rewrite GetRouteParameter to work on long paths #54151 (comment)

DetachHead · DetachHead · commit 0f83c2c2d6b0 · 2021-07-03T13:23:41.000+10:00
diff --git a/types/express-serve-static-core/express-serve-static-core-tests.ts b/types/express-serve-static-core/express-serve-static-core-tests.ts
@@ -80,12 +80,11 @@ app.get('/:foo/:bar(\\d:+)/:baz', req => {
     req.params.quxx; // $ExpectType string
 });
 
-// long path parameters - not supported - https://github.com/DefinitelyTyped/DefinitelyTyped/pull/53513#issuecomment-870550063
+// long path parameters - https://github.com/DefinitelyTyped/DefinitelyTyped/pull/53513#issuecomment-870550063
 app.get('/website-api/jobalarm/:jobalarmId/:subscriptionId/search', req => {
-    req.params.foo; // $ExpectType string
-    req.params.bar; // $ExpectType string
-    req.params.qux; // $ExpectType string
-    req.params.quxx; // $ExpectType string
+    req.params.jobalarmId; // $ExpectType string
+    req.params.subscriptionId; // $ExpectType string
+    req.params.foo; // $ExpectError
 });
 
 // Query can be a custom type
diff --git a/types/express-serve-static-core/index.d.ts b/types/express-serve-static-core/index.d.ts
@@ -98,13 +98,11 @@ export type RequestHandlerParams<
     | ErrorRequestHandler<P, ResBody, ReqBody, ReqQuery, Locals>
     | Array<RequestHandler<P> | ErrorRequestHandler<P>>;
 
-type GetRouteParameter<RouteAfterColon extends string, Depth extends never[] = []> = Depth['length'] extends 10
-    ? never
-    : RouteAfterColon extends `${infer Char}${infer Rest}`
-    ? Char extends '/' | '-' | '.'
-        ? ''
-        : `${Char}${GetRouteParameter<Rest, [...Depth, never]>}`
-    : RouteAfterColon;
+type RemoveTail<S extends string, Tail extends string> = S extends `${infer P}${Tail}` ? P : S;
+type GetRouteParameter<S extends string> = RemoveTail<
+    RemoveTail<RemoveTail<S, `/${string}`>, `-${string}`>,
+    `.${string}`
+>;
 
 // prettier-ignore
 export type RouteParameters<Route extends string> = string extends Route
