
       ExpressionTree expr = ExpressionUtils.skipParentheses(expressionTree);
       if (expr.is(Tree.Kind.CONDITIONAL_EXPRESSION)) {
         ConditionalExpressionTree cet = (ConditionalExpressionTree) expr;
-        return ExpressionUtils.isNullLiteral(cet.trueExpression()) || ExpressionUtils.isNullLiteral(cet.falseExpression());
+        return ExpressionUtils.isNullLiteral(cet.trueExpression()) ^ ExpressionUtils.isNullLiteral(cet.falseExpression());
       }
       return false;
     }

diff --git a/java-frontend/src/test/files/se/FlowMessagesBranch.java b/java-frontend/src/test/files/se/FlowMessagesBranch.java
@@ -1,4 +1,4 @@
-abstract class A {
+class A {
 
   void foo(Object a, Object b) {
     if (a == null       // flow@npe1 {{Implies 'a' can be null.}}
@@ -23,4 +23,26 @@ void qix(Object a) {
     o.toString(); // flow@npe3 {{'o' is dereferenced.}}
   }
 
+  void gul(Object a) {
+    Object o = a != null ? null : null; // flow@npe4 {{Implies 'o' is null.}}
+    // Noncompliant@+1 [[flows=npe4]] {{A "NullPointerException" could be thrown; "o" is nullable here.}}
+    o.toString(); // flow@npe4 {{'o' is dereferenced.}}
+  }
+
+  void dag(Object a) {
+    Object o = a == null ? null : a.toString(); // flow@npe5 {{Implies 'o' can be null.}}
+    // Noncompliant@+1 [[flows=npe5]] {{A "NullPointerException" could be thrown; "o" is nullable here.}}
+    o.toString(); // flow@npe5 {{'o' is dereferenced.}}
+  }
+
+  void cro(Object a) {
+    Object o = a != null ? a.toString() : foo(); // flow@npe6 {{'foo()' returns null.}} flow@npe6 {{Implies 'o' is null.}}
+    // Noncompliant@+1 [[flows=npe6]] {{A "NullPointerException" could be thrown; "o" is nullable here.}}
+    o.toString(); // flow@npe6 {{'o' is dereferenced.}}
+  }
+
+  static Object foo() {
+    return null;
+  }
+
 }