Improve inferred types for _raw property (#820)

This PR makes improvements regarding the `_raw` property of `Document`
instances (which also impacts `Model` since it extends `Document`).

The following changes are included:
- `DocumentData` will now include the `_raw` property if the schema is
null
- `DocumentCompositeValue` will now include the `_raw` property if the
schema is null
- `InferDocumentObject` now accepts a `null` schema in its generic. If
the schema is `null` then the `_raw` property will be included on the
inferred output
- `InferModelObject` now accepts a `null` schema in its generic. If the
schema is `null` then the `_raw` property will be included on the
inferred output

src/Document.ts

@@ -7,9 +7,9 @@ import type { DbServerDelimiters, DeepOptionalNullable, MvRecord } from './types
 
 // #region Types
 /** Type of data property for constructing a document dependent upon the schema */
-export type DocumentData<TSchema extends Schema | null> = TSchema extends Schema
-	? DeepOptionalNullable<InferDocumentObject<TSchema>>
-	: never;
+export type DocumentData<TSchema extends Schema | null> = DeepOptionalNullable<
+	InferDocumentObject<TSchema>
+>;
 
 export interface DocumentConstructorOptions<TSchema extends Schema | null> {
 	data?: DocumentData<TSchema>;
@@ -27,9 +27,8 @@ export interface BuildForeignKeyDefinitionsResult {
  * An intersection type that combines the `Document` class instance with the
  * inferred shape of the document object based on the schema definition.
  */
-export type DocumentCompositeValue<TSchema extends Schema | null> = TSchema extends Schema
-	? Document<TSchema> & InferDocumentObject<TSchema>
-	: Document<TSchema>;
+export type DocumentCompositeValue<TSchema extends Schema | null> = Document<TSchema> &
+	InferDocumentObject<TSchema>;
 // #endregion
 
 /** A document object */

src/Schema.ts

@@ -40,6 +40,7 @@ import type {
 	ISOCalendarDateTime,
 	ISOTime,
 	MarkRequired,
+	MvRecord,
 	Remap,
 } from './types';
 
@@ -152,17 +153,17 @@ type InferSchemaType<TSchemaTypeDefinition, TConstraint> =
  *
  * Allows a constraint to be specified to filter the output to only include properties of a specific type
  */
-export type InferDocumentObject<TSchema extends Schema, TConstraint = SchemaTypeDefinition> =
+export type InferDocumentObject<TSchema extends Schema | null, TConstraint = SchemaTypeDefinition> =
 	TSchema extends Schema<infer TSchemaDefinition>
 		? {
 				[K in keyof TSchemaDefinition as TSchemaDefinition[K] extends TConstraint
 					? K
 					: never]: InferSchemaType<TSchemaDefinition[K], TConstraint>;
 			}
-		: never;
+		: { _raw: MvRecord };
 
 /** Infer the shape of a `Model` instance based upon the Schema it was instantiated with */
-export type InferModelObject<TSchema extends Schema> = Remap<
+export type InferModelObject<TSchema extends Schema | null> = Remap<
 	InferDocumentObject<TSchema> & RequiredModelMeta
 >;
 

src/__tests__/Document.test.ts

@@ -1133,5 +1133,10 @@ describe('utility types', () => {
 			> = true;
 			expect(test1).toBe(true);
 		});
+
+		test('should have a _raw property if schema is null', () => {
+			const test1: Equals<DocumentData<null>, { _raw: MvRecord }> = true;
+			expect(test1).toBe(true);
+		});
 	});
 });

src/__tests__/Schema.test.ts

@@ -27,7 +27,7 @@ import {
 	NumberType,
 	StringType,
 } from '../schemaType';
-import type { Equals, ISOCalendarDate, ISOCalendarDateTime, ISOTime } from '../types';
+import type { Equals, ISOCalendarDate, ISOCalendarDateTime, ISOTime, MvRecord } from '../types';
 
 describe('constructor', () => {
 	describe('errors', () => {
@@ -828,6 +828,13 @@ describe('utility types', () => {
 				expect(test1).toBe(true);
 			});
 		});
+
+		describe('null schema', () => {
+			test('should have the _raw property', () => {
+				const test1: Equals<InferDocumentObject<null>, { _raw: MvRecord }> = true;
+				expect(test1).toBe(true);
+			});
+		});
 	});
 
 	describe('InferModelObject', () => {
@@ -931,11 +938,7 @@ describe('utility types', () => {
 				const schema1 = new Schema({ isoTimeProp: { type: 'ISOTime', path: '1' } });
 				const test1: Equals<
 					InferModelObject<typeof schema1>,
-					{
-						_id: string;
-						__v: string;
-						isoTimeProp: ISOTime | null;
-					}
+					{ _id: string; __v: string; isoTimeProp: ISOTime | null }
 				> = true;
 				expect(test1).toBe(true);
 
@@ -1250,6 +1253,16 @@ describe('utility types', () => {
 				expect(test1).toBe(true);
 			});
 		});
+
+		describe('null schema', () => {
+			test('should have the _raw property', () => {
+				const test1: Equals<
+					InferModelObject<null>,
+					{ _id: string; __v: string; _raw: MvRecord }
+				> = true;
+				expect(test1).toBe(true);
+			});
+		});
 	});
 
 	describe('FlattenDocument', () => {

src/compileModel.ts

@@ -29,18 +29,18 @@ export type ModelConstructor<TSchema extends Schema | null> = ReturnType<
 
 export type Model<TSchema extends Schema | null> = InstanceType<ModelConstructor<TSchema>>;
 
-/** Used as an intersection type to make _id & __v properties required */
-export interface RequiredModelMeta {
-	_id: string;
-	__v: string;
-}
+type RequiredModelMetaProperties = '_id' | '__v';
+/** Used as an intersection type to make specific model properties required */
+export type RequiredModelMeta = {
+	[K in RequiredModelMetaProperties]: NonNullable<Model<Schema>[K]>;
+};
 
 /**
  * An intersection type that combines the `Model` class instance with the
  * inferred shape of the model object based on the schema definition.
  */
 export type ModelCompositeValue<TSchema extends Schema | null> = Remap<
-	Model<TSchema> & (TSchema extends Schema ? InferModelObject<TSchema> : RequiredModelMeta)
+	Model<TSchema> & InferModelObject<TSchema>
 >;
 
 export interface ModelFindAndCountResult<TSchema extends Schema | null> {