Check that add() method is in fact MutableCollection.add()

#KT-18881 Fixed

idea/src/org/jetbrains/kotlin/idea/intentions/loopToCallChain/result/AddToCollectionTransformation.kt

@@ -17,18 +17,23 @@
 package org.jetbrains.kotlin.idea.intentions.loopToCallChain.result
 
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.VariableDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.unsafeResolveToDescriptor
 import org.jetbrains.kotlin.idea.imports.importableFqName
 import org.jetbrains.kotlin.idea.intentions.loopToCallChain.*
 import org.jetbrains.kotlin.idea.intentions.loopToCallChain.sequence.*
+import org.jetbrains.kotlin.idea.references.resolveMainReferenceToDescriptors
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.getCallNameExpression
 import org.jetbrains.kotlin.renderer.render
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
+import org.jetbrains.kotlin.resolve.descriptorUtil.overriddenTreeUniqueAsSequence
 
 class AddToCollectionTransformation(
         loop: KtForExpression,
@@ -96,8 +101,11 @@ class AddToCollectionTransformation(
             val qualifiedExpression = statement as? KtDotQualifiedExpression ?: return null
             val targetCollection = qualifiedExpression.receiverExpression
             val callExpression = qualifiedExpression.selectorExpression as? KtCallExpression ?: return null
-            if (callExpression.getCallNameExpression()?.getReferencedName() != "add") return null
-            //TODO: check that it's MutableCollection's add
+            val callNameExpression = callExpression.getCallNameExpression() ?: return null
+            if (callNameExpression.getReferencedName() != "add") return null
+            val calleeMethodDescriptors = callNameExpression.resolveMainReferenceToDescriptors()
+            if (calleeMethodDescriptors.none { it.isCollectionAdd() }) return null
+
             val argument = callExpression.valueArguments.singleOrNull() ?: return null
             val argumentValue = argument.getArgumentExpression() ?: return null
 
@@ -204,6 +212,17 @@ class AddToCollectionTransformation(
 
 private fun KtExpression?.isRangeLiteral() = this is KtBinaryExpression && operationToken == KtTokens.RANGE
 
+private fun DeclarationDescriptor.isCollectionAdd(): Boolean {
+    if ((containingDeclaration as? ClassDescriptor)?.fqNameSafe == KotlinBuiltIns.FQ_NAMES.mutableCollection) {
+        return true
+    }
+
+    val overrides = (this as? CallableDescriptor)?.overriddenTreeUniqueAsSequence(true) ?: return false
+    return overrides.any {
+        (it.containingDeclaration as? ClassDescriptor)?.fqNameSafe == KotlinBuiltIns.FQ_NAMES.mutableCollection
+    }
+}
+
 class FilterToTransformation private constructor(
         loop: KtForExpression,
         private val inputVariable: KtCallableDeclaration,

idea/testData/intentions/loopToCallChain/toCollection/KT18881.kt

@@ -0,0 +1,14 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+// IS_APPLICABLE_2: false
+data class Node(private val data: MutableList<String>) {
+    fun add(word: String) {
+        data.add(word)
+    }
+}
+
+fun foo(node: Node, words: List<String>) {
+    <caret>for (word in words) {
+        node.add(word)
+    }
+}

idea/tests/org/jetbrains/kotlin/idea/intentions/IntentionTest2Generated.java

@@ -1550,6 +1550,12 @@ public class IntentionTest2Generated extends AbstractIntentionTest2 {
             doTest(fileName);
         }
 
+        @TestMetadata("KT18881.kt")
+        public void testKT18881() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/toCollection/KT18881.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("resultCollectionUsedInsideLoop.kt")
         public void testResultCollectionUsedInsideLoop() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/toCollection/resultCollectionUsedInsideLoop.kt");

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

@@ -11461,6 +11461,12 @@ public class IntentionTestGenerated extends AbstractIntentionTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("KT18881.kt")
+            public void testKT18881() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/toCollection/KT18881.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("resultCollectionUsedInsideLoop.kt")
             public void testResultCollectionUsedInsideLoop() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("idea/testData/intentions/loopToCallChain/toCollection/resultCollectionUsedInsideLoop.kt");