types(middleware): make this in document middleware the hydrated doc type, not raw doc type

Fix #15242

Author: vkarpov15

test/types/middleware.test.ts

@@ -200,3 +200,60 @@ function gh13601() {
     expectAssignable<Document>(this);
   });
 }
+
+function gh15242() {
+  type PostPersisted = {
+    title: string,
+    postTime: Date
+  };
+
+  type ValidatorThis = DocumentValidatorThis | QueryValidatorThis;
+  type DocumentValidatorThis = HydratedDocument<PostPersisted>;
+  type QueryValidatorThis = Query<PostRecord, PostRecord>;
+
+  const PostSchema = new Schema<PostPersisted>({
+    title: { type: String, required: true },
+    postTime: {
+      type: Date,
+      required: true,
+      validate: {
+        validator: async function(this: ValidatorThis, postTime: Date): Promise<boolean> {
+          return true;
+        }
+      }
+    }
+  });
+
+  type PostRecord = HydratedDocument<PostPersisted>;
+  const PostModel = model<PostPersisted>('Post', PostSchema);
+}
+
+function gh15242WithVirtuals() {
+  type PostPersisted = {
+    title: string,
+    postTime: Date
+  };
+
+  type ValidatorThis = DocumentValidatorThis | QueryValidatorThis;
+  type DocumentValidatorThis = HydratedDocument<PostPersisted, { myVirtual: number }>;
+  type QueryValidatorThis = Query<PostRecord, PostRecord>;
+
+  const PostSchema = new Schema({
+    title: { type: String, required: true },
+    postTime: {
+      type: Date,
+      required: true,
+      validate: {
+        validator: async function(this: ValidatorThis, postTime: Date): Promise<boolean> {
+          if (!(this instanceof Query)) {
+            expectType<number>(this.myVirtual);
+          }
+          return true;
+        }
+      }
+    }
+  }, { virtuals: { myVirtual: { get() { return 42; } } } });
+
+  type PostRecord = HydratedDocument<PostPersisted, { myVirtual: number }>;
+  const PostModel = model<PostPersisted>('Post', PostSchema);
+}

types/index.d.ts

@@ -541,21 +541,21 @@ declare module 'mongoose' {
           ? DateSchemaDefinition
           : (Function | string);
 
-  export type SchemaDefinitionProperty<T = undefined, EnforcedDocType = any> = SchemaDefinitionWithBuiltInClass<T> |
-  SchemaTypeOptions<T extends undefined ? any : T, EnforcedDocType> |
-    typeof SchemaType |
-  Schema<any, any, any> |
-  Schema<any, any, any>[] |
-  SchemaTypeOptions<T extends undefined ? any : Unpacked<T>, EnforcedDocType>[] |
-  Function[] |
-  SchemaDefinition<T, EnforcedDocType> |
-  SchemaDefinition<Unpacked<T>, EnforcedDocType>[] |
-    typeof Schema.Types.Mixed |
-  MixedSchemaTypeOptions<EnforcedDocType>;
-
-  export type SchemaDefinition<T = undefined, EnforcedDocType = any> = T extends undefined
+  export type SchemaDefinitionProperty<T = undefined, EnforcedDocType = any, THydratedDocumentType = HydratedDocument<EnforcedDocType>> = SchemaDefinitionWithBuiltInClass<T>
+    | SchemaTypeOptions<T extends undefined ? any : T, EnforcedDocType, THydratedDocumentType>
+    | typeof SchemaType
+    | Schema<any, any, any>
+    | Schema<any, any, any>[]
+    | SchemaTypeOptions<T extends undefined ? any : Unpacked<T>, EnforcedDocType, THydratedDocumentType>[]
+    | Function[]
+    | SchemaDefinition<T, EnforcedDocType, THydratedDocumentType>
+    | SchemaDefinition<Unpacked<T>, EnforcedDocType, THydratedDocumentType>[]
+    | typeof Schema.Types.Mixed
+    | MixedSchemaTypeOptions<EnforcedDocType>;
+
+  export type SchemaDefinition<T = undefined, EnforcedDocType = any, THydratedDocumentType = HydratedDocument<EnforcedDocType>> = T extends undefined
     ? { [path: string]: SchemaDefinitionProperty; }
-    : { [path in keyof T]?: SchemaDefinitionProperty<T[path], EnforcedDocType>; };
+    : { [path in keyof T]?: SchemaDefinitionProperty<T[path], EnforcedDocType, THydratedDocumentType>; };
 
   export type AnyArray<T> = T[] | ReadonlyArray<T>;
   export type ExtractMongooseArray<T> = T extends Types.Array<any> ? AnyArray<Unpacked<T>> : T;

types/schematypes.d.ts

@@ -56,7 +56,7 @@ declare module 'mongoose' {
 
   type DefaultType<T> = T extends Schema.Types.Mixed ? any : Partial<ExtractMongooseArray<T>>;
 
