improve(std/asserts): allow assert functions to specify type parameter (#6413)

3 files changed, 24 insertions, 7 deletions

diff --git a/std/node/_util/_util_callbackify_test.ts b/std/node/_util/_util_callbackify_test.ts
index d6a5d8664..e8a313905 100644
--- a/std/node/_util/_util_callbackify_test.ts
+++ b/std/node/_util/_util_callbackify_test.ts
@@ -246,7 +246,7 @@ Deno.test("callbackify passes arguments to the original", async () => {
 
   for (const value of values) {
     // eslint-disable-next-line require-await
-    async function asyncFn<T>(arg: T): Promise<T> {
+    async function asyncFn(arg: typeof value): Promise<typeof value> {
       assertStrictEquals(arg, value);
       return arg;
     }
@@ -263,7 +263,7 @@ Deno.test("callbackify passes arguments to the original", async () => {
       });
     });
 
-    function promiseFn<T>(arg: T): Promise<T> {
+    function promiseFn<T>(arg: typeof value): Promise<typeof value> {
       assertStrictEquals(arg, value);
       return Promise.resolve(arg);
     }
diff --git a/std/node/_util/_util_promisify.ts b/std/node/_util/_util_promisify.ts
index e3cc36a0c..ea2fb6a5e 100644
--- a/std/node/_util/_util_promisify.ts
+++ b/std/node/_util/_util_promisify.ts
@@ -21,13 +21,30 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+// Hack: work around the following TypeScript error:
+//   error: TS2345 [ERROR]: Argument of type 'typeof kCustomPromisifiedSymbol'
+//   is not assignable to parameter of type 'typeof kCustomPromisifiedSymbol'.
+//        assertStrictEquals(kCustomPromisifiedSymbol, promisify.custom);
+//                                                     ~~~~~~~~~~~~~~~~
+declare const _CustomPromisifiedSymbol: unique symbol;
+declare const _CustomPromisifyArgsSymbol: unique symbol;
+declare let Symbol: SymbolConstructor;
+interface SymbolConstructor {
+  for(key: "nodejs.util.promisify.custom"): typeof _CustomPromisifiedSymbol;
+  for(
+    key: "nodejs.util.promisify.customArgs"
+  ): typeof _CustomPromisifyArgsSymbol;
+}
+// End hack.
+
 // In addition to being accessible through util.promisify.custom,
-// this symbol is registered globally and can be accessed in any environment as Symbol.for('nodejs.util.promisify.custom')
+// this symbol is registered globally and can be accessed in any environment as
+// Symbol.for('nodejs.util.promisify.custom').
 const kCustomPromisifiedSymbol = Symbol.for("nodejs.util.promisify.custom");
-// This is an internal Node symbol used by functions returning multiple arguments
-// e.g. ['bytesRead', 'buffer'] for fs.read.
+// This is an internal Node symbol used by functions returning multiple
+// arguments, e.g. ['bytesRead', 'buffer'] for fs.read().
 const kCustomPromisifyArgsSymbol = Symbol.for(
-  "deno.nodejs.util.promisify.customArgs"
+  "nodejs.util.promisify.customArgs"
 );
 
 class NodeInvalidArgTypeError extends TypeError {
diff --git a/std/node/_util/_util_promisify_test.ts b/std/node/_util/_util_promisify_test.ts
index c6dbbd45a..4369a0132 100644
--- a/std/node/_util/_util_promisify_test.ts
+++ b/std/node/_util/_util_promisify_test.ts
@@ -30,7 +30,7 @@ import { promisify } from "./_util_promisify.ts";
 import * as fs from "../fs.ts";
 
 const readFile = promisify(fs.readFile);
-const customPromisifyArgs = Symbol.for("deno.nodejs.util.promisify.customArgs");
+const customPromisifyArgs = Symbol.for("nodejs.util.promisify.customArgs");
 
 Deno.test(
   "Errors should reject the promise",