feat: implement subject feedback, scope filtering, subject filtering and config through package.json

cz-conventional-changelog can now have its values (specifically all the defaults and maxLineWidth)
through the config.commitizen key in the package.json file.  The scope now automatically becomes
lowercase (as is required for conventional changelogs) and is prompted on the same line (as it is
always short and doesn't need an additional line). The subject question now indicates the total
number of characters that are allowed based upon the maxLineWidth configuration (or 100 as it is now
by default), the length of the type, and scope. Validation prevents entering more than the allowed
number of characters with feedback of the number of characters entered.  Subject will always have a
lowercase first letter and strip any trailing dots (as is required by the conventional changelog
standard).  'commitizen' and 'semantic-release' have been updated to the most recent versions
(because of current vunderabilites) and the .travisci file has been updated to reflect newer node
versions.

Author: yinzara

.travis.yml

@@ -1,18 +1,21 @@
-sudo: false
 language: node_js
-cache:
-  directories:
-    - node_modules
-notifications:
-  email: false
+
 node_js:
-  - '4'
-before_install:
-  - npm i -g npm@^2.0.0
-before_script:
-  - npm prune
-after_success:
-  - npm run semantic-release
+  - 10
+  - 8
+  - 6
+
+jobs:
+  include:
+    - stage: release
+      node_js: lts/*
+      script: skip
+      deploy:
+        provider: script
+        skip_cleanup: true
+        script:
+          - npm semantic-release
+
 branches:
   only:
-    - master
+    - master

README.md

@@ -6,3 +6,28 @@ Status:
 [![Build Status](https://img.shields.io/travis/commitizen/cz-conventional-changelog.svg?style=flat-square)](https://travis-ci.org/commitizen/cz-conventional-changelog)
 
 Part of the [commitizen](https://github.com/commitizen/cz-cli) family. Prompts for [conventional changelog](https://github.com/conventional-changelog/conventional-changelog) standard.
+
+## Configuration
+
+Like commitizen, you specify the configuration of cz-conventional-changelog through the package.json's `config.commitizen` key.
+
+### package.json
+```json5
+{
+// ...  default values
+    "config": {
+        "commitizen": {      
+            "path": "./node_modules/cz-conventional-changelog",
+            "maxHeaderWidth": 100,
+            "maxLineWidth": 100,
+            "defaultType": "",
+            "defaultScope": "",        
+            "defaultSubject": "",
+            "defaultBody": "",
+            "defaultIssues": ""
+        }
+    }
+// ...    
+}
+
+``` 

engine.js

@@ -4,13 +4,32 @@ var wrap = require('word-wrap');
 var map = require('lodash.map');
 var longest = require('longest');
 var rightPad = require('right-pad');
+var chalk = require('chalk')
 
 var filter = function(array) {
   return array.filter(function(x) {
     return x;
   });
 };
 
+var headerLength = function(answers) {
+  return answers.type.length + 2 + (answers.scope ? answers.scope.length + 2 : 0)
+}
+
+var maxSummaryLength = function(options, answers) {
+  return options.maxHeaderWidth - headerLength(answers)
+}
+var filterSubject = function(subject) {
+  subject = subject.trim();
+  if (subject.charAt(0).toLowerCase() !== subject.charAt(0)) {
+    subject = subject.charAt(0).toLowerCase() + subject.slice(1, subject.length);
+  }
+  while (subject.endsWith('.')) {
+    subject = subject.slice(0, subject.length - 1)
+  }
+  return subject
+}
+
 // This can be any kind of SystemJS compatible module.
 // We use Commonjs here, but ES6 or AMD would do just
 // fine.
@@ -26,6 +45,7 @@ module.exports = function (options) {
     };
   });
 
+
   return {
     // When a user runs `git cz`, prompter will
     // be executed. We pass you cz, which currently
@@ -39,7 +59,7 @@ module.exports = function (options) {
     // By default, we'll de-indent your commit
     // template and will keep empty lines.
     prompter: function(cz, commit) {
-      console.log('\nLine 1 will be cropped at 100 characters. All other lines will be wrapped after 100 characters.\n');
+      console.log('\nLine 1 will have the maximum length of ' + options.maxHeaderWidth + ' characters (enforced). All other lines will be wrapped after ' + options.maxLineWidth + ' characters.\n');
 
