wip: migrate to bun

test/groupBy.spec.ts

@@ -0,0 +1,90 @@
+import assert from 'node:assert';
+import lodashStable from 'lodash';
+import { LARGE_ARRAY_SIZE } from './utils';
+import groupBy from '../src/groupBy';
+
+describe('groupBy', () => {
+    const array = [6.1, 4.2, 6.3];
+
+    it('should transform keys by `iteratee`', () => {
+        const actual = groupBy(array, Math.floor);
+        assert.deepStrictEqual(actual, { '4': [4.2], '6': [6.1, 6.3] });
+    });
+
+    it('should use `_.identity` when `iteratee` is nullish', () => {
+        const array = [6, 4, 6],
+            values = [, null, undefined],
+            expected = lodashStable.map(values, lodashStable.constant({ '4': [4], '6': [6, 6] }));
+
+        const actual = lodashStable.map(values, (value, index) =>
+            index ? groupBy(array, value) : groupBy(array),
+        );
+
+        assert.deepStrictEqual(actual, expected);
+    });
+
+    it('should work with `_.property` shorthands', () => {
+        const actual = groupBy(['one', 'two', 'three'], 'length');
+        assert.deepStrictEqual(actual, { '3': ['one', 'two'], '5': ['three'] });
+    });
+
+    it('should only add values to own, not inherited, properties', () => {
+        const actual = groupBy(array, (n) =>
+            Math.floor(n) > 4 ? 'hasOwnProperty' : 'constructor',
+        );
+
+        assert.deepStrictEqual(actual.constructor, [4.2]);
+        assert.deepStrictEqual(actual.hasOwnProperty, [6.1, 6.3]);
+    });
+
+    it('should work with a number for `iteratee`', () => {
+        const array = [
+            [1, 'a'],
+            [2, 'a'],
+            [2, 'b'],
+        ];
+
+        assert.deepStrictEqual(groupBy(array, 0), {
+            '1': [[1, 'a']],
+            '2': [
+                [2, 'a'],
+                [2, 'b'],
+            ],
+        });
+        assert.deepStrictEqual(groupBy(array, 1), {
+            a: [
+                [1, 'a'],
+                [2, 'a'],
+            ],
+            b: [[2, 'b']],
+        });
+    });
+
+    it('should work with an object for `collection`', () => {
+        const actual = groupBy({ a: 6.1, b: 4.2, c: 6.3 }, Math.floor);
+        assert.deepStrictEqual(actual, { '4': [4.2], '6': [6.1, 6.3] });
+    });
+
+    it('should work in a lazy sequence', () => {
+        const array = lodashStable
+            .range(LARGE_ARRAY_SIZE)
+            .concat(
+                lodashStable.range(Math.floor(LARGE_ARRAY_SIZE / 2), LARGE_ARRAY_SIZE),
+                lodashStable.range(Math.floor(LARGE_ARRAY_SIZE / 1.5), LARGE_ARRAY_SIZE),
+            );
+
+        const iteratee = function (value) {
+                value.push(value[0]);
+                return value;
+            },
+            predicate = function (value) {
+                return isEven(value[0]);
+            },
+            actual = _(array).groupBy().map(iteratee).filter(predicate).take().value();
+
+        assert.deepEqual(
+            actual,
+            _.take(_.filter(lodashStable.map(groupBy(array), iteratee), predicate)),
+        );
+    });
+});