-  class SchemaTypeOptions<T, EnforcedDocType = any> {
+  class SchemaTypeOptions<T, EnforcedDocType = any, THydratedDocumentType = HydratedDocument<EnforcedDocType>> {
     type?:
     T extends string ? StringSchemaDefinition :
       T extends number ? NumberSchemaDefinition :
@@ -65,19 +65,19 @@ declare module 'mongoose' {
             T extends Map<any, any> ? SchemaDefinition<typeof Map> :
               T extends Buffer ? SchemaDefinition<typeof Buffer> :
                 T extends Types.ObjectId ? ObjectIdSchemaDefinition :
-                  T extends Types.ObjectId[] ? AnyArray<ObjectIdSchemaDefinition> | AnyArray<SchemaTypeOptions<ObjectId, EnforcedDocType>> :
-                    T extends object[] ? (AnyArray<Schema<any, any, any>> | AnyArray<SchemaDefinition<Unpacked<T>>> | AnyArray<SchemaTypeOptions<Unpacked<T>, EnforcedDocType>>) :
-                      T extends string[] ? AnyArray<StringSchemaDefinition> | AnyArray<SchemaTypeOptions<string, EnforcedDocType>> :
-                        T extends number[] ? AnyArray<NumberSchemaDefinition> | AnyArray<SchemaTypeOptions<number, EnforcedDocType>> :
-                          T extends boolean[] ? AnyArray<BooleanSchemaDefinition> | AnyArray<SchemaTypeOptions<boolean, EnforcedDocType>> :
-                            T extends Function[] ? AnyArray<Function | string> | AnyArray<SchemaTypeOptions<Unpacked<T>, EnforcedDocType>> :
+                  T extends Types.ObjectId[] ? AnyArray<ObjectIdSchemaDefinition> | AnyArray<SchemaTypeOptions<ObjectId, EnforcedDocType, THydratedDocumentType>> :
+                    T extends object[] ? (AnyArray<Schema<any, any, any>> | AnyArray<SchemaDefinition<Unpacked<T>>> | AnyArray<SchemaTypeOptions<Unpacked<T>, EnforcedDocType, THydratedDocumentType>>) :
+                      T extends string[] ? AnyArray<StringSchemaDefinition> | AnyArray<SchemaTypeOptions<string, EnforcedDocType, THydratedDocumentType>> :
+                        T extends number[] ? AnyArray<NumberSchemaDefinition> | AnyArray<SchemaTypeOptions<number, EnforcedDocType, THydratedDocumentType>> :
+                          T extends boolean[] ? AnyArray<BooleanSchemaDefinition> | AnyArray<SchemaTypeOptions<boolean, EnforcedDocType, THydratedDocumentType>> :
+                            T extends Function[] ? AnyArray<Function | string> | AnyArray<SchemaTypeOptions<Unpacked<T>, EnforcedDocType, THydratedDocumentType>> :
                               T | typeof SchemaType | Schema<any, any, any> | SchemaDefinition<T> | Function | AnyArray<Function>;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string | string[];
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: SchemaValidator<T, EnforcedDocType> | AnyArray<SchemaValidator<T, EnforcedDocType>>;
+    validate?: SchemaValidator<T, EnforcedDocType, THydratedDocumentType> | AnyArray<SchemaValidator<T, EnforcedDocType, THydratedDocumentType>>;
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string |

types/validation.d.ts

@@ -1,6 +1,11 @@
 declare module 'mongoose' {
 
-  type SchemaValidator<T, EnforcedDocType> = RegExp | [RegExp, string] | Function | [Function, string] | ValidateOpts<T, EnforcedDocType> | ValidateOpts<T, EnforcedDocType>[];
+  type SchemaValidator<T, EnforcedDocType, THydratedDocumentType> = RegExp
+    | [RegExp, string]
+    | Function
+    | [Function, string]
+    | ValidateOpts<T, THydratedDocumentType>
+    | ValidateOpts<T, THydratedDocumentType>[];
 
   interface ValidatorProps {
     path: string;