Improve syntax and tests for isomorphic events

mediamonks · Feb 17, 2019 · 06b96c2 · 06b96c2
1 parent b8b75ce
commit 06b96c2
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Showing 9 changed files with 175 additions and 305 deletions.
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "seng-event",
-  "version": "2.0.0-alpha.1",
+  "version": "2.0.0-alpha.2",
   "description": "Provides Classes and utilities for dispatching and listening to events.",
   "main": "./index.js",
   "types": "./index.d.ts",

diff --git a/src/index.ts b/src/index.ts
@@ -3,7 +3,6 @@ import { default as _export } from './lib/EventDispatcher';
 export { default as BaseEvent } from './lib/BaseEvent';
 export { default as createEventType } from './lib/createEventType';
 export { default as createIsomorphicEventType } from './lib/createIsomorphicEventType';
-export { default as IsomorphicBaseEvent } from './lib/IsomorphicBaseEvent';
 export { default as EventPhase } from './lib/EventPhase';
 export { default as EventListenerData } from './lib/EventListenerData';
 export { default as CallListenerResult } from './lib/CallListenerResult';

diff --git a/src/lib/EventDispatcher.ts b/src/lib/EventDispatcher.ts
@@ -6,8 +6,8 @@ import AbstractEvent from './AbstractEvent';
 import {
   EventHandlerForEvent,
   EventListenerMap,
-  ExtractEventsOfType,
   TypesForEvent,
+  ExtractEventOfType,
 } from './EventTypings';
 
 /**
@@ -146,7 +146,7 @@ export default class EventDispatcher<
    */
   public addEventListener<TType extends TypesForEvent<TEvent>>(
     eventType: TType,
-    handler: EventHandlerForEvent<ExtractEventsOfType<TEvent, TType>>,
+    handler: EventHandlerForEvent<ExtractEventOfType<TEvent, TType>>,
     useCapture: boolean = false,
     priority: number = 0,
   ) {
@@ -171,9 +171,9 @@ export default class EventDispatcher<
    * is set to false by default_
    * @returns {boolean} True if one or more event listeners exist
    */
-  public hasEventListener(
-    eventType: TypesForEvent<TEvent>,
-    handler?: EventHandlerForEvent<TEvent>,
+  public hasEventListener<TType extends TypesForEvent<TEvent>>(
+    eventType: TType,
+    handler?: EventHandlerForEvent<ExtractEventOfType<TEvent, TType>>,
     useCapture?: boolean,
   ): boolean {
     if (typeof handler === 'undefined') {
@@ -218,8 +218,8 @@ export default class EventDispatcher<
    * parameter will be removed. _Please note: if no useCapture argument is provided, only
    * event listeners that have useCapture set to false will be removed._
    */
-  public removeEventListener(
-    eventType: TypesForEvent<TEvent>,
+  public removeEventListener<TType extends TypesForEvent<TEvent>>(
+    eventType: TType,
     handler: EventHandlerForEvent<TEvent>,
     useCapture: boolean = false,
   ): void {

diff --git a/src/lib/EventTypings.ts b/src/lib/EventTypings.ts
@@ -6,50 +6,48 @@ export type TypesForEvent<TEvent extends AbstractEvent> = TEvent['type'];
 
 export type EventHandlerForEvent<TEvent extends AbstractEvent> = (event: TEvent) => any;
 
