recreate the tsc crash we're seeing in mongosh

Author: lerouxb

packages/mql-typescript/tests/real.ts

@@ -0,0 +1,156 @@
+/* eslint-disable @typescript-eslint/no-unused-vars */
+import type * as schema from '../out/schema';
+import type { Document } from 'bson';
+
+interface GenericCollectionSchema {
+  schema: Document;
+}
+interface GenericDatabaseSchema {
+  [key: string]: GenericCollectionSchema;
+}
+interface GenericServerSideSchema {
+  [key: string]: GenericDatabaseSchema;
+}
+type StringKey<T> = keyof T & string;
+
+class Mongo<M extends GenericServerSideSchema = GenericServerSideSchema> {}
+
+type CollectionWithSchema<
+  M extends GenericServerSideSchema = GenericServerSideSchema,
+  D extends GenericDatabaseSchema = M[keyof M],
+  C extends GenericCollectionSchema = D[keyof D],
+  N extends StringKey<D> = StringKey<D>,
+> = Collection<M, D, C, N> & {
+  [k in StringKey<D> as k extends `${N}.${infer S}` ? S : never]: Collection<
+    M,
+    D,
+    D[k],
+    k
+  >;
+};
+
+class Collection<
+  M extends GenericServerSideSchema = GenericServerSideSchema,
+  D extends GenericDatabaseSchema = M[keyof M],
+  C extends GenericCollectionSchema = D[keyof D],
+  N extends StringKey<D> = StringKey<D>,
+> {
+  _mongo: Mongo<M>;
+  _database: DatabaseWithSchema<M, D>;
+  _name: N;
+  constructor(
+    mongo: Mongo<M>,
+    database: DatabaseWithSchema<M, D> | Database<M, D>,
+    name: N,
+  ) {
+    this._mongo = mongo;
+    this._database = database as DatabaseWithSchema<M, D>;
+    this._name = name;
+  }
+  getName(): N {
+    return this._name;
+  }
+  async find(
+    query?: schema.Query<Document>,
+    projection?: Document,
+    options: Document = {},
+  ): Promise<schema.Query<Document> | undefined> {
+    //): Promise<Document | undefined> {
+    return Promise.resolve(query);
+  }
+}
+
+type DatabaseWithSchema<
+  M extends GenericServerSideSchema = GenericServerSideSchema,
+  D extends GenericDatabaseSchema = GenericDatabaseSchema,
+> = Database<M, D> & {
+  [k in StringKey<D>]: Collection<M, D, D[k], k>;
+};
+
+function isValidCollectionName(name: string): boolean {
+  return !!name && !/[$\0]/.test(name);
+}
+
+export class Database<
+  M extends GenericServerSideSchema = GenericServerSideSchema,
+  D extends GenericDatabaseSchema = GenericDatabaseSchema,
+> {
+  _mongo: Mongo<M>;
+  _name: StringKey<M>;
+  _collections: Record<StringKey<D>, CollectionWithSchema<M, D>>;
+
+  constructor(mongo: Mongo<M>, name: StringKey<M>) {
+    this._mongo = mongo;
+    this._name = name;
+    const collections: Record<
+      string,
+      CollectionWithSchema<M, D>
+    > = Object.create(null);
+    this._collections = collections;
+
+    const proxy = new Proxy(this, {
+      get: (target, prop): any => {
+        if (prop in target) {
+          return (target as any)[prop];
+        }
+
+        if (
+          typeof prop !== 'string' ||
+          prop.startsWith('_') ||
+          !isValidCollectionName(prop)
+        ) {
+          return;
+        }
+
+        if (!collections[prop]) {
+          collections[prop] = new Collection<M, D>(
+            mongo,
+            proxy,
+            prop,
+          ) as CollectionWithSchema<M, D>;
+        }
+
+        return collections[prop];
+      },
+    });
+    return proxy;
+  }
+
+  getCollection<K extends StringKey<D>>(
+    coll: K,
+  ): CollectionWithSchema<M, D, D[K], K> {
+    const collection = new Collection<M, D, D['myCollection']>(
+      this._mongo,
+      this,
+      'myCollection',
+    );
+
+    return collection as CollectionWithSchema<M, D, D[K], K>;
+  }
+}
+
+async function run() {
+  const serverSchema = {
+    myDatabase: {
+      myCollection: {
+        schema: {
+          _id: 'ObjectId',
+          name: 'string',
+          age: 'number',
+        },
+      },
+    },
+  };
+  const mongo = new Mongo<typeof serverSchema>();
+  const db = new Database<
+    typeof serverSchema,
+    (typeof serverSchema)['myDatabase']
+  >(mongo, 'myDatabase') as DatabaseWithSchema<
+    typeof serverSchema,
+    (typeof serverSchema)['myDatabase']
+  >;
+  const query = await db.myCollection.find({ name: 'foo' });
+  console.log(query);
+}
+
+run().catch(console.error);