Fix JS DCE removing reachable functions

compiler/cli/src/org/jetbrains/kotlin/cli/js/dce/K2JSDce.kt

@@ -60,7 +60,7 @@ class K2JSDce : CLITool<K2JSDceArguments>() {
         }
         val dceResult = DeadCodeElimination.run(files, includedDeclarations, logConsumer)
         if (dceResult.status == DeadCodeEliminationStatus.FAILED) return ExitCode.COMPILATION_ERROR
-        val nodes = dceResult.reachableNodes
+        val nodes = dceResult.reachableNodes.filterTo(mutableSetOf()) { it.reachable }
 
         val reachabilitySeverity = if (arguments.printReachabilityInfo) CompilerMessageSeverity.INFO else CompilerMessageSeverity.LOGGING
         messageCollector.report(reachabilitySeverity, "")

js/js.dce/src/org/jetbrains/kotlin/js/dce/ReachabilityTracker.kt

@@ -57,9 +57,21 @@ class ReachabilityTracker(
             analysisResult.nodeMap[x] == null && x !in analysisResult.astNodesToEliminate
 
     override fun visitNameRef(nameRef: JsNameRef) {
-        if (nameRef in analysisResult.astNodesToSkip) return
+        if (visitNameLikeNode(nameRef)) {
+            super.visitNameRef(nameRef)
+        }
+    }
 
-        val node = context.extractNode(nameRef)
+    override fun visitArrayAccess(x: JsArrayAccess) {
+        if (visitNameLikeNode(x)) {
+            super.visitArrayAccess(x)
+        }
+    }
+
+    private fun visitNameLikeNode(x: JsExpression): Boolean {
+        if (x in analysisResult.astNodesToSkip) return false
+
+        val node = context.extractNode(x)
         if (node != null) {
             if (!node.reachable) {
                 reportAndNest("reach: referenced name $node", currentNodeWithLocation) {
@@ -67,9 +79,10 @@ class ReachabilityTracker(
                     currentNodeWithLocation?.let { node.usedByAstNodes += it }
                 }
             }
+            return false
         }
         else {
-            super.visitNameRef(nameRef)
+            return true
         }
     }
 
@@ -179,6 +192,7 @@ class ReachabilityTracker(
         }
         else if (!node.declarationReachable) {
             node.declarationReachable = true
+            reachableNodesImpl += node
 
             node.original.qualifier?.parent?.let {
                 reportAndNest("reach-decl: parent $it", null) {
@@ -197,8 +211,8 @@ class ReachabilityTracker(
     override fun visitPrefixOperation(x: JsPrefixOperation) {
         if (x.operator == JsUnaryOperator.TYPEOF) {
             val arg = x.arg
-            if (arg is JsNameRef && arg.qualifier == null) {
-                context.extractNode(arg)?.let { reachDeclaration(it) }
+            context.extractNode(arg)?.let {
+                reachDeclaration(it)
                 return
             }
         }

js/js.parser/src/com/google/gwt/dev/js/JsAstMapper.java

@@ -562,15 +562,18 @@ public class JsAstMapper {
         Node fromFnNameNode = fnNode.getFirstChild();
         Node fromParamNode = fnNode.getFirstChild().getNext().getFirstChild();
         Node fromBodyNode = fnNode.getFirstChild().getNext().getNext();
-        JsFunction toFn = scopeContext.enterFunction();
 
         // Decide the function's name, if any.
         //
         String fnNameIdent = fromFnNameNode.getString();
+        JsName functionName = null;
         if (fnNameIdent != null && fnNameIdent.length() > 0) {
-            toFn.setName(scopeContext.globalNameFor(fnNameIdent));
+            functionName = scopeContext.localNameFor(fnNameIdent);
         }
 
+        JsFunction toFn = scopeContext.enterFunction();
+        toFn.setName(functionName);
+
         while (fromParamNode != null) {
             String fromParamName = fromParamNode.getString();
             JsName name = scopeContext.localNameFor(fromParamName);