-export type EventListenerMap<TEvent extends AbstractEvent> = { [type: string]: Array<EventListenerData<TEvent>> };
-
-/**
- * Returns all TEvent['type'] that contain TType
- *
- * example
- * TEvent = { type: 'FOO'|'BAR' }|{ type: 'FOOBAR' }
- * TType = 'BAR'
- * ExtractEventType<TEvent, TType> = 'FOO'|'BAR'
- */
-type ExtractEventTypeIfContains<TEvent extends AbstractEvent, TType extends string> =
-  TType extends TEvent['type'] ? TEvent['type'] : never;
-
-/**
- * Returns all TEvent['type'] that contain TType
- *
- * example
- * TEvent = { type: 'FOO'|'BAR', ... }|{ type: 'FOOBAR', ... }
- * TType = 'BAR'
- * ExtractEventsContainsType<TEvent, TType> = { type: 'FOO'|'BAR', ... }
- */
-type ExtractEventIfTypeContains<TEvent extends AbstractEvent, TType extends string> =
-  TEvent extends { type: ExtractEventTypeIfContains<TEvent, TType> } ? TEvent : never;
-
-/**
- * If TEvent is an IsomorphicEvent (extends IsomorphicBaseEvent), narrow TEvent down to the
- * IsomorphicBaseEvent with TType.
- *
- * Example:
- * const FooEvent = createIsomorphicEventType<
- * 'CREATE',{ createId: number },'CHANGE',{ createId: number, newValue: string }
- * >({ CREATE: {}, CHANGE: { bubbles: true });
- * type FooEventType = InstanceType<typeof FooEvent>;
- *
- * const BarEvent = createEventType<{ barId: string }>()(['CREATE_BAR']);
- * type BarEventType = InstanceType<typeof BarEvent>;
- *
- * TEvent = FooEvent | BarEvent;
- * TType = 'CREATE';
- * UnpackIsomorphic<TEvent, TType> = FooEvent<'CREATE'> | BarEvent
- */
-type UnpackIsomorphic<TEvent extends AbstractEvent, TType extends string> =
-  TEvent extends IsomorphicBaseEvent<infer T, infer U, any> ? IsomorphicBaseEvent<T, U, TType> : TEvent;
-
-export type ExtractEventsOfType<TEvent extends AbstractEvent, TType extends string> =
-  UnpackIsomorphic<ExtractEventIfTypeContains<TEvent, TType>, TType>;
-
+export type EventListenerMap<TEvent extends AbstractEvent> = {
+  [type: string]: Array<EventListenerData<TEvent>>;
+};
+
+export type ExtractEventTypeIfContains<
+  TEvent extends AbstractEvent,
+  TType extends string
+> = TType extends TEvent['type'] ? TEvent['type'] : never;
+
+export type ExtractEventIfTypeContains<
+  TEvent extends AbstractEvent,
+  TType extends string
+> = TEvent extends { type: ExtractEventTypeIfContains<TEvent, TType> } ? TEvent : never;
+
+export type UnpackIsomorphic<
+  TEvent extends AbstractEvent,
+  TType extends string
+> = TEvent extends IsomorphicBaseEvent<infer T, infer U, any>
+  ? IsomorphicBaseEvent<T, U, TType>
+  : TEvent;
+
+export type ExtractEventOfType<
+  TEvent extends AbstractEvent,
+  TType extends string
+> = UnpackIsomorphic<ExtractEventIfTypeContains<TEvent, TType>, TType>;
+
+// prettier-ignore
+export type DataForIsomorphicEvent<
+  T extends string,
+  TTypes extends Array<string>,
+  TDataTypes extends Array<any>
+> =
+  T extends TTypes[0] ? TDataTypes[0]
+  : T extends TTypes[1] ? TDataTypes[1]
+  : T extends TTypes[2] ? TDataTypes[2]
+  : T extends TTypes[3] ? TDataTypes[3]
+  : T extends TTypes[4] ? TDataTypes[4]
+  : T extends TTypes[5] ? TDataTypes[5]
+  : T extends TTypes[6] ? TDataTypes[6]
+  : T extends TTypes[7] ? TDataTypes[7]
+  : T extends TTypes[8] ? TDataTypes[8]
+  : T extends TTypes[9] ? TDataTypes[9]
+  : T extends TTypes[10] ? TDataTypes[10]
+  : T extends TTypes[11] ? TDataTypes[11]
+  : never;
diff --git a/src/lib/IsomorphicBaseEvent.ts b/src/lib/IsomorphicBaseEvent.ts
@@ -1,51 +1,28 @@
 import BaseEvent from './BaseEvent';
+import { DataForIsomorphicEvent } from './EventTypings';
 
-export interface IEventOptions {
+export interface EventOptions {
   bubbles?: boolean;
   cancelable?: boolean;
   setTimeStamp?: boolean;
 }
 
-export type IEventOptionsMap<TTypes extends string> = {
-  [P in TTypes]: IEventOptions;
-};
-
-export type TypeMap<TType extends string> = { [P in TType]: P };
-
-interface IAnyTypeMap {
-  [type: string]: string;
-}
-
-export type TupleType<T> = [T, T, T, T, T, T];
-
-export type DataForIsomorphicEvent<
-  T extends string,
-  TTypes extends TupleType<string>,
-  TDataTypes extends TupleType<any>
-> =
-  T extends TTypes[0] ? TDataTypes[0] :
-  T extends TTypes[1] ? TDataTypes[1] :
-  T extends TTypes[2] ? TDataTypes[2] :
-  T extends TTypes[3] ? TDataTypes[3] :
-  T extends TTypes[4] ? TDataTypes[4] :
-  T extends TTypes[5] ? TDataTypes[5] : never;
+export type EventOptionsMap<TTypes extends string> = { [T in TTypes]: EventOptions };
 
