JS: don't resolve unused temporaries

js/js.inliner/src/org/jetbrains/kotlin/js/inline/clean/resolveTemporaryNames.kt

@@ -39,12 +39,14 @@ import com.google.dart.compiler.backend.js.ast.metadata.suspendObjectRef
 import org.jetbrains.kotlin.js.inline.util.collectReferencedTemporaryNames
 
 fun JsNode.resolveTemporaryNames() {
+    val allNames = collectReferencedTemporaryNames(this)
+
     val scopeTree = ScopeCollector().let {
         it.accept(this)
         it.scopeTree
     }
 
-    val renamings = scopeTree.resolveNames()
+    val renamings = scopeTree.resolveNames(allNames)
     accept(object : RecursiveJsVisitor() {
         override fun visitElement(node: JsNode) {
             super.visitElement(node)
@@ -65,10 +67,10 @@ fun JsNode.resolveTemporaryNames() {
     })
 }
 
-private fun Map<JsScope, Set<JsScope>>.resolveNames(): Map<JsName, JsName> {
+private fun Map<JsScope, Set<JsScope>>.resolveNames(knownNames: Set<JsName>): Map<JsName, JsName> {
     val replacements = mutableMapOf<JsName, JsName>()
     fun traverse(scope: JsScope) {
-        for (temporaryName in scope.temporaryNames.sortedBy { it.ordinal }) {
+        for (temporaryName in scope.temporaryNames.filter { it in knownNames }.sortedBy { it.ordinal }) {
             replacements[temporaryName] = scope.declareFreshName(temporaryName.ident).apply { copyMetadataFrom(temporaryName) }
         }
         this[scope]!!.forEach(::traverse)

js/js.inliner/src/org/jetbrains/kotlin/js/inline/util/collectUtils.kt

@@ -25,8 +25,23 @@ import org.jetbrains.kotlin.js.translate.utils.JsAstUtils
 fun collectFunctionReferencesInside(scope: JsNode): List<JsName> =
         collectReferencedNames(scope).filter { it.staticRef is JsFunction }
 
+fun collectReferencedTemporaryNames(scope: JsNode): Set<JsName> {
+    val references = mutableSetOf<JsName>()
+
+    object : RecursiveJsVisitor() {
+        override fun visitElement(node: JsNode) {
+            if (node is HasName) {
+                node.name?.let { references += it }
+            }
+            super.visitElement(node)
+        }
+    }.accept(scope)
+
+    return references
+}
+
 private fun collectReferencedNames(scope: JsNode): Set<JsName> {
-    val references = IdentitySet<JsName>()
+    val references = mutableSetOf<JsName>()
 
     object : RecursiveJsVisitor() {
         override fun visitBreak(x: JsBreak) { }
@@ -53,7 +68,7 @@ private fun collectReferencedNames(scope: JsNode): Set<JsName> {
 }
 
 fun collectUsedNames(scope: JsNode): Set<JsName> {
-    val references = IdentitySet<JsName>()
+    val references = mutableSetOf<JsName>()
 
     object : RecursiveJsVisitor() {
         override fun visitBreak(x: JsBreak) { }