wip: code formatting nits continued

test/sampleSize.spec.js

@@ -0,0 +1,73 @@
+import lodashStable from 'lodash';
+import { falsey, empties, stubArray } from './utils';
+import sampleSize from '../src/sampleSize';
+
+describe('sampleSize', () => {
+    const array = [1, 2, 3];
+
+    it('should return an array of random elements', () => {
+        const actual = sampleSize(array, 2);
+
+        expect(actual.length).toBe(2);
+        expect(lodashStable.difference(actual, array)).toEqual([]);
+    });
+
+    it('should contain elements of the collection', () => {
+        const actual = sampleSize(array, array.length).sort();
+
+        expect(actual).toEqual(array);
+    });
+
+    it('should treat falsey `size` values, except `undefined`, as `0`', () => {
+        const expected = lodashStable.map(falsey, (value) => (value === undefined ? ['a'] : []));
+
+        const actual = lodashStable.map(falsey, (size, index) =>
+            index ? sampleSize(['a'], size) : sampleSize(['a']),
+        );
+
+        expect(actual).toEqual(expected);
+    });
+
+    it('should return an empty array when `n` < `1` or `NaN`', () => {
+        lodashStable.each([0, -1, -Infinity], (n) => {
+            expect(sampleSize(array, n)).toEqual([]);
+        });
+    });
+
+    it('should return all elements when `n` >= `length`', () => {
+        lodashStable.each([3, 4, 2 ** 32, Infinity], (n) => {
+            const actual = sampleSize(array, n).sort();
+            expect(actual).toEqual(array);
+        });
+    });
+
+    it('should coerce `n` to an integer', () => {
+        const actual = sampleSize(array, 1.6);
+        expect(actual.length).toBe(1);
+    });
+
+    it('should return an empty array for empty collections', () => {
+        const expected = lodashStable.map(empties, stubArray);
+
+        const actual = lodashStable.transform(empties, (result, value) => {
+            try {
+                result.push(sampleSize(value, 1));
+            } catch (e) {}
+        });
+
+        expect(actual).toEqual(expected);
+    });
+
+    it('should sample an object', () => {
+        const object = { a: 1, b: 2, c: 3 };
+        const actual = sampleSize(object, 2);
+
+        expect(actual.length).toBe(2);
+        expect(lodashStable.difference(actual, lodashStable.values(object))).toEqual([]);
+    });
+
+    it('should work as an iteratee for methods like `_.map`', () => {
+        const actual = lodashStable.map([['a']], sampleSize);
+        expect(actual).toEqual([['a']]);
+    });
+});