 class IsomorphicBaseEvent<
-  TTypes extends TupleType<string>,
-  TDataTypes extends TupleType<any>,
-  TType extends TTypes[number],
+  TTypes extends Array<string>,
+  TDataTypes extends Array<any>,
+  TType extends TTypes[number]
 > extends BaseEvent<DataForIsomorphicEvent<TType, TTypes, TDataTypes>, TType> {
-  public static types:IAnyTypeMap;
-
-  public type:TType;
-  public data:DataForIsomorphicEvent<TType, TTypes, TDataTypes>;
+  public type: TType;
+  public data: DataForIsomorphicEvent<TType, TTypes, TDataTypes>;
 
-  private typeOptions:IEventOptionsMap<TTypes[number]>;
+  private typeOptions: EventOptionsMap<TTypes[number]>;
 
   constructor(
     type: TType,
     data: DataForIsomorphicEvent<TType, TTypes, TDataTypes>,
-    typeOptions:IEventOptionsMap<TTypes[number]>
+    typeOptions: EventOptionsMap<TTypes[number]>,
   ) {
     const { bubbles, cancelable, setTimeStamp } = typeOptions[type];
     super(type, data, bubbles, cancelable, setTimeStamp);

diff --git a/src/lib/createEventType.ts b/src/lib/createEventType.ts
@@ -8,178 +8,9 @@ interface IEventTypeClass<TData, TType extends string> {
 }
 
 function createEventType<TData>(bubbles?: boolean, cancelable?: boolean, setTimeStamp?: boolean) {
-  /*
-   * Overload signatures generated by running the following code:
-   * console.log(new Array(15).fill(0).map((_, i) => `function createEventTypeHelper<${new Array(i + 1).fill(0).map((_, index) => `T${index + 1} extends string`).join(', ')}>(\ntypes: [${new Array(i + 1).fill(0).map((_, index) => `T${index + 1}`).join(', ')}],\n): IEventTypeClass<TData, ${new Array(i + 1).fill(0).map((_, index) => `T${index + 1}`).join(' | ')}>;`).join('\n'));
-   */
-  function createEventTypeHelper<T1 extends string>(types: [T1]): IEventTypeClass<TData, T1>;
-  function createEventTypeHelper<T1 extends string, T2 extends string>(
-    types: [T1, T2],
-  ): IEventTypeClass<TData, T1 | T2>;
-  function createEventTypeHelper<T1 extends string, T2 extends string, T3 extends string>(
-    types: [T1, T2, T3],
-  ): IEventTypeClass<TData, T1 | T2 | T3>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string
-  >(types: [T1, T2, T3, T4]): IEventTypeClass<TData, T1 | T2 | T3 | T4>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string
-  >(types: [T1, T2, T3, T4, T5]): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string
-  >(types: [T1, T2, T3, T4, T5, T6]): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string
-  >(types: [T1, T2, T3, T4, T5, T6, T7]): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string,
-    T11 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10 | T11>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string,
-    T11 extends string,
-    T12 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10 | T11 | T12>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string,
-    T11 extends string,
-    T12 extends string,
-    T13 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13],
-  ): IEventTypeClass<TData, T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10 | T11 | T12 | T13>;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string,
-    T11 extends string,
-    T12 extends string,
-    T13 extends string,
-    T14 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14],
-  ): IEventTypeClass<
-    TData,
-    T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10 | T11 | T12 | T13 | T14
-  >;
-  function createEventTypeHelper<
-    T1 extends string,
-    T2 extends string,
-    T3 extends string,
-    T4 extends string,
-    T5 extends string,
-    T6 extends string,
-    T7 extends string,
-    T8 extends string,
-    T9 extends string,
-    T10 extends string,
-    T11 extends string,
-    T12 extends string,
-    T13 extends string,
-    T14 extends string,
-    T15 extends string
-  >(
-    types: [T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15],
-  ): IEventTypeClass<
-    TData,
-    T1 | T2 | T3 | T4 | T5 | T6 | T7 | T8 | T9 | T10 | T11 | T12 | T13 | T14 | T15
-  >;
-  function createEventTypeHelper(types: Array<string>) {
+  function createEventTypeHelper<TEventTypes extends Array<string>>(
+    ...types: TEventTypes
+  ): IEventTypeClass<TData, TEventTypes[number]> {
     class EventType extends BaseEvent<any, string> {
       public static types = types.reduce<TypeMap<string>>((result, t) => ({ ...result, t }), {});