       // Let's ask some questions of the user
       // so that we can populate our commit
@@ -58,13 +78,32 @@ module.exports = function (options) {
         }, {
           type: 'input',
           name: 'scope',
-          message: 'What is the scope of this change (e.g. component or file name)? (press enter to skip)\n',
-          default: options.defaultScope
+          message: 'What is the scope of this change (e.g. component or file name): (press enter to skip)',
+          default: options.defaultScope,
+          filter: function(value) {
+            return value.trim().toLowerCase();
+          }
         }, {
           type: 'input',
           name: 'subject',
-          message: 'Write a short, imperative tense description of the change:\n',
-          default: options.defaultSubject
+          message: function (answers) {
+            return 'Write a short, imperative tense description of the change (max ' + maxSummaryLength(options, answers) + ' chars):\n'
+          },
+          default: options.defaultSubject,
+          validate: function(subject, answers) {
+            var filteredSubject = filterSubject(subject)
+            return filteredSubject.length == 0 ? 'Subject is required' :
+                filteredSubject.length <= maxSummaryLength(options, answers) ? true :
+                'Subject length must be less than or equal to ' + maxSummaryLength(options, answers) + ' characters. Current length is ' + filteredSubject.length + ' characters.';
+          },
+          transformer: function(subject, answers) {
+            var filteredSubject = filterSubject(subject)
+            var color = filteredSubject.length <= maxSummaryLength(options, answers) ? chalk.green : chalk.red
+            return color('(' + filteredSubject.length + ') ' + subject)
+          },
+          filter: function(subject) {
+            return filterSubject(subject)
+          }
         }, {
           type: 'input',
           name: 'body',
@@ -98,35 +137,30 @@ module.exports = function (options) {
         }
       ]).then(function(answers) {
 
-        var maxLineWidth = 100;
-
         var wrapOptions = {
           trim: true,
           newline: '\n',
           indent:'',
-          width: maxLineWidth
+          width: options.maxLineWidth
         };
 
         // parentheses are only needed when a scope is present
-        var scope = answers.scope.trim();
-        scope = scope ? '(' + answers.scope.trim() + ')' : '';
+        var scope = answers.scope ? '(' + answers.scope + ')' : '';
 
-        // Hard limit this line
-        var head = (answers.type + scope + ': ' + answers.subject.trim()).slice(0, maxLineWidth);
+        // Hard limit this line in the validate
+        var head = answers.type + scope + ': ' + answers.subject;
 
-        // Wrap these lines at 100 characters
-        var body = wrap(answers.body, wrapOptions);
+        // Wrap these lines at 72 characters
+        var body = answers.body ? wrap(answers.body, wrapOptions) : false;
 
         // Apply breaking change prefix, removing it if already present
         var breaking = answers.breaking ? answers.breaking.trim() : '';
         breaking = breaking ? 'BREAKING CHANGE: ' + breaking.replace(/^BREAKING CHANGE: /, '') : '';
-        breaking = wrap(breaking, wrapOptions);
-
-        var issues = answers.issues ? wrap(answers.issues, wrapOptions) : '';
+        breaking = breaking ? wrap(breaking, wrapOptions) : false;
 
-        var footer = filter([ breaking, issues ]).join('\n\n');
+        var issues = answers.issues ? wrap(answers.issues, wrapOptions) : false;
 
-        commit(head + '\n\n' + body + '\n\n' + footer);
+        commit(filter([ head, body, breaking, issues ]).join('\n\n'));
       });
     }
   };

index.js

@@ -2,12 +2,17 @@
 
 var engine = require('./engine');
 var conventionalCommitTypes = require('conventional-commit-types');
+var configLoader = require('commitizen').configLoader
+
+var config = configLoader.load()
 
 module.exports = engine({
   types: conventionalCommitTypes.types,
-  defaultType: process.env.CZ_TYPE,
-  defaultScope: process.env.CZ_SCOPE,
-  defaultSubject: process.env.CZ_SUBJECT,
-  defaultBody: process.env.CZ_BODY,
-  defaultIssues: process.env.CZ_ISSUES
+  defaultType: process.env.CZ_TYPE || config.defaultType,
+  defaultScope: process.env.CZ_SCOPE || config.defaultScope,
+  defaultSubject: process.env.CZ_SUBJECT || config.defaultSubject,
+  defaultBody: process.env.CZ_BODY || config.defaultBody,
+  defaultIssues: process.env.CZ_ISSUES || config.defaultIssues,
+  maxHeaderWidth: process.env.CZ_MAX_LINE_WIDTH || config.maxHeaderWidth || 100,
+  maxLineWidth: process.env.CZ_MAX_BODY_WIDTH || config.maxLineWidth || 100,
 });