Fix toLookup() type signature

emonkak · Nov 24, 2016 · f79139a · f79139a
1 parent 7cb94aa
commit f79139a
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Showing 3 changed files with 6 additions and 7 deletions.
diff --git a/src/extensions/toLookup.ts b/src/extensions/toLookup.ts
@@ -1,16 +1,16 @@
 import toLookupFn from '../toLookup';
 import { Enumerable } from '../internal/Enumerable';
 
-function toLookup<TSource, TKey>(this: Enumerable<TSource>, keySelector?: (element: TSource) => TKey): Map<TKey, TSource[]>;
-function toLookup<TSource, TKey, TElement>(this: Enumerable<TSource>, keySelector?: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]> {
+function toLookup<TSource, TKey>(this: Enumerable<TSource>, keySelector: (element: TSource) => TKey): Map<TKey, TSource[]>;
+function toLookup<TSource, TKey, TElement>(this: Enumerable<TSource>, keySelector: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]> {
     return toLookupFn.call(this.source, keySelector, elementSelector);
 }
 
 Enumerable.prototype.toLookup = toLookup;
 
 declare module '../internal/Enumerable' {
     interface Enumerable<TSource> {
-        toLookup<TKey>(keySelector?: (element: TSource) => TKey): Map<TKey, TSource[]>;
-        toLookup<TKey, TElement>(keySelector?: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]>;
+        toLookup<TKey>(keySelector: (element: TSource) => TKey): Map<TKey, TSource[]>;
+        toLookup<TKey, TElement>(keySelector: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]>;
     }
 }
diff --git a/src/toLookup.ts b/src/toLookup.ts
@@ -1,5 +1,5 @@
-export default function toLookup<TSource, TKey>(this: Iterable<TSource>, keySelector?: (element: TSource) => TKey): Map<TKey, TSource[]>;
-export default function toLookup<TSource, TKey, TElement>(this: Iterable<TSource>, keySelector?: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]> {
+export default function toLookup<TSource, TKey>(this: Iterable<TSource>, keySelector: (element: TSource) => TKey): Map<TKey, TSource[]>;
+export default function toLookup<TSource, TKey, TElement>(this: Iterable<TSource>, keySelector: (element: TSource) => TKey, elementSelector?: (element: TSource) => TElement): Map<TKey, TElement[]> {
     if (elementSelector == null) elementSelector = x => x as any;
 
     const lookup = new Map<TKey, TElement[]>();

diff --git a/test/toLookupTest.ts b/test/toLookupTest.ts
@@ -3,7 +3,6 @@ import Enumerable from '../src/';
 
 describe('toLookup()', () => {
     it('should creates a generic Map<TKey, TElement> from an Iterable<T>', () => {
-        assert.deepEqual(Array.from(new Enumerable([]).toLookup()), []);
         assert.deepEqual(Array.from(new Enumerable(['a', 'bc', 'def', 'gh', 'i']).toLookup(x => x.length)), [[1, ['a', 'i']], [2, ['bc', 'gh']], [3, ['def']]]);
         assert.deepEqual(Array.from(new Enumerable(['a', 'bc', 'def', 'gh', 'i']).toLookup(x => x.length, x => x + x)), [[1, ['aa', 'ii']], [2, ['bcbc', 'ghgh']], [3, ['defdef']]]);
     });