1 files changed, 364 insertions, 0 deletions
diff --git a/std/node/_util/_util_callbackify_test.ts b/std/node/_util/_util_callbackify_test.ts
new file mode 100644
index 000000000..b4dcae755
--- /dev/null
+++ b/std/node/_util/_util_callbackify_test.ts
@@ -0,0 +1,364 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+//
+// Adapted from Node.js. Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+const { test } = Deno;
+import { assert, assertStrictEq } from "../../testing/asserts.ts";
+import { callbackify } from "./_util_callbackify.ts";
+
+const values = [
+  "hello world",
+  null,
+  undefined,
+  false,
+  0,
+  {},
+  { key: "value" },
+  Symbol("I am a symbol"),
+  function ok(): void {},
+  ["array", "with", 4, "values"],
+  new Error("boo"),
+];
+
+class TestQueue {
+  #waitingPromise: Promise<void>;
+  #resolve?: () => void;
+  #reject?: (err: unknown) => void;
+  #queueSize = 0;
+
+  constructor() {
+    this.#waitingPromise = new Promise((resolve, reject) => {
+      this.#resolve = resolve;
+      this.#reject = reject;
+    });
+  }
+
+  enqueue(fn: (done: () => void) => void): void {
+    this.#queueSize++;
+    try {
+      fn(() => {
+        this.#queueSize--;
+        if (this.#queueSize === 0) {
+          assert(
+            this.#resolve,
+            "Test setup error; async queue is missing #resolve"
+          );
+          this.#resolve();
+        }
+      });
+    } catch (err) {
+      assert(this.#reject, "Test setup error; async queue is missing #reject");
+      this.#reject(err);
+    }
+  }
+
+  waitForCompletion(): Promise<void> {
+    return this.#waitingPromise;
+  }
+}
+
+test("callbackify passes the resolution value as the second argument to the callback", async () => {
+  const testQueue = new TestQueue();
+
+  for (const value of values) {
+    // eslint-disable-next-line require-await
+    async function asyncFn(): Promise<typeof value> {
+      return value;
+    }
+    const cbAsyncFn = callbackify(asyncFn);
+    testQueue.enqueue((done) => {
+      cbAsyncFn((err: unknown, ret: unknown) => {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        done();
+      });
+    });
+
+    function promiseFn(): Promise<typeof value> {
+      return Promise.resolve(value);
+    }
+    const cbPromiseFn = callbackify(promiseFn);
+    testQueue.enqueue((done) => {
+      cbPromiseFn((err: unknown, ret: unknown) => {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        done();
+      });
+    });
+
+    function thenableFn(): PromiseLike<any> {
+      return {
+        then(onfulfilled): PromiseLike<any> {
+          assert(onfulfilled);
+          onfulfilled(value);
+          return this;
+        },
+      };
+    }
+    const cbThenableFn = callbackify(thenableFn);
+    testQueue.enqueue((done) => {
+      cbThenableFn((err: unknown, ret: unknown) => {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        done();
+      });
+    });
+  }
+
+  await testQueue.waitForCompletion();
+});
+
+test("callbackify passes the rejection value as the first argument to the callback", async () => {
+  const testQueue = new TestQueue();
+
+  for (const value of values) {
+    // eslint-disable-next-line require-await
+    async function asyncFn(): Promise<never> {
+      return Promise.reject(value);
+    }
+    const cbAsyncFn = callbackify(asyncFn);
+    assertStrictEq(cbAsyncFn.length, 1);
+    assertStrictEq(cbAsyncFn.name, "asyncFnCallbackified");
+    testQueue.enqueue((done) => {
+      cbAsyncFn((err: unknown, ret: unknown) => {
+        assertStrictEq(ret, undefined);
+        if (err instanceof Error) {
+          if ("reason" in err) {
+            assert(!value);
+            assertStrictEq((err as any).code, "ERR_FALSY_VALUE_REJECTION");
+            assertStrictEq((err as any).reason, value);
+          } else {
+            assertStrictEq(String(value).endsWith(err.message), true);
+          }
+        } else {
+          assertStrictEq(err, value);
+        }
+        done();
+      });
+    });
+
+    function promiseFn(): Promise<never> {
+      return Promise.reject(value);
+    }
+    const obj = {};
+    Object.defineProperty(promiseFn, "name", {
+      value: obj,
+      writable: false,
+      enumerable: false,
+      configurable: true,
+    });
+
+    const cbPromiseFn = callbackify(promiseFn);
+    assertStrictEq(promiseFn.name, obj);
+    testQueue.enqueue((done) => {
+      cbPromiseFn((err: unknown, ret: unknown) => {
+        assertStrictEq(ret, undefined);
+        if (err instanceof Error) {
+          if ("reason" in err) {
+            assert(!value);
+            assertStrictEq((err as any).code, "ERR_FALSY_VALUE_REJECTION");
+            assertStrictEq((err as any).reason, value);
+          } else {
+            assertStrictEq(String(value).endsWith(err.message), true);
+          }
+        } else {
+          assertStrictEq(err, value);
+        }
+        done();
+      });
+    });
+
+    function thenableFn(): PromiseLike<never> {
+      return {
