[enhance] Improve normalizr type expressiveness

reactive · Oct 9, 2019 · 5058996 · 5058996
1 parent 139fb66
commit 5058996
Showing 1 changed file with 47 additions and 23 deletions.
diff --git a/src/resource/normal.d.ts b/src/resource/normal.d.ts
@@ -13,25 +13,29 @@ declare namespace schemas {
   ) => S;
   type EntityMap<T = any> = { [key: string]: Entity<T> };
 
-  export class Array<T = any> {
-    constructor(
-      definition: Schema<T>,
-      schemaAttribute?: string | SchemaFunction,
-    );
+  export class Array<S extends Schema = Schema<any>> {
+    private _identifier: 'Array';
+    constructor(definition: S, schemaAttribute?: string | SchemaFunction);
     define(definition: Schema): void;
+    readonly schema: S;
   }
 
-  export interface EntityOptions<T = any> {
-    idAttribute?: string | SchemaFunction;
+  export interface EntityOptions<T = any, ID = string> {
+    idAttribute?: string | SchemaFunction<ID>;
     mergeStrategy?: MergeFunction;
     processStrategy?: StrategyFunction<T>;
   }
 
-  export class Entity<T = any> {
-    constructor(key: string, definition?: Schema, options?: EntityOptions<T>);
+  export class Entity<T = any, K extends string = string> {
+    private _identifier: 'Entity';
+    constructor(
+      key: K,
+      definition?: Schema,
+      options?: EntityOptions<T, string>,
+    );
     define(definition: Schema): void;
-    key: string;
-    getId: SchemaFunction;
+    readonly key: K;
+    getId: SchemaFunction<string>;
     _processStrategy: StrategyFunction<T>;
   }
 
@@ -41,9 +45,11 @@ declare namespace schemas {
   > {
     constructor(definition: O);
     define(definition: Schema): void;
+    readonly schema: O;
   }
 
   export class Union<Choices extends EntityMap = any> {
+    private _identifier: 'Union';
     constructor(
       definition: Choices,
       schemaAttribute:
@@ -53,23 +59,26 @@ declare namespace schemas {
     define(definition: Schema): void;
     inferSchema: SchemaAttributeFunction<Choices[keyof Choices]>;
     getSchemaAttribute: SchemaFunction<keyof Choices>;
+    readonly schema: Choices;
   }
 
   export class Values<Choices extends EntityMap | Schema = any> {
+    private _identifier: 'Values';
     constructor(
       definition: Choices,
       schemaAttribute?: Choices extends EntityMap<infer T>
         ? keyof T | SchemaFunction<keyof Choices>
         : undefined,
     );
     define(definition: Schema): void;
-    isSingleSchema: Choices extends EntityMap ? false : true;
+    readonly isSingleSchema: Choices extends EntityMap ? false : true;
     inferSchema: SchemaAttributeFunction<
       Choices extends EntityMap ? Choices[keyof Choices] : Choices
     >;
     getSchemaAttribute: Choices extends EntityMap
       ? SchemaFunction<keyof Choices>
       : false;
+    readonly schema: Choices;
   }
 }
 
@@ -103,11 +112,14 @@ interface SchemaArray<T> extends Array<SchemaDetail<T>> {}
 export type SchemaDetail<T> =
   | schemas.Entity<T>
   | schemas.Object<T>
-  | schemas.Union<{ [key: string]: schemas.Entity<T> }>
-  | schemas.Values<{ [key: string]: schemas.Entity<T> } | schemas.Entity<T>>
+  | schemas.Union<schemas.EntityMap<T>>
+  | schemas.Values<schemas.Entity<T> | SchemaObjectOne<T>>
   | SchemaObjectOne<T>;
 
-export type SchemaList<T> = SchemaArray<T> | SchemaObjectMany<T>;
+export type SchemaList<T> =
+  | SchemaArray<T>
+  | SchemaObjectMany<T>
+  | schemas.Array<SchemaDetail<T>>;
 
 export type Schema<T = any> = SchemaDetail<T> | SchemaList<T>;
 
@@ -128,7 +140,7 @@ export function denormalize<S extends Schema>(
   entities: any,
 ): Denormalized<S>;
 
-export type Denormalized<S> = S extends schemas.Entity<infer T>
+export type DenormalizedCore<S> = S extends schemas.Entity<infer T>
   ? T
   : S extends schemas.Values<infer Choices>
   ? Record<
@@ -142,31 +154,43 @@ export type Denormalized<S> = S extends schemas.Entity<infer T>
   : S extends schemas.Union<infer Choices>
   ? (Choices[keyof Choices] extends schemas.Entity<infer T> ? T : never) // TODO: typescript 3.7 make this recursive instead
   : S extends schemas.Object<any, infer O>
-  ? { [K in keyof O]: O[K] extends Schema ? Denormalized<O[K]> : O[K] }
+  ? { [K in keyof O]: O[K] extends Schema ? DenormalizedCore<O[K]> : O[K] }
   : S extends { [key: string]: any }
-  ? { [K in keyof S]: S[K] extends Schema ? Denormalized<S[K]> : S[K] }
+  ? { [K in keyof S]: S[K] extends Schema ? DenormalizedCore<S[K]> : S[K] }
   : S;
 
 type UnionResult<Choices extends schemas.EntityMap> = {
   id: ReturnType<Choices[keyof Choices]['getId']>;
   schema: keyof Choices;
 };
 
-export type ResultType<S> = S extends schemas.Entity
-  ? ReturnType<S['getId']>
+export type Denormalized<S> = Extract<S, schemas.Entity<any>> extends never
+  ? (S extends (infer I)[] | schemas.Array<infer I>
+      ? DenormalizedCore<Extract<I, schemas.Entity<any>>>[]
+      : DenormalizedCore<S>)
+  : DenormalizedCore<Extract<S, schemas.Entity<any>>>;
+
+export type ResultTypeCore<S> = S extends schemas.Entity<any>
+  ? ReturnType<S['getId']> // should always be string
   : S extends schemas.Values<infer Choices>
   ? Record<
       string,
       Choices extends schemas.EntityMap
         ? UnionResult<Choices>
-        : Choices extends schemas.Entity
+        : Choices extends schemas.Entity<any>
         ? ReturnType<Choices['getId']> // TODO: typescript 3.7 let's us make this recursive
         : never
     >
   : S extends schemas.Union<infer Choices>
   ? UnionResult<Choices>
   : S extends schemas.Object<any, infer O>
-  ? { [K in keyof O]: O[K] extends Schema ? ResultType<O[K]> : O[K] }
+  ? { [K in keyof O]: O[K] extends Schema ? ResultTypeCore<O[K]> : O[K] }
   : S extends { [key: string]: any }
-  ? { [K in keyof S]: S[K] extends Schema ? ResultType<S[K]> : S[K] }
+  ? { [K in keyof S]: S[K] extends Schema ? ResultTypeCore<S[K]> : S[K] }
   : S;
+
+export type ResultType<S> = Extract<S, schemas.Entity<any>> extends never
+  ? (S extends (infer I)[] | schemas.Array<infer I>
+      ? ResultTypeCore<Extract<I, schemas.Entity<any>>>[]
+      : ResultTypeCore<S>)
+  : ResultTypeCore<Extract<S, schemas.Entity<any>>>;