"Replace 'if' with elvis operator": Don't suggest on nullable type check #KT-25886 Fixed

idea/src/org/jetbrains/kotlin/idea/intentions/FoldInitializerAndIfToElvisIntention.kt

@@ -121,6 +121,7 @@ class FoldInitializerAndIfToElvisIntention : SelfTargetingRangeIntention<KtIfExp
             }
             is KtIsExpression -> {
                 if (!operationExpression.isNegated) return null
+                if (operationExpression.typeReference?.typeElement is KtNullableType) return null
                 operationExpression.leftHandSide
             }
             else -> return null

idea/testData/intentions/foldInitializerAndIfToElvis/NotIsNullableType.kt

@@ -0,0 +1,8 @@
+// IS_APPLICABLE: false
+fun test(): String {
+    val foo = foo()
+    <caret>if (foo !is String?) return "0"
+    return "1"
+}
+
+fun foo(): Any? = null

idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTestGenerated.java

@@ -8436,6 +8436,11 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             runTest("idea/testData/intentions/foldInitializerAndIfToElvis/NotIs.kt");
         }
 
+        @TestMetadata("NotIsNullableType.kt")
+        public void testNotIsNullableType() throws Exception {
+            runTest("idea/testData/intentions/foldInitializerAndIfToElvis/NotIsNullableType.kt");
+        }
+
         @TestMetadata("OtherVar1.kt")
         public void testOtherVar1() throws Exception {
             runTest("idea/testData/intentions/foldInitializerAndIfToElvis/OtherVar1.kt");