null argument checker: ignore parameters if method throws exception anyway (IDEA-177823)

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/NullParameterConstraintChecker.java

@@ -50,10 +50,12 @@ import java.util.Set;
 class NullParameterConstraintChecker extends DataFlowRunner {
   private final Set<PsiParameter> myPossiblyViolatedParameters;
   private final Set<PsiParameter> myUsedParameters;
+  private final Set<PsiParameter> myParametersWithSuccessfulExecutionInNotNullState;
 
   private NullParameterConstraintChecker(Collection<PsiParameter> parameters) {
     super(false, true);
     myPossiblyViolatedParameters = new THashSet<>(parameters);
+    myParametersWithSuccessfulExecutionInNotNullState = new THashSet<>();
     myUsedParameters = new THashSet<>();
   }
 
@@ -74,10 +76,14 @@ class NullParameterConstraintChecker extends DataFlowRunner {
     }
     if (nullableParameters.isEmpty()) return PsiParameter.EMPTY_ARRAY;
 
-    final NullParameterConstraintChecker checker = new NullParameterConstraintChecker(nullableParameters);
+    NullParameterConstraintChecker checker = new NullParameterConstraintChecker(nullableParameters);
     checker.analyzeMethod(method.getBody(), new StandardInstructionVisitor());
 
-    return checker.myPossiblyViolatedParameters.stream().filter(checker.myUsedParameters::contains).toArray(PsiParameter[]::new);
+    return checker.myPossiblyViolatedParameters
+      .stream()
+      .filter(checker.myUsedParameters::contains)
+      .filter(checker.myParametersWithSuccessfulExecutionInNotNullState::contains)
+      .toArray(PsiParameter[]::new);
   }
 
   @NotNull
@@ -108,7 +114,10 @@ class NullParameterConstraintChecker extends DataFlowRunner {
       DfaMemoryState memState = instructionState.getMemoryState();
       for (PsiParameter parameter : myPossiblyViolatedParameters.toArray(new PsiParameter[myPossiblyViolatedParameters.size()])) {
         final DfaVariableValue dfaVar = getFactory().getVarFactory().createVariableValue(parameter, false);
-        if (!memState.isNotNull(dfaVar)) {
+        if (memState.isNotNull(dfaVar)) {
+          myParametersWithSuccessfulExecutionInNotNullState.add(parameter);
+        }
+        else {
           myPossiblyViolatedParameters.remove(parameter);
         }
       }

java/java-tests/testData/inspection/dataFlow/fixture/NullArgumentIfMethodExecutionFailsAnyway.java

@@ -0,0 +1,15 @@
+class Test {
+  private static void printAndThrow(String message, Throwable cause) {
+    if (message != null) {
+      System.err.println(message);
+    }
+    if (cause != null) {
+      cause.printStackTrace();
+    }
+    throw new IllegalStateException();
+  }
+  public static void main(String[] args) {
+    printAndThrow("test", <warning descr="Passing 'null' argument to non annotated parameter">null</warning>);
+    printAndThrow(<warning descr="Passing 'null' argument to non annotated parameter">null</warning>, new NullPointerException());
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspection8Test.java

@@ -117,6 +117,10 @@ public class DataFlowInspection8Test extends DataFlowInspectionTestCase {
     doTest();
   }
 
+  public void testNullArgumentIfMethodExecutionFailsAnyway() {
+    doTest();
+  }
+
   public void testNullableArrayComponent() {
     setupCustomAnnotations();
     DataFlowInspection inspection = new DataFlowInspection();