Simplify for intention: apply name validator to prevent conflicts

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

@@ -25,6 +25,8 @@ import com.intellij.util.Query
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.analyzeFullyAndGetResult
+import org.jetbrains.kotlin.idea.core.KotlinNameSuggester
+import org.jetbrains.kotlin.idea.core.NewDeclarationNameValidator
 import org.jetbrains.kotlin.idea.inspections.IntentionBasedInspection
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation
 import org.jetbrains.kotlin.lexer.KtTokens
@@ -34,7 +36,7 @@ import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
-import org.jetbrains.kotlin.resolve.scopes.DescriptorKindFilter
+import java.util.*
 import kotlin.collections.forEach
 
 class SimplifyForInspection : IntentionBasedInspection<KtForExpression>(SimplifyForIntention())
@@ -51,13 +53,18 @@ class SimplifyForIntention : SelfTargetingRangeIntention<KtForExpression>(
         val loopParameter = element.loopParameter ?: return
 
         val factory = KtPsiFactory(element)
-        loopParameter.replace(factory.createDestructuringDeclarationInFor("(${usagesToRemove.joinToString { it.name!! }})"))
+        val validator = NewDeclarationNameValidator(element.parent, element, NewDeclarationNameValidator.Target.VARIABLES,
+                                                    usagesToRemove.map { it.properties }.flatten())
+        val names = ArrayList<String>()
         usagesToRemove.forEach { p ->
+            val name = KotlinNameSuggester.suggestNameByName(p.name!!, validator)
             p.properties.firstOrNull()?.delete()
             p.usersToReplace.forEach {
-                it.replace(factory.createExpression(p.name!!))
+                it.replace(factory.createExpression(name))
             }
+            names.add(name)
         }
+        loopParameter.replace(factory.createDestructuringDeclarationInFor("(${names.joinToString()})"))
 
         if (removeSelectorInLoopRange && loopRange is KtDotQualifiedExpression) {
             loopRange.replace(loopRange.receiverExpression)

idea/testData/intentions/iterationOverMap/DataClassNameConflict.kt

@@ -0,0 +1,12 @@
+// WITH_RUNTIME
+
+data class XY(val x: Int, val y: Int)
+
+fun foo(list: List<XY>) {
+    val y = list.size
+    for (<caret>element in list) {
+        val x = element.x + element.y
+        println(x)
+        println(y)
+    }
+}

idea/testData/intentions/iterationOverMap/DataClassNameConflict.kt.after

@@ -0,0 +1,12 @@
+// WITH_RUNTIME
+
+data class XY(val x: Int, val y: Int)
+
+fun foo(list: List<XY>) {
+    val y = list.size
+    for ((x1, y1) in list) {
+        val x = x1 + y1
+        println(x)
+        println(y)
+    }
+}

idea/testData/intentions/iterationOverMap/inspectionData/expected.xml

@@ -167,4 +167,12 @@
         <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">'for' that can be simplified using destructing declaration</problem_class>
         <description>Simplify 'for' using destructing declaration</description>
     </problem>
+    <problem>
+        <file>DataClassNameConflict.kt</file>
+        <line>7</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/DataClassNameConflict.kt" />
+        <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">'for' that can be simplified using destructing declaration</problem_class>
+        <description>Simplify 'for' using destructing declaration</description>
+    </problem>
 </problems>

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

@@ -6555,6 +6555,12 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             doTest(fileName);
         }
 
+        @TestMetadata("DataClassNameConflict.kt")
+        public void testDataClassNameConflict() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/iterationOverMap/DataClassNameConflict.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("DataClassNoVariablesInside.kt")
         public void testDataClassNoVariablesInside() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/iterationOverMap/DataClassNoVariablesInside.kt");