[Kotlin] Fixed for loop declarations leaking to outer scope when using PSI-only based completion

KTIJ-19995

GitOrigin-RevId: e01effa55285da3258b029ce4be963a7a040db2e

plugins/kotlin/completion/impl-shared/src/org/jetbrains/kotlin/idea/completion/implCommon/PsiTreeCompletion.kt

@@ -238,6 +238,10 @@ class PsiTreeCompletion {
             return super.visitClassBody(classBody, data.registerSubScope(classBody.textRange, scopeType))
         }
 
+        override fun visitForExpression(expression: KtForExpression, data: LookupScope): Void? {
+            return super.visitForExpression(expression, data.registerSubScope(expression.textRange, ScopeType.LOCAL))
+        }
+
         override fun visitNamedFunction(function: KtNamedFunction, data: LookupScope): Void? {
             // We handle this declaration separately because it needs to open a new scope for the
             // function parameters, so they do not leak to the outside scope.

plugins/kotlin/completion/testData/dumb/ForLoopDeclarationInBody.kt

@@ -0,0 +1,8 @@
+fun test() {
+    for (prefixTest in test) {
+        val a = prefix<caret>
+    }
+}
+
+// EXIST: prefixTest
+// NOTHING_ELSE

plugins/kotlin/completion/testData/dumb/ForLoopDeclarationShouldNotLeak.kt

@@ -0,0 +1,9 @@
+fun test() {
+    for (prefixTest in test) {
+
+    }
+    val a = prefix<caret>
+}
+
+// ABSENT: prefixTest
+// NOTHING_ELSE

plugins/kotlin/completion/tests-k1/test/org/jetbrains/kotlin/idea/completion/test/DumbCompletionTestGenerated.java

@@ -118,6 +118,16 @@ public class DumbCompletionTestGenerated extends AbstractDumbCompletionTest {
         runTest("../testData/dumb/ExtensionProperty.kt");
     }
 
+    @TestMetadata("ForLoopDeclarationInBody.kt")
+    public void testForLoopDeclarationInBody() throws Exception {
+        runTest("../testData/dumb/ForLoopDeclarationInBody.kt");
+    }
+
+    @TestMetadata("ForLoopDeclarationShouldNotLeak.kt")
+    public void testForLoopDeclarationShouldNotLeak() throws Exception {
+        runTest("../testData/dumb/ForLoopDeclarationShouldNotLeak.kt");
+    }
+
     @TestMetadata("Function.kt")
     public void testFunction() throws Exception {
         runTest("../testData/dumb/Function.kt");

plugins/kotlin/fir/tests/test/org/jetbrains/kotlin/idea/fir/completion/FirDumbCompletionTestGenerated.java

@@ -118,6 +118,16 @@ public class FirDumbCompletionTestGenerated extends AbstractFirDumbCompletionTes
         runTest("../../completion/testData/dumb/ExtensionProperty.kt");
     }
 
+    @TestMetadata("ForLoopDeclarationInBody.kt")
+    public void testForLoopDeclarationInBody() throws Exception {
+        runTest("../../completion/testData/dumb/ForLoopDeclarationInBody.kt");
+    }
+
+    @TestMetadata("ForLoopDeclarationShouldNotLeak.kt")
+    public void testForLoopDeclarationShouldNotLeak() throws Exception {
+        runTest("../../completion/testData/dumb/ForLoopDeclarationShouldNotLeak.kt");
+    }
+
     @TestMetadata("Function.kt")
     public void testFunction() throws Exception {
         runTest("../../completion/testData/dumb/Function.kt");