test(common): Improve coverage for utility functions

src/common/utils/includes.js

@@ -1,5 +1,4 @@
 /**
- * Includes item
  * @param {array|string} items
  * @param {array|string} item
  * @returns {boolean}

src/common/utils/index.js

@@ -1,21 +1,8 @@
-import capitalize from './capitalize';
-import includes from './includes';
-import isNil from './is-nil';
-import isObject from './is-object';
-import omitNil from './omit-nil';
-import omitProperty from './omit-property';
-import toNumber from './to-number';
-import toSnakeCase from './to-snake-case';
-import toString from './to-string';
-
-export {
-    capitalize,
-    includes,
-    isNil,
-    isObject,
-    omitNil,
-    omitProperty,
-    toNumber,
-    toSnakeCase,
-    toString,
-};
+export { default as includes } from './includes';
+export { default as isNil } from './is-nil';
+export { default as isObject } from './is-object';
+export { default as omitNil } from './omit-nil';
+export { default as omitProperty } from './omit-property';
+export { default as toNumber } from './to-number';
+export { default as toSnakeCase } from './to-snake-case';
+export { default as toString } from './to-string';

src/common/utils/is-nil.js

@@ -1,5 +1,4 @@
 /**
- * Is nil
  * @param {*} value
  * @returns {boolean}
  */

src/common/utils/is-object.js

@@ -1,10 +1,7 @@
 /**
- * Is object
  * @param {*} value
  * @returns {boolean}
  */
 export default function isObject(value) {
-    const type = typeof value;
-
-    return value !== null && (type === 'object' || type === 'function');
+    return value !== null && typeof value === 'object' && !Array.isArray(value);
 }

src/common/utils/omit-nil.js

@@ -2,7 +2,6 @@ import isNil from './is-nil';
 import omitProperty from './omit-property';
 
 /**
- * Omit nil
  * @param {Object} object
  * @returns {Object}
  */

src/common/utils/omit-property.js

@@ -1,7 +1,6 @@
 import isObject from './is-object';
 
 /**
- * Omit property
  * @param {Object} object
  * @param {Function} predicateFn
  * @returns {Object}

src/common/utils/to-number.js

@@ -1,5 +1,4 @@
 /**
- * To number
  * @param {*} value
  * @returns {number}
  */

src/common/utils/to-snake-case.js

@@ -1,10 +1,9 @@
 /**
- * To snake case
  * @param {string} string
  * @returns {string}
  */
 export default function toSnakeCase(string) {
-    if (!string) {
+    if (typeof string !== 'string') {
         return string;
     }
 

src/common/utils/to-string.js

@@ -1,5 +1,4 @@
 /**
- * To string
  * @param {*} value
  * @returns {string}
  */

test/common/utils/includes.spec.js

@@ -0,0 +1,23 @@
+import includes from '../../../src/common/utils/includes';
+
+describe('includes', () => {
+    it('returns true if the array contains the item', () => {
+        expect(includes([1, 2, 3], 2)).toEqual(true);
+    });
+
+    it('returns false if the array does not contain the item', () => {
+        expect(includes([1, 2, 3], 4)).toEqual(false);
+    });
+
+    it('returns true if the string contains the substring', () => {
+        expect(includes('hello world', 'lo')).toEqual(true);
+    });
+
+    it('returns false if the string does not contain the substring', () => {
+        expect(includes('hello world', 'la')).toEqual(false);
+    });
+
+    it('returns false if the parameter is not a string or array', () => {
+        expect(includes({ la: 'la' }, 'la')).toEqual(false);
+    });
+});

test/common/utils/is-nil.spec.js

@@ -1,19 +1,19 @@
 import isNil from '../../../src/common/utils/is-nil';
 
 describe('isNil', () => {
-    it('should return true if value is null', () => {
+    it('returns true if the input value is null', () => {
         expect(isNil(null)).toBeTruthy();
     });
 
-    it('should return true if value is undefined', () => {
+    it('returns true if the input value is undefined', () => {
         expect(isNil(undefined)).toBeTruthy();
     });
 
-    it('should return false if value is empty', () => {
+    it('returns false if the input value is empty', () => {
         expect(isNil('')).toBeFalsy();
     });
 
-    it('should return false if value is not empty', () => {
+    it('returns false if the input value is not empty', () => {
         expect(isNil('foobar')).toBeFalsy();
     });
 });

test/common/utils/omit-property.spec.js

@@ -1,15 +1,22 @@
 import omitProperty from '../../../src/common/utils/omit-property';
 
 describe('omitProperty', () => {
-    it('should omit property if matching predicate', () => {
+    it('omits the property if its key matches the predicate', () => {
         const output = omitProperty({ a: 'a', b: 'b' }, value => value === 'b');
 
         expect(output).toEqual({ a: 'a' });
     });
 
-    it('should not omit property if matching predicate', () => {
+    it('does not omit the property if its key does not match the predicate', () => {
         const output = omitProperty({ a: 'a', b: 'b' }, value => value === 'c');
 
         expect(output).toEqual({ a: 'a', b: 'b' });
     });
+
+    it('returns the parameter if it is not an object', () => {
+        const input = ['a', 'b'];
+        const output = omitProperty(input, value => value === 'b');
+
+        expect(output).toEqual(input);
+    });
 });

test/common/utils/to-number.spec.js

@@ -0,0 +1,11 @@
+import toNumber from '../../../src/common/utils/to-number';
+
+describe('toNumber', () => {
+    it('converts the number-like string into a number', () => {
+        expect(toNumber('1.5')).toEqual(1.5);
+    });
+
+    it('returns 0 if the parameter is not a number-like string', () => {
+        expect(toNumber('foobar')).toEqual(0);
+    });
+});

test/common/utils/to-snake-case.spec.js

@@ -0,0 +1,17 @@
+import toSnakeCase from '../../../src/common/utils/to-snake-case';
+
+describe('toSnakeCase', () => {
+    it('converts a string written in camel case into snake case', () => {
+        expect(toSnakeCase('toSnakeCase')).toEqual('to_snake_case');
+    });
+
+    it('converts a regular string into snake case', () => {
+        expect(toSnakeCase('To snake case')).toEqual('to_snake_case');
+    });
+
+    it('returns the parameter if it is not a string', () => {
+        const input = { message: 'To snake case' };
+
+        expect(toSnakeCase(input)).toEqual(input);
+    });
+});

test/common/utils/to-string.spec.js

@@ -0,0 +1,15 @@
+import toString from '../../../src/common/utils/to-string';
+
+describe('toString', () => {
+    it('converts the number into a string', () => {
+        expect(toString(1)).toEqual('1');
+    });
+
+    it('returns the parameter if it is already a string', () => {
+        expect(toString('foobar')).toEqual('foobar');
+    });
+
+    it('returns a blank string if the parameter is an object', () => {
+        expect(toString({ foobar: 'foobar' })).toEqual('');
+    });
+});