fix(NODE-3852,NODE-3854,NODE-3856): Misc typescript fixes for 4.3.1

src/collection.ts

@@ -102,7 +102,7 @@ import { WriteConcern, WriteConcernOptions } from './write_concern';
 
 /** @public */
 export interface ModifyResult<TSchema = Document> {
-  value: TSchema | null;
+  value: WithId<TSchema> | null;
   lastErrorObject?: Document;
   ok: 0 | 1;
 }

src/mongo_types.ts

@@ -65,11 +65,13 @@ export type EnhancedOmit<TRecordOrUnion, KeyUnion> = string extends keyof TRecor
 export type WithoutId<TSchema> = Omit<TSchema, '_id'>;
 
 /** A MongoDB filter can be some portion of the schema or a set of operators @public */
-export type Filter<TSchema> = {
-  [Property in Join<NestedPaths<WithId<TSchema>>, '.'>]?: Condition<
-    PropertyType<WithId<TSchema>, Property>
-  >;
-} & RootFilterOperators<WithId<TSchema>>;
+export type Filter<TSchema> =
+  | Partial<TSchema>
+  | ({
+      [Property in Join<NestedPaths<WithId<TSchema>>, '.'>]?: Condition<
+        PropertyType<WithId<TSchema>, Property>
+      >;
+    } & RootFilterOperators<WithId<TSchema>>);
 
 /** @public */
 export type Condition<T> = AlternativeType<T> | FilterOperators<AlternativeType<T>>;
@@ -477,8 +479,11 @@ export type PropertyType<Type, Property extends string> = string extends Propert
     : unknown
   : unknown;
 
-// We dont't support nested circular references
-/** @public */
+/**
+ * @public
+ * returns tuple of strings (keys to be joined on '.') that represent every path into a schema
+ * https://docs.mongodb.com/manual/tutorial/query-embedded-documents/
+ */
 export type NestedPaths<Type> = Type extends
   | string
   | number
@@ -497,6 +502,21 @@ export type NestedPaths<Type> = Type extends
   : // eslint-disable-next-line @typescript-eslint/ban-types
   Type extends object
   ? {
-      [Key in Extract<keyof Type, string>]: [Key, ...NestedPaths<Type[Key]>];
+      [Key in Extract<keyof Type, string>]: Type[Key] extends Type // type of value extends the parent
+        ? [Key]
+        : // for a recursive union type, the child will never extend the parent type.
+        // but the parent will still extend the child
+        Type extends Type[Key]
+        ? [Key]
+        : Type[Key] extends ReadonlyArray<infer ArrayType> // handling recursive types with arrays
+        ? Type extends ArrayType // is the type of the parent the same as the type of the array?
+          ? [Key] // yes, it's a recursive array type
+          : // for unions, the child type extends the parent
+          ArrayType extends Type
+          ? [Key] // we have a recursive array union
+          : // child is an array, but it's not a recursive array
+            [Key, ...NestedPaths<Type[Key]>]
+        : // child is not structured the same as the parent
+          [Key, ...NestedPaths<Type[Key]>];
     }[Extract<keyof Type, string>]
   : [];

