IterateExpressionIntention: checking for name conflicts

idea/idea-core/src/org/jetbrains/kotlin/idea/core/NameValidators.kt

@@ -51,10 +51,17 @@ public class CollectingNameValidator @jvmOverloads constructor(
 }
 
 public class NewDeclarationNameValidator(
-        private val container: PsiElement,
-        private val anchor: PsiElement?,
+        private val visibleDeclarationsContext: JetElement?,
+        private val checkDeclarationsIn: Sequence<PsiElement>,
         private val target: NewDeclarationNameValidator.Target
 ) : (String) -> Boolean {
+
+    public constructor(container: PsiElement, anchor: PsiElement?, target: NewDeclarationNameValidator.Target)
+        : this(
+            (anchor ?: container).parentsWithSelf.firstIsInstanceOrNull<JetElement>(),
+            anchor?.siblings() ?: container.allChildren,
+            target)
+
     public enum class Target {
         VARIABLES,
         FUNCTIONS_AND_CLASSES
@@ -63,13 +70,13 @@ public class NewDeclarationNameValidator(
     override fun invoke(name: String): Boolean {
         val identifier = Name.identifier(name)
 
-        val scopeContext = (anchor ?: container).parentsWithSelf.firstIsInstanceOrNull<JetElement>() ?: return true
-        val bindingContext = scopeContext.analyze(BodyResolveMode.PARTIAL_FOR_COMPLETION)
-        val resolutionScope = scopeContext.getResolutionScope(bindingContext, scopeContext.getResolutionFacade())
-        if (resolutionScope.hasConflict(identifier)) return false
+        if (visibleDeclarationsContext != null) {
+            val bindingContext = visibleDeclarationsContext.analyze(BodyResolveMode.PARTIAL_FOR_COMPLETION)
+            val resolutionScope = visibleDeclarationsContext.getResolutionScope(bindingContext, visibleDeclarationsContext.getResolutionFacade())
+            if (resolutionScope.hasConflict(identifier)) return false
+        }
 
-        val elementsToCheck = anchor?.siblings() ?: container.allChildren
-        return elementsToCheck.none {
+        return checkDeclarationsIn.none {
             it.findDescendantOfType<JetNamedDeclaration> { it.isConflicting(identifier) } != null
         }
     }

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

@@ -25,9 +25,11 @@ import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
 import org.jetbrains.kotlin.idea.core.IterableTypesDetector
 import org.jetbrains.kotlin.idea.core.KotlinNameSuggester
+import org.jetbrains.kotlin.idea.core.NewDeclarationNameValidator
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.siblings
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import org.jetbrains.kotlin.types.JetType
@@ -57,8 +59,8 @@ public class IterateExpressionIntention : JetSelfTargetingIntention<JetExpressio
         //TODO: multi-declaration (when?)
 
         val elementType = data(element)!!.elementType
-        //TODO: name validation
-        val names = KotlinNameSuggester.suggestIterationVariableNames(element, elementType, { true }, "e")
+        val nameValidator = NewDeclarationNameValidator(element, element.siblings(), NewDeclarationNameValidator.Target.VARIABLES)
+        val names = KotlinNameSuggester.suggestIterationVariableNames(element, elementType, nameValidator, "e")
 
         var forExpression = JetPsiFactory(element).createExpressionByPattern("for($0 in $1) {\nx\n}", names.first(), element) as JetForExpression
         forExpression = element.replaced(forExpression)

idea/src/org/jetbrains/kotlin/idea/refactoring/introduce/introduceParameter/KotlinIntroduceParameterHandler.kt

@@ -234,7 +234,7 @@ public open class KotlinIntroduceParameterHandler(
                        is JetClass -> targetParent.getBody()
                        else -> null
                    } ?: throw AssertionError("Body element is not found: ${targetParent.getElementTextWithContext()}")
-        val nameValidator = NewDeclarationNameValidator(body, null, NewDeclarationNameValidator.Target.VARIABLES)
+        val nameValidator = NewDeclarationNameValidator(body, sequenceOf(body), NewDeclarationNameValidator.Target.VARIABLES)
         val suggestedNames = KotlinNameSuggester.suggestNamesByType(replacementType, nameValidator, "p")
 
         val parametersUsages = findInternalUsagesOfParametersAndReceiver(targetParent, functionDescriptor)

idea/testData/intentions/iterateExpression/noNameConflict.kt

@@ -0,0 +1,9 @@
+fun foo(names: List<String>, name: String) {
+    if (name == "") {
+        val name2 = ""
+    }
+
+    names<caret>
+
+    val name1 = ""
+}

idea/testData/intentions/iterateExpression/noNameConflict.kt.after

@@ -0,0 +1,11 @@
+fun foo(names: List<String>, name: String) {
+    if (name == "") {
+        val name2 = ""
+    }
+
+    for (name2 in names) {
+        <caret>
+    }
+
+    val name1 = ""
+}

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

@@ -5241,6 +5241,12 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
             doTest(fileName);
         }
 
+        @TestMetadata("noNameConflict.kt")
+        public void testNoNameConflict() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("idea/testData/intentions/iterateExpression/noNameConflict.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("simple.kt")
         public void testSimple() throws Exception {
             String fileName = JetTestUtils.navigationMetadata("idea/testData/intentions/iterateExpression/simple.kt");