"Remove single lambda parameter declaration": do not suggest when lambda is directly under 'if/when'

#KT-35995 Fixed

idea/src/org/jetbrains/kotlin/idea/quickfix/RemoveSingleLambdaParameterFix.kt

@@ -48,6 +48,9 @@ class RemoveSingleLambdaParameterFix(element: KtParameter) : KotlinQuickFixActio
 
             val lambda = parameterList.parent.parent as? KtLambdaExpression ?: return null
 
+            val lambdaParent = lambda.parent
+            if (lambdaParent is KtWhenEntry || lambdaParent is KtContainerNodeForControlStructureBody) return null
+
             val property = lambda.getStrictParentOfType<KtProperty>()
             if (property != null && property.typeReference == null) return null
 

idea/testData/quickfix/removeSingleLambdaParameter/inIf.kt

@@ -0,0 +1,8 @@
+// "Remove single lambda parameter declaration" "false"
+// ACTION: Add braces to 'if' statement
+// ACTION: Remove explicit lambda parameter types (may break code)
+// ACTION: Rename to _
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        if (i == 1) { <caret>s: String -> true } else { s: String -> false }
+}

idea/testData/quickfix/removeSingleLambdaParameter/inIf2.kt

@@ -0,0 +1,5 @@
+// "Remove single lambda parameter declaration" "true"
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        if (i == 1) { { <caret>s -> true } } else { s -> false }
+}

idea/testData/quickfix/removeSingleLambdaParameter/inIf2.kt.after

@@ -0,0 +1,5 @@
+// "Remove single lambda parameter declaration" "true"
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        if (i == 1) { { true } } else { s -> false }
+}

idea/testData/quickfix/removeSingleLambdaParameter/inWhen.kt

@@ -0,0 +1,11 @@
+// "Remove single lambda parameter declaration" "false"
+// ACTION: Add braces to 'when' entry
+// ACTION: Remove explicit lambda parameter types (may break code)
+// ACTION: Rename to _
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        when (i) {
+            1 -> { <caret>s: String -> true }
+            else -> { s: String -> false }
+        }
+}

idea/testData/quickfix/removeSingleLambdaParameter/inWhen2.kt

@@ -0,0 +1,8 @@
+// "Remove single lambda parameter declaration" "true"
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        when (i) {
+            1 -> { { <caret>s -> true } }
+            else -> { s -> false }
+        }
+}

idea/testData/quickfix/removeSingleLambdaParameter/inWhen2.kt.after

@@ -0,0 +1,8 @@
+// "Remove single lambda parameter declaration" "true"
+fun test(i: Int) {
+    val p: (String) -> Boolean =
+        when (i) {
+            1 -> { { true } }
+            else -> { s -> false }
+        }
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java

@@ -10655,6 +10655,26 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("idea/testData/quickfix/removeSingleLambdaParameter"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), null, true);
         }
 
+        @TestMetadata("inIf.kt")
+        public void testInIf() throws Exception {
+            runTest("idea/testData/quickfix/removeSingleLambdaParameter/inIf.kt");
+        }
+
+        @TestMetadata("inIf2.kt")
+        public void testInIf2() throws Exception {
+            runTest("idea/testData/quickfix/removeSingleLambdaParameter/inIf2.kt");
+        }
+
+        @TestMetadata("inWhen.kt")
+        public void testInWhen() throws Exception {
+            runTest("idea/testData/quickfix/removeSingleLambdaParameter/inWhen.kt");
+        }
+
+        @TestMetadata("inWhen2.kt")
+        public void testInWhen2() throws Exception {
+            runTest("idea/testData/quickfix/removeSingleLambdaParameter/inWhen2.kt");
+        }
+
         @TestMetadata("multiple.kt")
         public void testMultiple() throws Exception {
             runTest("idea/testData/quickfix/removeSingleLambdaParameter/multiple.kt");