Introduce Parameter: Fix parameter name validation

Respect existing parameter names and fix some exceptions

 #KT-19439 Fixed
 #KT-20402 Fixed
 #KT-20403 Fixed

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

@@ -248,11 +248,13 @@ open class KotlinIntroduceParameterHandler(
         val replacementType = expressionType.approximateWithResolvableType(targetParent.getResolutionScope(context, targetParent.getResolutionFacade()), false)
 
         val body = when (targetParent) {
-                       is KtFunction -> targetParent.bodyExpression
-                       is KtClass -> targetParent.getBody()
-                       else -> null
-                   } ?: throw AssertionError("Body element is not found: ${targetParent.getElementTextWithContext()}")
-        val nameValidator = NewDeclarationNameValidator(body, sequenceOf(body), NewDeclarationNameValidator.Target.VARIABLES)
+            is KtFunction -> targetParent.bodyExpression
+            is KtClass -> targetParent.getBody()
+            else -> null
+        }
+        val bodyValidator: ((String) -> Boolean)? =
+                body?.let { NewDeclarationNameValidator(it, sequenceOf(it), NewDeclarationNameValidator.Target.VARIABLES) }
+        val nameValidator = CollectingNameValidator(targetParent.getValueParameters().mapNotNull { it.name }, bodyValidator ?: { true })
 
         val suggestedNames = SmartList<String>().apply {
             if (physicalExpression is KtProperty && !ApplicationManager.getApplication().isUnitTestMode) {
@@ -271,7 +273,7 @@ open class KotlinIntroduceParameterHandler(
         }
         else {
             expression.toRange()
-                    .match(body, KotlinPsiUnifier.DEFAULT)
+                    .match(targetParent, KotlinPsiUnifier.DEFAULT)
                     .filterNot {
                         val textRange = it.range.getPhysicalTextRange()
                         forbiddenRanges.any { it.intersects(textRange) }

idea/testData/refactoring/introduceParameter/avoidClassDuplicatingParameters.kt

@@ -0,0 +1,3 @@
+class Foo(i: Int) {
+    val x = <selection>1 + 2</selection> + 3
+}

idea/testData/refactoring/introduceParameter/avoidClassDuplicatingParameters.kt.after

@@ -0,0 +1,3 @@
+class Foo(i: Int, i1: Int = 1 + 2) {
+    val x = i1 + 3
+}

idea/testData/refactoring/introduceParameter/avoidFunDuplicatingParameters.kt

@@ -0,0 +1,3 @@
+fun foo(i: Int) {
+    val x = <selection>1 + 2</selection> + 3
+}

idea/testData/refactoring/introduceParameter/avoidFunDuplicatingParameters.kt.after

@@ -0,0 +1,3 @@
+fun foo(i: Int, i1: Int = 1 + 2) {
+    val x = i1 + 3
+}

idea/testData/refactoring/introduceParameter/superCallArgument.kt

@@ -0,0 +1,9 @@
+class A : B({ "${<selection>C.c</selection>}" })
+
+class C() {
+    companion object {
+        val c = 23
+    }
+}
+
+open class B(param: () -> String)

idea/testData/refactoring/introduceParameter/superCallArgument.kt.after

@@ -0,0 +1,9 @@
+class A(val i: Int = C.c) : B({ "$i" })
+
+class C() {
+    companion object {
+        val c = 23
+    }
+}
+
+open class B(param: () -> String)

idea/tests/org/jetbrains/kotlin/idea/refactoring/introduce/ExtractionTestGenerated.java

@@ -3356,6 +3356,18 @@ public class ExtractionTestGenerated extends AbstractExtractionTest {
             doIntroduceSimpleParameterTest(fileName);
         }
 
+        @TestMetadata("avoidClassDuplicatingParameters.kt")
+        public void testAvoidClassDuplicatingParameters() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/introduceParameter/avoidClassDuplicatingParameters.kt");
+            doIntroduceSimpleParameterTest(fileName);
+        }
+
+        @TestMetadata("avoidFunDuplicatingParameters.kt")
+        public void testAvoidFunDuplicatingParameters() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/introduceParameter/avoidFunDuplicatingParameters.kt");
+            doIntroduceSimpleParameterTest(fileName);
+        }
+
         @TestMetadata("classInAnonymousInitializer.kt")
         public void testClassInAnonymousInitializer() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/introduceParameter/classInAnonymousInitializer.kt");
@@ -3596,6 +3608,12 @@ public class ExtractionTestGenerated extends AbstractExtractionTest {
             doIntroduceSimpleParameterTest(fileName);
         }
 
+        @TestMetadata("superCallArgument.kt")
+        public void testSuperCallArgument() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/introduceParameter/superCallArgument.kt");
+            doIntroduceSimpleParameterTest(fileName);
+        }
+
         @TestMetadata("throw.kt")
         public void testThrow() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/introduceParameter/throw.kt");