wip: code formatting nits continued

test/sum-methods.spec.js

@@ -0,0 +1,33 @@
+import lodashStable from 'lodash';
+import { _, empties, stubZero } from './utils';
+
+describe('sum methods', () => {
+    lodashStable.each(['sum', 'sumBy'], (methodName) => {
+        const array = [6, 4, 2];
+        const func = _[methodName];
+
+        it(`\`_.${methodName}\` should return the sum of an array of numbers`, () => {
+            expect(func(array)).toBe(12);
+        });
+
+        it(`\`_.${methodName}\` should return \`0\` when passing empty \`array\` values`, () => {
+            const expected = lodashStable.map(empties, stubZero);
+
+            const actual = lodashStable.map(empties, (value) => func(value));
+
+            expect(actual).toEqual(expected);
+        });
+
+        it(`\`_.${methodName}\` should skip \`undefined\` values`, () => {
+            expect(func([1, undefined])).toBe(1);
+        });
+
+        it(`\`_.${methodName}\` should not skip \`NaN\` values`, () => {
+            expect(func([1, NaN])).toEqual(NaN);
+        });
+
+        it(`\`_.${methodName}\` should not coerce values to numbers`, () => {
+            expect(func(['1', '2'])).toBe('12');
+        });
+    });
+});