feat(groupBy): Accept number and symbol keys in groupBy

toss · Jun 30, 2024 · 517401f · 517401f
1 parent fc1a8e6
commit 517401f
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Showing 2 changed files with 22 additions and 2 deletions.
diff --git a/src/array/groupBy.spec.ts b/src/array/groupBy.spec.ts
@@ -51,7 +51,7 @@ describe('groupBy', () => {
       { score: 1, name: 'Joe' },
     ];
 
-    const result = groupBy(array, item => item.score.toString());
+    const result = groupBy(array, item => item.score);
 
     expect(result).toEqual({
       '1': [
@@ -62,6 +62,26 @@ describe('groupBy', () => {
     });
   });
 
+  it('should group elements by a symbol key', () => {
+    const TYPE_A = Symbol();
+    const TYPE_B = Symbol();
+    const array = [
+      { type: TYPE_A, score: 1, name: 'John' },
+      { type: TYPE_A, score: 2, name: 'Jane' },
+      { type: TYPE_B, score: 1, name: 'Joe' },
+    ];
+
+    const result = groupBy(array, item => item.type);
+
+    expect(result).toEqual({
+      [TYPE_A]: [
+        { type: TYPE_A, score: 1, name: 'John' },
+        { type: TYPE_A, score: 2, name: 'Jane' },
+      ],
+      [TYPE_B]: [{ type: TYPE_B, score: 1, name: 'Joe' }],
+    });
+  });
+
   it('should handle duplicate keys correctly', () => {
     const array = [
       { category: 'fruit', name: 'apple' },

diff --git a/src/array/groupBy.ts b/src/array/groupBy.ts
@@ -28,7 +28,7 @@
  * //   ]
  * // }
  */
-export function groupBy<T, K extends string>(arr: readonly T[], getKeyFromItem: (item: T) => K): Record<K, T[]> {
+export function groupBy<T, K extends PropertyKey>(arr: readonly T[], getKeyFromItem: (item: T) => K): Record<K, T[]> {
   const result = {} as Record<K, T[]>;
 
   for (const item of arr) {