test/types/community/collection/findX-recursive-types.test-d.ts

@@ -0,0 +1,175 @@
+import { expectError } from 'tsd';
+
+import type { Collection } from '../../../../src';
+
+/**
+ * mutually recursive types are not supported and will not get type safety
+ */
+interface A {
+  b: B;
+}
+
+interface B {
+  a: A;
+}
+
+declare const mutuallyRecursive: Collection<A>;
+//@ts-expect-error
+mutuallyRecursive.find({});
+mutuallyRecursive.find({
+  b: {}
+});
+
+/**
+ * types that are not recursive in name but are recursive in structure are
+ *   still supported
+ */
+interface RecursiveButNotReally {
+  a: { a: number; b: string };
+  b: string;
+}
+
+declare const recursiveButNotReallyCollection: Collection<RecursiveButNotReally>;
+expectError(
+  recursiveButNotReallyCollection.find({
+    'a.a': 'asdf'
+  })
+);
+recursiveButNotReallyCollection.find({
+  'a.a': 2
+});
+
+/**
+ * recursive schemas are now supported, but with limited type checking support
+ */
+interface RecursiveSchema {
+  name: RecursiveSchema;
+  age: number;
+}
+
+declare const recursiveCollection: Collection<RecursiveSchema>;
+recursiveCollection.find({
+  name: {
+    name: {
+      age: 23
+    }
+  }
+});
+
+recursiveCollection.find({
+  age: 23
+});
+
+/**
+ * Recursive optional schemas are also supported with the same capabilities as
+ *   standard recursive schemas
+ */
+interface RecursiveOptionalSchema {
+  name?: RecursiveOptionalSchema;
+  age: number;
+}
+
+declare const recursiveOptionalCollection: Collection<RecursiveOptionalSchema>;
+
+recursiveOptionalCollection.find({
+  name: {
+    name: {
+      age: 23
+    }
+  }
+});
+
+recursiveOptionalCollection.find({
+  age: 23
+});
+
+/**
+ * recursive union types are supported
+ */
+interface Node {
+  next: Node | null;
+}
+
+declare const nodeCollection: Collection<Node>;
+
+nodeCollection.find({
+  next: null
+});
+
+expectError(
+  nodeCollection.find({
+    next: 'asdf'
+  })
+);
+
+nodeCollection.find({
+  'next.next': 'asdf'
+});
+
+nodeCollection.find({ 'next.next.next': 'yoohoo' });
+
+/**
+ * Recursive schemas with arrays are also supported
+ */
+interface MongoStrings {
+  projectId: number;
+  branches: Branch[];
+  twoLevelsDeep: {
+    name: string;
+  };
+}
+
+interface Branch {
+  id: number;
+  name: string;
+  title?: string;
+  directories: Directory[];
+}
+
+interface Directory {
+  id: number;
+  name: string;
+  title?: string;
+  branchId: number;
+  files: (number | Directory)[];
+}
+
+declare const recursiveSchemaWithArray: Collection<MongoStrings>;
+expectError(
+  recursiveSchemaWithArray.findOne({
+    'branches.0.id': 'hello'
+  })
+);
+
+expectError(
+  recursiveSchemaWithArray.findOne({
+    'branches.0.directories.0.id': 'hello'
+  })
+);
+
+// type safety breaks after the first
+//   level of nested types
+recursiveSchemaWithArray.findOne({
+  'branches.0.directories.0.files.0.id': 'hello'
+});
+
+recursiveSchemaWithArray.findOne({
+  branches: [
+    {
+      id: 'asdf'
+    }
+  ]
+});
+
+// type inference works on properties but only at the top level
+expectError(
+  recursiveSchemaWithArray.findOne({
+    projectId: 'asdf'
+  })
+);
+
+recursiveSchemaWithArray.findOne({
+  twoLevelsDeep: {
+    name: 3
+  }
+});

test/types/community/collection/findX.test-d.ts

@@ -1,6 +1,6 @@
 import { expectAssignable, expectNotType, expectType } from 'tsd';
 
-import type { Projection, ProjectionOperators } from '../../../../src';
+import type { Filter, Projection, ProjectionOperators } from '../../../../src';
 import {
   Collection,
   Db,
@@ -300,3 +300,51 @@ expectAssignable<SchemaWithUserDefinedId | null>(await schemaWithUserDefinedId.f
 // should allow _id as a number
 await schemaWithUserDefinedId.findOne({ _id: 5 });
 await schemaWithUserDefinedId.find({ _id: 5 });
+
+// We should be able to use a doc of type T as a filter object when performing findX operations
+interface Foo {
+  a: string;
+}
+
+const fooObj: Foo = {
+  a: 'john doe'
+};
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const fooFilter: Filter<Foo> = fooObj;
+
+// Specifically test that arrays can be included as a part of an object
+//  ensuring that a bug reported in https://jira.mongodb.org/browse/NODE-3856 is addressed
+interface FooWithArray {
+  a: number[];
+}
+
+const fooObjWithArray: FooWithArray = {
+  a: [1, 2, 3, 4]
+};
+
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const fooFilterWithArray: Filter<FooWithArray> = fooObjWithArray;
+
+declare const coll: Collection<{ a: number; b: string }>;
+expectType<WithId<{ a: number; b: string }> | null>((await coll.findOneAndDelete({ a: 3 })).value);
+expectType<WithId<{ a: number; b: string }> | null>(
+  (await coll.findOneAndReplace({ a: 3 }, { a: 5, b: 'new string' })).value
+);
+expectType<WithId<{ a: number; b: string }> | null>(
+  (
+    await coll.findOneAndUpdate(
+      { a: 3 },
+      {
+        $set: {
+          a: 5
+        }
+      }
+    )
+  ).value
+);
+
+// projections do not change the return type - our typing doesn't support this
+expectType<WithId<{ a: number; b: string }> | null>(
+  (await coll.findOneAndDelete({ a: 3 }, { projection: { _id: 0 } })).value
+);