IDEA-175510 "Constant conditions & exceptions" inspection provides non-sensical quick fix in some cases

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

@@ -293,6 +293,7 @@ public class DataFlowInspectionBase extends BaseJavaBatchLocalInspectionTool {
   }
 
   private static boolean isNullLiteral(PsiExpression qualifier) {
+    if (qualifier instanceof PsiTypeCastExpression) return isNullLiteral(((PsiTypeCastExpression)qualifier).getOperand());
     return qualifier instanceof PsiLiteralExpression && ((PsiLiteralExpression)qualifier).getValue() == null;
   }
 

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

@@ -0,0 +1,9 @@
+import org.jetbrains.annotations.NotNull;
+
+class Foo {
+  void main() {
+    foo(<warning descr="Argument '(String) null' might be null">(String) nu<caret>ll</warning>);
+  }
+
+  static void foo(@NotNull String s) {}
+}

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

@@ -23,6 +23,7 @@ import com.intellij.psi.PsiField;
 import com.intellij.testFramework.LightProjectDescriptor;
 import com.intellij.testFramework.PlatformTestUtil;
 import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture;
+import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 
 /**
@@ -524,4 +525,9 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
     doTest();
   }
 
+  public void testNoNonSensicalFixesOnCastedNull() {
+    doTest();
+    assertEmpty(ContainerUtil.findAll(myFixture.getAvailableIntentions(), i -> i.getText().contains("null")));
+  }
+
 }