fix: support prepared commit message (#122)

* fix: support passed commit message

When used as a git hook, using git commit -m'my message' was not making use of 'my message'. Now it does.

* style: Array destructuring and import order

* style: remove whitespace

* test: add tests for prepared commit

Co-authored-by: Leonardo Correa <leonardoanalista@gmail.com>

questions.js

@@ -1,3 +1,4 @@
+const fs = require('fs');
 const _ = require('lodash');
 const buildCommit = require('./buildCommit');
 const log = require('./logger');
@@ -18,6 +19,27 @@ const isValidateTicketNo = (value, config) => {
   return true;
 };
 
+const getPreparedCommit = context => {
+  let message = null;
+  if (fs.existsSync('./.git/COMMIT_EDITMSG')) {
+    let preparedCommit = fs.readFileSync('./.git/COMMIT_EDITMSG', 'utf-8');
+    preparedCommit = preparedCommit
+      .replace(/^#.*/gm, '')
+      .replace(/^\s*[\r\n]/gm, '')
+      .replace(/[\r\n]$/, '')
+      .split(/\r\n|\r|\n/);
+
+    if (preparedCommit.length && preparedCommit[0]) {
+      if (context === 'subject') [message] = preparedCommit;
+      else if (context === 'body' && preparedCommit.length > 1) {
+        preparedCommit.shift();
+        message = preparedCommit.join('|');
+      }
+    }
+  }
+  return message;
+};
+
 module.exports = {
   getQuestions(config, cz) {
     // normalize config optional options
@@ -110,6 +132,7 @@ module.exports = {
         type: 'input',
         name: 'subject',
         message: messages.subject,
+        default: getPreparedCommit('subject'),
         validate(value) {
           const limit = config.subjectLimit || 100;
           if (value.length > limit) {
@@ -127,6 +150,7 @@ module.exports = {
         type: 'input',
         name: 'body',
         message: messages.body,
+        default: getPreparedCommit('body'),
       },
       {
         type: 'input',

spec/questionsSpec.js

@@ -1,3 +1,5 @@
+/* eslint-disable nada/path-case */
+const fs = require('fs');
 const questions = require('../questions.js');
 
 describe('cz-customizable', () => {
@@ -62,6 +64,7 @@ describe('cz-customizable', () => {
     // question 5 - SUBJECT
     expect(getQuestion(5).name).toEqual('subject');
     expect(getQuestion(5).type).toEqual('input');
+    expect(getQuestion(5).default).toEqual(null);
     expect(getQuestion(5).message).toMatch(/IMPERATIVE tense description/);
     expect(getQuestion(5).filter('Subject')).toEqual('subject');
     expect(getQuestion(5).validate('bad subject that exceed limit for 6 characters')).toEqual('Exceed limit: 40');
@@ -70,6 +73,7 @@ describe('cz-customizable', () => {
     // question 6 - BODY
     expect(getQuestion(6).name).toEqual('body');
     expect(getQuestion(6).type).toEqual('input');
+    expect(getQuestion(6).default).toEqual(null);
 
     // question 7 - BREAKING CHANGE
     expect(getQuestion(7).name).toEqual('breaking');
@@ -260,4 +264,42 @@ describe('cz-customizable', () => {
       });
     });
   });
+
+  describe('commit already prepared', () => {
+    let existsSync;
+    let readFileSync;
+
+    beforeEach(() => {
+      config = {};
+      existsSync = spyOn(fs, 'existsSync');
+      readFileSync = spyOn(fs, 'readFileSync');
+    });
+
+    it('should ignore if there is no prepared commit file', () => {
+      existsSync.andReturn(false);
+      expect(getQuestion(5).default).toEqual(null);
+      expect(getQuestion(6).default).toEqual(null);
+    });
+
+    it('should ignore an empty prepared commit', () => {
+      existsSync.andReturn(true);
+      readFileSync.andReturn('');
+      expect(getQuestion(5).default).toEqual(null);
+      expect(getQuestion(6).default).toEqual(null);
+    });
+
+    it('should take a single line commit as the subject', () => {
+      existsSync.andReturn(true);
+      readFileSync.andReturn('my commit');
+      expect(getQuestion(5).default).toEqual('my commit');
+      expect(getQuestion(6).default).toEqual(null);
+    });
+
+    it('should split multi line commit between the subject and the body', () => {
+      existsSync.andReturn(true);
+      readFileSync.andReturn('my commit\nmessage\n\nis on several lines');
+      expect(getQuestion(5).default).toEqual('my commit');
+      expect(getQuestion(6).default).toEqual(`message|is on several lines`);
+    });
+  });
 });