Improve: add more cases for MoveVariableDeclarationIntoWhen

#KT-30499 Fixed

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

@@ -60,10 +60,26 @@ private fun KtProperty.action(element: KtElement): Action = when (val elementUsa
 }
 
 private fun KtWhenExpression.findDeclarationNear(): KtProperty? {
-    val previousProperty = previousStatement() as? KtProperty ?: return null
+    val previousProperty = previousStatement() as? KtProperty
+        ?: previousPropertyFromParent()
+        ?: return null
     return previousProperty.takeIf { !it.isVar && it.hasInitializer() && it.nameIdentifier?.text == subjectExpression?.text }
 }
 
+private tailrec fun KtExpression.previousPropertyFromParent(): KtProperty? {
+    val parentExpression = parent as? KtExpression ?: return null
+    if (this != when (parentExpression) {
+            is KtProperty -> parentExpression.initializer
+            is KtReturnExpression -> parentExpression.returnedExpression
+            is KtBinaryExpression -> parentExpression.left
+            is KtUnaryExpression -> parentExpression.baseExpression
+            else -> null
+        }
+    ) return null
+
+    return parentExpression.previousStatement() as? KtProperty ?: parentExpression.previousPropertyFromParent()
+}
+
 private class VariableDeclarationIntoWhenFix(
     private val actionName: String,
     private val subjectExpressionPointer: SmartPsiElementPointer<KtExpression>,

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inBinaryExpression.kt

@@ -0,0 +1,9 @@
+fun test() = true
+
+fun foo(): Int {
+    val a<caret> = test()
+    return when (a) {
+        true -> 42
+        else -> null
+    } ?: 55
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inBinaryExpression.kt.after

@@ -0,0 +1,8 @@
+fun test() = true
+
+fun foo(): Int {
+    return when (test()) {
+        true -> 42
+        else -> null
+    } ?: 55
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inProperty.kt

@@ -0,0 +1,9 @@
+fun test() = 42
+
+fun foo() {
+    val a<caret> = test()
+    val b = when (a) {
+        1 -> a
+        else -> 24
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inProperty.kt.after

@@ -0,0 +1,8 @@
+fun test() = 42
+
+fun foo() {
+    val b = when (val a = test()) {
+        1 -> a
+        else -> 24
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inReturnExpression.kt

@@ -0,0 +1,9 @@
+fun test() = 42
+
+fun foo(): Int {
+    val a<caret> = test()
+    return when (a) {
+        1 -> a
+        else -> 24
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inReturnExpression.kt.after

@@ -0,0 +1,8 @@
+fun test() = 42
+
+fun foo(): Int {
+    return when (val a = test()) {
+        1 -> a
+        else -> 24
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inUnaryAndProperty.kt

@@ -0,0 +1,9 @@
+fun test() = true
+
+fun foo() {
+    val a<caret> = test()
+    val b = !when (a) {
+        true -> true
+        else -> false
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inUnaryAndProperty.kt.after

@@ -0,0 +1,8 @@
+fun test() = true
+
+fun foo() {
+    val b = !when (test()) {
+        true -> true
+        else -> false
+    }
+}

idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/notApplicableInBinaryExpression.kt

@@ -0,0 +1,10 @@
+// PROBLEM: none
+fun test() = true
+
+fun foo(): Int {
+    val a<caret> = test()
+    return null ?: when (a) {
+        true -> 42
+        else -> 5
+    }
+}

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -4357,6 +4357,31 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("inBinaryExpression.kt")
+        public void testInBinaryExpression() throws Exception {
+            runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inBinaryExpression.kt");
+        }
+
+        @TestMetadata("inProperty.kt")
+        public void testInProperty() throws Exception {
+            runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inProperty.kt");
+        }
+
+        @TestMetadata("inReturnExpression.kt")
+        public void testInReturnExpression() throws Exception {
+            runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inReturnExpression.kt");
+        }
+
+        @TestMetadata("inUnaryAndProperty.kt")
+        public void testInUnaryAndProperty() throws Exception {
+            runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/inUnaryAndProperty.kt");
+        }
+
+        @TestMetadata("notApplicableInBinaryExpression.kt")
+        public void testNotApplicableInBinaryExpression() throws Exception {
+            runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/notApplicableInBinaryExpression.kt");
+        }
+
         @TestMetadata("notApplicableOtherName.kt")
         public void testNotApplicableOtherName() throws Exception {
             runTest("idea/testData/inspectionsLocal/moveVariableDeclarationIntoWhen/notApplicableOtherName.kt");