js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt

@@ -542,13 +542,14 @@ abstract class BasicBoxTest(
         val testFunctionFqn = testModuleName + (if (testPackage.isNullOrEmpty()) "" else ".$testPackage") + ".$testFunction"
         val additionalReachableNodes = setOf(
                 testFunctionFqn, "kotlin.kotlin.io.BufferedOutput", "kotlin.kotlin.io.output.flush",
-                "kotlin.kotlin.io.output.buffer", "kotlin-test.kotlin.test.overrideAsserter_wbnzx$"
+                "kotlin.kotlin.io.output.buffer", "kotlin-test.kotlin.test.overrideAsserter_wbnzx$",
+                "kotlin-test.kotlin.test.DefaultAsserter"
         )
         val allFilesToMinify = filesToMinify.values + kotlinJsInputFile + kotlinTestJsInputFile
         val dceResult = DeadCodeElimination.run(allFilesToMinify, additionalReachableNodes) { _, _ -> }
 
         val reachableNodes = dceResult.reachableNodes
-        minificationThresholdChecker(reachableNodes.size)
+        minificationThresholdChecker(reachableNodes.count { it.reachable })
 
         val runList = mutableListOf<String>()
         runList += kotlinJsLibOutput

js/js.tests/test/org/jetbrains/kotlin/js/test/DceTestGenerated.java

@@ -42,6 +42,12 @@ public class DceTestGenerated extends AbstractDceTest {
         doTest(fileName);
     }
 
+    @TestMetadata("arrayAccess.js")
+    public void testArrayAccess() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/dce/arrayAccess.js");
+        doTest(fileName);
+    }
+
     @TestMetadata("commonjs.js")
     public void testCommonjs() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/dce/commonjs.js");
@@ -53,4 +59,16 @@ public class DceTestGenerated extends AbstractDceTest {
         String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/dce/cycle.js");
         doTest(fileName);
     }
+
+    @TestMetadata("localVarAndFunction.js")
+    public void testLocalVarAndFunction() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/dce/localVarAndFunction.js");
+        doTest(fileName);
+    }
+
+    @TestMetadata("typeOf.js")
+    public void testTypeOf() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/dce/typeOf.js");
+        doTest(fileName);
+    }
 }

js/js.translator/testData/box/extensionFunction/extensionFunctionCalledFromFor.kt

@@ -1,4 +1,4 @@
-// EXPECTED_REACHABLE_NODES: 1230
+// EXPECTED_REACHABLE_NODES: 1106
 package foo
 
 class SimpleEnumerator {

js/js.translator/testData/box/multideclaration/multiValForMap.kt

@@ -1,4 +1,4 @@
-// EXPECTED_REACHABLE_NODES: 1222
+// EXPECTED_REACHABLE_NODES: 1098
 package foo
 
 

js/js.translator/testData/box/multideclaration/multiValForRange.kt

@@ -1,4 +1,4 @@
-// EXPECTED_REACHABLE_NODES: 1249
+// EXPECTED_REACHABLE_NODES: 1123
 package foo
 
 class C(val i: Int) : Comparable<C>, A() {

js/js.translator/testData/dce/arrayAccess.js

@@ -0,0 +1,17 @@
+(function(_) {
+    var x = {};
+    function foo() {
+        return x["bar"]();
+    }
+    x.bar = function() {
+        return "bar";
+    };
+    x.baz = function() {
+        return "baz";
+    };
+    _.foo = foo;
+})(module.exports);
+
+// REQUEST_REACHABLE: main.foo
+// ASSERT_REACHABLE: x.bar
+// ASSERT_UNREACHABLE: x.baz

js/js.translator/testData/dce/localVarAndFunction.js

@@ -0,0 +1,27 @@
+(function(_, Kotlin) {
+    Kotlin.defineInlineFunction("bar", Kotlin.wrapFunction(function() {
+        function baz() {
+            return "bar";
+        }
+        return function() {
+            return baz();
+        };
+    }));
+    return _;
+})(module.exports, require("kotlin"));
+
+(function(_) {
+    function baz() {
+        return "baz";
+    }
+
+    function foo() {
+       return baz();
+    }
+    _.foo = foo;
+})(module.exports);
+
+
+// REQUEST_REACHABLE: main.foo
+// ASSERT_REACHABLE: main.foo
+// ASSERT_REACHABLE: baz

js/js.translator/testData/dce/typeOf.js

@@ -0,0 +1,15 @@
+(function(_) {
+    var x = {};
+    x.y = {};
+    x.y.bar = function() {
+        return "bar";
+    };
+    function foo() {
+        return typeof x.y;
+    }
+    _.foo = foo;
+})(module.exports);
+
+// REQUEST_REACHABLE: main.foo
+// ASSERT_REACHABLE: x.y
+// ASSERT_UNREACHABLE: x.y.bar