test(utils): Adding tests to the utils functions

Author: arthurdenner

jest.config.js

@@ -1,12 +1,13 @@
 const { jest: jestConfig } = require('kcd-scripts/config');
 
 module.exports = Object.assign(jestConfig, {
+  coveragePathIgnorePatterns: ['src/index.d.ts'],
   coverageThreshold: {
     global: {
-      statements: 0,
-      branches: 0,
-      functions: 0,
-      lines: 0,
+      statements: 8,
+      branches: 8,
+      functions: 8,
+      lines: 8,
     },
   },
   testEnvironment: 'node',

package.json

@@ -74,6 +74,7 @@
     "node_modules",
     "coverage",
     "dist",
+    "storybook-static",
     "stories"
   ],
   "repository": {

src/__tests__/utils.test.js

@@ -0,0 +1,145 @@
+import parse from 'date-fns/parse';
+import startOfDay from 'date-fns/start_of_day';
+import localeEn from '../locales/en-US';
+import {
+  formatDate,
+  formatSelectedDate,
+  getToday,
+  isSelectable,
+  moveElementsByN,
+  omit,
+  pick,
+} from '../utils';
+
+const objectTest = { a: 'a', b: 'b', c: 'c' };
+const dateTest = parse('2018-06-21');
+const june14 = parse('2018-06-14');
+const june20 = parse('2018-06-20');
+const june25 = parse('2018-06-25');
+const june28 = parse('2018-06-28');
+
+describe('moveElementsByN', () => {
+  it('should return the same array if `n` is zero', () => {
+    expect(moveElementsByN(0, localeEn.weekdays)).toEqual(localeEn.weekdays);
+  });
+
+  it('should return the correct array if `n` is different than zero', () => {
+    expect(moveElementsByN(3, localeEn.weekdays)).toEqual([
+      'Wednesday',
+      'Thursday',
+      'Friday',
+      'Saturday',
+      'Sunday',
+      'Monday',
+      'Tuesday',
+    ]);
+
+    expect(moveElementsByN(5, localeEn.weekdays)).toEqual([
+      'Friday',
+      'Saturday',
+      'Sunday',
+      'Monday',
+      'Tuesday',
+      'Wednesday',
+      'Thursday',
+    ]);
+  });
+});
+
+describe('omit', () => {
+  it('should return the same object if the array of keys is empty', () => {
+    expect(omit([], objectTest)).toEqual(objectTest);
+  });
+
+  it('should return a new object without the given keys', () => {
+    expect(omit(['a', 'b'], objectTest)).toEqual({ c: 'c' });
+  });
+});
+
+describe('pick', () => {
+  it('should return an empty object if the array of keys is empty', () => {
+    expect(pick([], objectTest)).toEqual({});
+  });
+
+  it('should return a new object with the given keys', () => {
+    expect(pick(['a', 'b'], objectTest)).toEqual({ a: 'a', b: 'b' });
+  });
+});
+
+describe('formatDate', () => {
+  it('should return `undefined` if an invalid date is given', () => {
+    expect(formatDate(null, 'DD/MM/YYYY')).toBe(undefined);
+  });
+
+  it('should format correctly if a valid date is given', () => {
+    expect(formatDate(dateTest, 'DD/MM/YYYY')).toBe('21/06/2018');
+  });
+});
+
+describe('isSelectable', () => {
+  it('should return true if the first date is in the informed range', () => {
+    expect(isSelectable(dateTest, june14, june28)).toBe(true);
+  });
+
+  it('should return false if the first date is not in the informed range', () => {
+    expect(isSelectable(dateTest, june14, june20)).toBe(false);
+  });
+
+  it('should return true if the first date is after the minDate', () => {
+    expect(isSelectable(dateTest, june14, null)).toBe(true);
+  });
+
+  it('should return false if the first date is after the minDate', () => {
+    expect(isSelectable(dateTest, june25, null)).toBe(false);
+  });
+
+  it('should return true if the first date is before the maxDate', () => {
+    expect(isSelectable(dateTest, null, june25)).toBe(true);
+  });
+
+  it('should return false if the first date is before the maxDate', () => {
+    expect(isSelectable(dateTest, null, june14)).toBe(false);
+  });
+
+  it('should return true if we only provide one date to the function', () => {
+    expect(isSelectable(dateTest)).toBe(true);
+  });
+});
+
+describe('getToday', () => {
+  const today = startOfDay(new Date());
+
+  it('should return the correct result if `today` is not selectable', () => {
+    expect(getToday(june14, june28)).toEqual({
+      date: today,
+      selectable: false,
+      selected: false,
+      today: true,
+    });
+  });
+
+  it('should return the correct result if `today` is selectable', () => {
+    expect(getToday(june14)).toEqual({
+      date: today,
+      selectable: true,
+      selected: false,
+      today: true,
+    });
+  });
+});
+
+describe('formatSelectedDate', () => {
+  it('should return an empty string if an invalid date is given', () => {
+    expect(formatSelectedDate(null, 'DD/MM/YYYY')).toBe('');
+  });
+
+  it('should return the correct result if a valid date is given', () => {
+    expect(formatSelectedDate(june14, 'DD/MM/YYYY')).toBe('14/06/2018');
+  });
+
+  it('should return the correct result if a valid array of dates is given', () => {
+    expect(formatSelectedDate([june14, june20], 'DD/MM/YYYY')).toBe(
+      '14/06/2018 - 20/06/2018'
+    );
+  });
+});

src/utils/index.js renamed to src/utils.js

@@ -2,7 +2,7 @@ import format from 'date-fns/format';
 import isBefore from 'date-fns/is_before';
 import startOfDay from 'date-fns/start_of_day';
 
-function isSelectable(date, minDate, maxDate) {
+export const isSelectable = (date, minDate, maxDate) => {
   if (
     (minDate && isBefore(date, minDate)) ||
     (maxDate && isBefore(maxDate, date))
@@ -11,7 +11,7 @@ function isSelectable(date, minDate, maxDate) {
   }
 
   return true;
-}
+};
 
 export const getToday = (minDate, maxDate) => {
   const today = new Date();
@@ -45,8 +45,7 @@ export const pick = (keysToPick, obj) => {
   return newObj;
 };
 
-export const moveElementsByN = (n = 0, arr = []) =>
-  arr.slice(n).concat(arr.slice(0, n));
+export const moveElementsByN = (n, arr) => arr.slice(n).concat(arr.slice(0, n));
 
 export const formatSelectedDate = (selectedDate, dateFormat) => {
   if (!selectedDate) {