feat(tests): add some basic tests and ensure immutability

Signed-off-by: Charlike Mike Reagent <olsten.larck@gmail.com>

Author: Charlike Mike Reagent

.all-contributorsrc

@@ -1,5 +1,5 @@
 {
-  "projectName": "detect-next-version",
+  "projectName": "parse-commit-message",
   "projectOwner": "tunnckoCore",
   "files": [
     "CONTRIBUTORS.md"

.nycrc.json

@@ -3,5 +3,7 @@
   "functions": 0,
   "branches": 0,
   "lines": 0,
-  "exclude": ["test"]
+  "exclude": [
+    "test"
+  ]
 }

CONTRIBUTORS.md

@@ -5,7 +5,7 @@ Thanks goes to these wonderful people ([emoji key](https://github.com/kentcdodds
 
 <!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
 <!-- prettier-ignore -->
-| [<img src="https://avatars3.githubusercontent.com/u/5038030?v=4" width="150px;"/><br /><sub><b>Charlike Mike Reagent</b></sub>](https://i.am.charlike.online)<br />[💬](#question-olstenlarck "Answering Questions") [💻](https://github.com/tunnckoCore/detect-next-version/commits?author=olstenlarck "Code") [📖](https://github.com/tunnckoCore/detect-next-version/commits?author=olstenlarck "Documentation") [👀](#review-olstenlarck "Reviewed Pull Requests") [⚠️](https://github.com/tunnckoCore/detect-next-version/commits?author=olstenlarck "Tests") |
+| [<img src="https://avatars3.githubusercontent.com/u/5038030?v=4" width="150px;"/><br /><sub><b>Charlike Mike Reagent</b></sub>](https://i.am.charlike.online)<br />[💬](#question-olstenlarck "Answering Questions") [💻](https://github.com/tunnckoCore/parse-commit-message/commits?author=olstenlarck "Code") [📖](https://github.com/tunnckoCore/parse-commit-message/commits?author=olstenlarck "Documentation") [👀](#review-olstenlarck "Reviewed Pull Requests") [⚠️](https://github.com/tunnckoCore/parse-commit-message/commits?author=olstenlarck "Tests") |
 | :---: |
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 

src/index.js

@@ -37,7 +37,11 @@ function parse (commitMessage, plugins) {
     footer,
   }
 
-  return arrayify(plugins).reduce((acc, fn) => Object.assign({}, acc, fn(acc)), commit)
+  return arrayify(plugins).reduce((acc, fn) => {
+    const result = fn(Object.assign({}, acc))
+
+    return Object.assign({}, acc, result)
+  }, commit)
 }
 
 /**

test/index.js

@@ -4,8 +4,38 @@
  */
 
 const test = require('mukla')
-const fn = require('../src/index.js')
+const { parse } = require('../src/index.js')
 
-test('foo bar', () => {
-  test.ok(fn)
+test('should .parse method to work correctly', (done) => {
+  const commitMsg1 = `feat(ng-list): Allow custom separator
+bla bla bla
+
+BREAKING CHANGE: some breaking change.
+Thanks @foobar
+`
+
+  const commit = parse(commitMsg1)
+  // => { type: 'feat',
+  //   scope: 'ng-list',
+  //   subject: 'Allow custom separator',
+  //   header: 'feat(ng-list): Allow custom separator',
+  //   body: 'bla bla bla',
+  //   footer: 'BREAKING CHANGE: some breaking change.\nThanks @foobar' }
+
+  test.strictEqual(typeof commit, 'object')
+  test.strictEqual(commit.type, 'feat')
+  test.strictEqual(commit.scope, 'ng-list')
+  test.strictEqual(commit.subject, 'Allow custom separator')
+  test.strictEqual(commit.body, 'bla bla bla')
+  test.strictEqual(commit.header, 'feat(ng-list): Allow custom separator')
+  test.strictEqual(
+    commit.footer,
+    'BREAKING CHANGE: some breaking change.\nThanks @foobar'
+  )
+  done()
+})
+
+test('should .parse throw for invalid commit convention message', (done) => {
+  test.throws(() => parse('foo bar baz'), /invalid commit message/)
+  done()
 })