Properly handle AsyncGeneratorUnwrapYieldResumption (microsoft#56150)

Author: rbuckton

src/compiler/factory/emitHelpers.ts

@@ -854,17 +854,18 @@ export const asyncGeneratorHelper: UnscopedEmitHelper = {
     scoped: false,
     dependencies: [awaitHelper],
     text: `
-            var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
-                if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
-                var g = generator.apply(thisArg, _arguments || []), i, q = [];
-                return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-                function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
-                function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
-                function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
-                function fulfill(value) { resume("next", value); }
-                function reject(value) { resume("throw", value); }
-                function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
-            };`,
+        var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
+            if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
+            var g = generator.apply(thisArg, _arguments || []), i, q = [];
+            return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+            function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+            function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
+            function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
+            function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
+            function fulfill(value) { resume("next", value); }
+            function reject(value) { resume("throw", value); }
+            function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
+        };`,
 };
 
 /** @internal */

src/testRunner/unittests/evaluation/asyncGenerator.ts

@@ -62,4 +62,25 @@ describe("unittests:: evaluation:: asyncGeneratorEvaluation", () => {
             { done: true, value: undefined },
         ]);
     });
+    it("pass promise to gen.return()", async () => {
+        const result = evaluator.evaluateTypeScript(
+            `
+        export const output = [];
+        async function* fn() {
+            yield* [1]
+            return 3
+        }
+        export async function main() {
+            const it = fn();
+            output.push(await it.next());
+            output.push(await it.return(Promise.resolve(2)));
+        }`,
+            { target: ts.ScriptTarget.ES2017 },
+        );
+        await result.main();
+        assert.deepEqual(result.output, [
+            { done: false, value: 1 },
+            { done: true, value: 2 },
+        ]);
+    });
 });

tests/baselines/reference/asyncImportNestedYield.js

@@ -37,8 +37,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }

tests/baselines/reference/awaitUsingDeclarations.1(target=es2015).js

@@ -158,8 +158,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }

tests/baselines/reference/awaitUsingDeclarations.1(target=es2017).js

@@ -149,8 +149,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }

tests/baselines/reference/awaitUsingDeclarations.1(target=es5).js

@@ -185,8 +185,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }

tests/baselines/reference/blockScopedVariablesUseBeforeDef.js

@@ -198,8 +198,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }

tests/baselines/reference/dependentDestructuredVariables.js

@@ -451,8 +451,9 @@ var __await = (this && this.__await) || function (v) { return this instanceof __
 var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
     if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
     var g = generator.apply(thisArg, _arguments || []), i, q = [];
-    return i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i;
-    function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }
+    return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
+    function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
+    function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
     function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
     function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
     function fulfill(value) { resume("next", value); }