add cast: don't unbox for null types (IDEA-193174)

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ArgumentFixerActionFactory.java

@@ -93,7 +93,7 @@ public abstract class ArgumentFixerActionFactory {
           if (parameterType instanceof PsiWildcardType) continue;
           if (!GenericsUtil.isFromExternalTypeLanguage(parameterType)) continue;
           if (suggestedCasts.contains(parameterType.getCanonicalText())) continue;
-          if (exprType instanceof PsiPrimitiveType && parameterType instanceof PsiClassType) {
+          if (TypeConversionUtil.isPrimitiveAndNotNull(exprType) && parameterType instanceof PsiClassType) {
             PsiType unboxedParameterType = PsiPrimitiveType.getUnboxedType(parameterType);
             if (unboxedParameterType != null) {
               parameterType = unboxedParameterType;

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/addTypeCast/afterNullToPrimitiveType.java

@@ -0,0 +1,8 @@
+// "Cast parameter to 'java.lang.Integer'" "true"
+class a {
+   void m(Integer i){}
+   void m(String s) {}
+   void f() {
+       m((Integer) null);
+   }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/addTypeCast/beforeNullToPrimitiveType.java

@@ -0,0 +1,8 @@
+// "Cast parameter to 'java.lang.Integer'" "true"
+class a {
+   void m(Integer i){}
+   void m(String s) {}
+   void f() {
+       m(<caret>null);
+   }
+}