Invert if condition intention: 'isEmpty' <-> 'isNotEmpty'

#KT-34593 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/ReplaceNegatedIsEmptyWithIsNotEmptyInspection.kt

@@ -24,20 +24,10 @@ import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
 class ReplaceNegatedIsEmptyWithIsNotEmptyInspection : AbstractKotlinInspection() {
     override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
         return qualifiedExpressionVisitor(fun(expression) {
-            val callExpression = expression.callExpression ?: return
+            if (expression.getWrappingPrefixExpressionIfAny()?.operationToken != KtTokens.EXCL) return
-            val calleeExpression = callExpression.calleeExpression ?: return
+            val calleeExpression = expression.callExpression?.calleeExpression ?: return
-            val calleeText = calleeExpression.text
+            val from = calleeExpression.text
-            val isEmptyCall = calleeText == "isEmpty"
+            val to = expression.invertSelectorFunction()?.callExpression?.calleeExpression?.text ?: return
-            val isNotEmptyCall = calleeText == "isNotEmpty"
-            if (!isEmptyCall && !isNotEmptyCall) return
-
-            val prefixExpression = expression.getWrappingPrefixExpressionIfAny() ?: return
-            if (prefixExpression.operationToken != KtTokens.EXCL) return
-
-            if (isEmptyCall && isEmptyFunctions.none { callExpression.isCalling(FqName(it)) }
-                || isNotEmptyCall && isNotEmptyFunctions.none { callExpression.isCalling(FqName(it)) }) return
-
-            val (from, to) = if (isEmptyCall) "isEmpty" to "isNotEmpty" else "isNotEmpty" to "isEmpty"
             holder.registerProblem(
                 calleeExpression,
                 "Replace negated '$from' with '$to'",
@@ -46,6 +36,25 @@ class ReplaceNegatedIsEmptyWithIsNotEmptyInspection : AbstractKotlinInspection()
             )
         })
     }
+
+    companion object {
+        fun KtQualifiedExpression.invertSelectorFunction(): KtQualifiedExpression? {
+            val callExpression = this.callExpression ?: return null
+            val calleeExpression = callExpression.calleeExpression ?: return null
+            val calleeText = calleeExpression.text
+            val isEmptyCall = calleeText == "isEmpty"
+            val isNotEmptyCall = calleeText == "isNotEmpty"
+            if (!isEmptyCall && !isNotEmptyCall) return null
+            if (isEmptyCall && isEmptyFunctions.none { callExpression.isCalling(FqName(it)) }
+                || isNotEmptyCall && isNotEmptyFunctions.none { callExpression.isCalling(FqName(it)) }) return null
+            val to = if (isEmptyCall) "isNotEmpty" else "isEmpty"
+            return KtPsiFactory(this).createExpressionByPattern(
+                "$0.$to()",
+                this.receiverExpression,
+                reformat = false
+            ) as? KtQualifiedExpression
+        }
+    }
 }
 
 class ReplaceNegatedIsEmptyWithIsNotEmptyQuickFix(private val from: String, private val to: String) : LocalQuickFix {

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

@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.core.moveCaret
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.core.unblockDocument
+import org.jetbrains.kotlin.idea.inspections.ReplaceNegatedIsEmptyWithIsNotEmptyInspection.Companion.invertSelectorFunction
 import org.jetbrains.kotlin.idea.refactoring.getLineNumber
 import org.jetbrains.kotlin.idea.util.CommentSaver
 import org.jetbrains.kotlin.idea.util.psi.patternMatching.matches
@@ -39,7 +40,8 @@ class InvertIfConditionIntention : SelfTargetingIntention<KtIfExpression>(KtIfEx
             element.nextEolCommentOnSameLine()?.delete()
         }
 
-        val newCondition = element.condition!!.negate()
+        val condition = element.condition!!
+        val newCondition = (condition as? KtQualifiedExpression)?.invertSelectorFunction() ?: condition.negate()
 
         val newIf = handleSpecialCases(element, newCondition) ?: handleStandardCase(element, newCondition)
 

idea/testData/intentions/invertIfCondition/isEmpty.kt

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isEmpty()) {
+        foo(1)
+    } else {
+        foo(2)
+    }
+}

idea/testData/intentions/invertIfCondition/isEmpty.kt.after

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isNotEmpty()) {
+        foo(2)
+    } else {
+        foo(1)
+    }
+}

idea/testData/intentions/invertIfCondition/isNotEmpty.kt

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isNotEmpty()) {
+        foo(1)
+    } else {
+        foo(2)
+    }
+}

idea/testData/intentions/invertIfCondition/isNotEmpty.kt.after

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isEmpty()) {
+        foo(2)
+    } else {
+        foo(1)
+    }
+}

idea/testData/intentions/invertIfCondition/negatedIsEmpty.kt

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (!s.isEmpty()) {
+        foo(1)
+    } else {
+        foo(2)
+    }
+}

idea/testData/intentions/invertIfCondition/negatedIsEmpty.kt.after

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isEmpty()) {
+        foo(2)
+    } else {
+        foo(1)
+    }
+}

idea/testData/intentions/invertIfCondition/negatedIsNotEmpty.kt

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (!s.isNotEmpty()) {
+        foo(1)
+    } else {
+        foo(2)
+    }
+}

idea/testData/intentions/invertIfCondition/negatedIsNotEmpty.kt.after

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+fun foo(i: Int) {}
+
+fun test(s: String) {
+    <caret>if (s.isNotEmpty()) {
+        foo(2)
+    } else {
+        foo(1)
+    }
+}

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

@@ -9494,6 +9494,16 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             runTest("idea/testData/intentions/invertIfCondition/is.kt");
         }
 
+        @TestMetadata("isEmpty.kt")
+        public void testIsEmpty() throws Exception {
+            runTest("idea/testData/intentions/invertIfCondition/isEmpty.kt");
+        }
+
+        @TestMetadata("isNotEmpty.kt")
+        public void testIsNotEmpty() throws Exception {
+            runTest("idea/testData/intentions/invertIfCondition/isNotEmpty.kt");
+        }
+
         @TestMetadata("lambdaNonLocalAndLocalReturn.kt")
         public void testLambdaNonLocalAndLocalReturn() throws Exception {
             runTest("idea/testData/intentions/invertIfCondition/lambdaNonLocalAndLocalReturn.kt");
@@ -9559,6 +9569,16 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             runTest("idea/testData/intentions/invertIfCondition/negatedExpression.kt");
         }
 
+        @TestMetadata("negatedIsEmpty.kt")
+        public void testNegatedIsEmpty() throws Exception {
+            runTest("idea/testData/intentions/invertIfCondition/negatedIsEmpty.kt");
+        }
+
+        @TestMetadata("negatedIsNotEmpty.kt")
+        public void testNegatedIsNotEmpty() throws Exception {
+            runTest("idea/testData/intentions/invertIfCondition/negatedIsNotEmpty.kt");
+        }
+
         @TestMetadata("nestedIfWithReturn.kt")
         public void testNestedIfWithReturn() throws Exception {
             runTest("idea/testData/intentions/invertIfCondition/nestedIfWithReturn.kt");