feat: support for of loop label

Author: axetroy

README.md

@@ -71,6 +71,16 @@ try {
   * [ ] Try with optional catch
   * [ ] Decorator
 
+## Test
+
+I have write a lot of test case for this, look at [here](https://github.com/axetroy/vm.js/tree/master/test)
+
+Now it still in development, got a lot of work to do and more detail to resolve.
+
+I will release the first stable version after write 500 test case.
+
+If you want to join it. welcome to PR.
+
 ## Contributors
 
 <!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->

src/evaluate.ts

@@ -466,11 +466,19 @@ const visitors: EvaluateMap = {
   },
   // @es2015 for of
   ForOfStatement(path) {
-    const { node, scope } = path;
+    const { node, scope, ctx } = path;
+    const labelName: string | void = ctx.labelName;
     const entity = evaluate(path.createChild(node.right));
+    const SymbolConst: any =
+      typeof Symbol !== "undefined"
+        ? Symbol
+        : (() => {
+            const $var = scope.hasBinding("Symbol");
+            return $var ? $var.value : undefined;
+          })();
     // not support for of, it mean not support native for of
-    if (typeof Symbol !== "undefined") {
-      if (!entity || !entity[Symbol.iterator]) {
+    if (SymbolConst) {
+      if (!entity || !entity[SymbolConst.iterator]) {
         // FIXME: how to get function name
         // for (let value of get()){}
         throw ErrInvalidIterable((node.right as types.Identifier).name);
@@ -490,7 +498,26 @@ const visitors: EvaluateMap = {
         forOfScope.invasive = true;
         forOfScope.isolated = false;
         forOfScope.declare(node.left.kind, varName, value); // define in current scope
-        evaluate(path.createChild(node.body, forOfScope));
+        const signal = evaluate(path.createChild(node.body, forOfScope));
+        if (Signal.isBreak(signal)) {
+          if (!signal.value) {
+            break;
+          }
+          if (signal.value === labelName) {
+            break;
+          }
+          return signal;
+        } else if (Signal.isContinue(signal)) {
+          if (!signal.value) {
+            continue;
+          }
+          if (signal.value === labelName) {
+            continue;
+          }
+          return signal;
+        } else if (Signal.isReturn(signal)) {
+          return signal;
+        }
       }
     } else if (isIdentifier(node.left)) {
       /**
@@ -503,7 +530,26 @@ const visitors: EvaluateMap = {
         const forOfScope = scope.createChild("forOf");
         forOfScope.invasive = true;
         scope.var(varName, value); // define in parent scope
-        evaluate(path.createChild(node.body, forOfScope));
+        const signal = evaluate(path.createChild(node.body, forOfScope));
+        if (Signal.isBreak(signal)) {
+          if (!signal.value) {
+            break;
+          }
+          if (signal.value === labelName) {
+            break;
+          }
+          return signal;
+        } else if (Signal.isContinue(signal)) {
+          if (!signal.value) {
+            continue;
+          }
+          if (signal.value === labelName) {
+            continue;
+          }
+          return signal;
+        } else if (Signal.isReturn(signal)) {
+          return signal;
+        }
       }
     }
   },

test/es2015/for-of/label.test.ts

@@ -0,0 +1,43 @@
+import test from "ava";
+import { ErrDuplicateDeclard } from "../../../src/error";
+import vm from "../../../src/vm";
+
+test("break with label", t => {
+  const sandbox: any = vm.createContext({});
+
+  const index: any = vm.runInContext(
+    `
+loop1:
+for (var index of [0, 1, 2, 3]){
+  if (index===2){
+    break loop1;
+  }
+}
+
+module.exports = index;
+  `,
+    sandbox
+  );
+  t.deepEqual(index, 2);
+});
+
+test("continue with label", t => {
+  const sandbox: any = vm.createContext({});
+
+  const list: any = vm.runInContext(
+    `
+var list = [];
+loop1:
+for (var index of [0, 1, 2, 3]){
+  if (index%2 === 0){
+    continue;
+  }
+  list.push(index);
+}
+
+module.exports = list;
+  `,
+    sandbox
+  );
+  t.deepEqual(list, [1, 3]);
+});