+        then(onfulfilled, onrejected): PromiseLike<never> {
+          assert(onrejected);
+          onrejected(value);
+          return this;
+        },
+      };
+    }
+
+    const cbThenableFn = callbackify(thenableFn);
+    testQueue.enqueue((done) => {
+      cbThenableFn((err: unknown, ret: unknown) => {
+        assertStrictEq(ret, undefined);
+        if (err instanceof Error) {
+          if ("reason" in err) {
+            assert(!value);
+            assertStrictEq((err as any).code, "ERR_FALSY_VALUE_REJECTION");
+            assertStrictEq((err as any).reason, value);
+          } else {
+            assertStrictEq(String(value).endsWith(err.message), true);
+          }
+        } else {
+          assertStrictEq(err, value);
+        }
+        done();
+      });
+    });
+  }
+
+  await testQueue.waitForCompletion();
+});
+
+test("callbackify passes arguments to the original", async () => {
+  const testQueue = new TestQueue();
+
+  for (const value of values) {
+    // eslint-disable-next-line require-await
+    async function asyncFn<T>(arg: T): Promise<T> {
+      assertStrictEq(arg, value);
+      return arg;
+    }
+
+    const cbAsyncFn = callbackify(asyncFn);
+    assertStrictEq(cbAsyncFn.length, 2);
+    assert(Object.getPrototypeOf(cbAsyncFn) !== Object.getPrototypeOf(asyncFn));
+    assertStrictEq(Object.getPrototypeOf(cbAsyncFn), Function.prototype);
+    testQueue.enqueue((done) => {
+      cbAsyncFn(value, (err: unknown, ret: unknown) => {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        done();
+      });
+    });
+
+    function promiseFn<T>(arg: T): Promise<T> {
+      assertStrictEq(arg, value);
+      return Promise.resolve(arg);
+    }
+    const obj = {};
+    Object.defineProperty(promiseFn, "length", {
+      value: obj,
+      writable: false,
+      enumerable: false,
+      configurable: true,
+    });
+
+    const cbPromiseFn = callbackify(promiseFn);
+    assertStrictEq(promiseFn.length, obj);
+    testQueue.enqueue((done) => {
+      cbPromiseFn(value, (err: unknown, ret: unknown) => {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        done();
+      });
+    });
+  }
+
+  await testQueue.waitForCompletion();
+});
+
+test("callbackify preserves the `this` binding", async () => {
+  const testQueue = new TestQueue();
+
+  for (const value of values) {
+    const objectWithSyncFunction = {
+      fn(this: unknown, arg: typeof value): Promise<typeof value> {
+        assertStrictEq(this, objectWithSyncFunction);
+        return Promise.resolve(arg);
+      },
+    };
+    const cbSyncFunction = callbackify(objectWithSyncFunction.fn);
+    testQueue.enqueue((done) => {
+      cbSyncFunction.call(objectWithSyncFunction, value, function (
+        this: unknown,
+        err: unknown,
+        ret: unknown
+      ) {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        assertStrictEq(this, objectWithSyncFunction);
+        done();
+      });
+    });
+
+    const objectWithAsyncFunction = {
+      // eslint-disable-next-line require-await
+      async fn(this: unknown, arg: typeof value): Promise<typeof value> {
+        assertStrictEq(this, objectWithAsyncFunction);
+        return arg;
+      },
+    };
+    const cbAsyncFunction = callbackify(objectWithAsyncFunction.fn);
+    testQueue.enqueue((done) => {
+      cbAsyncFunction.call(objectWithAsyncFunction, value, function (
+        this: unknown,
+        err: unknown,
+        ret: unknown
+      ) {
+        assertStrictEq(err, null);
+        assertStrictEq(ret, value);
+        assertStrictEq(this, objectWithAsyncFunction);
+        done();
+      });
+    });
+  }
+
+  await testQueue.waitForCompletion();
+});
+
+test("callbackify throws with non-function inputs", () => {
+  ["foo", null, undefined, false, 0, {}, Symbol(), []].forEach((value) => {
+    try {
+      callbackify(value as any);
+      throw Error("We should never reach this error");
+    } catch (err) {
+      assert(err instanceof TypeError);
+      assertStrictEq((err as any).code, "ERR_INVALID_ARG_TYPE");
+      assertStrictEq(err.name, "TypeError");
+      assertStrictEq(
+        err.message,
+        'The "original" argument must be of type function.'
+      );
+    }
+  });
+});
+
+test("callbackify returns a function that throws if the last argument is not a function", () => {
+  // eslint-disable-next-line require-await
+  async function asyncFn(): Promise<number> {
+    return 42;
+  }
+
+  const cb = callbackify(asyncFn) as any;
+  const args: unknown[] = [];
+
+  ["foo", null, undefined, false, 0, {}, Symbol(), []].forEach((value) => {
+    args.push(value);
+
+    try {
+      cb(...args);
+      throw Error("We should never reach this error");
+    } catch (err) {
+      assert(err instanceof TypeError);
+      assertStrictEq((err as any).code, "ERR_INVALID_ARG_TYPE");
+      assertStrictEq(err.name, "TypeError");
+      assertStrictEq(
+        err.message,
+        "The last argument must be of type function."
+      );
+    }
+  });
+});