fix(headerPattern): change how capturing groups works

The first capturing group captures **type**, second captures **scope** and third captures **subject**

README.md

@@ -113,9 +113,9 @@ The maximum subject length.
 
 ##### headerPattern
 
-Type: `regex` Default: `/^(\w*)(\(([\w\$\.\-\* ]*)\))?\: (.*)$/`
+Type: `regex` Default: `/^(\w*)(?:\(([\w\$\.\-\* ]*)\))?\: (.*)$/`
 
-Used to match header pattern.
+Used to match header pattern. The first capturing group captures **type**, second captures **scope** and third captures **subject**
 
 ##### closeKeywords
 

index.js

@@ -6,7 +6,7 @@ var through = require('through2');
 function conventionalCommitsParser(options) {
   options = extend({
     maxSubjectLength: 80,
-    headerPattern: /^(\w*)(\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
+    headerPattern: /^(\w*)(?:\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
     closeKeywords: [
       'close',
       'closes',

lib/parser.js

@@ -28,17 +28,17 @@ function parser(raw, options) {
   }
 
   match = msg.header.match(options.headerPattern);
-  if (!match || !match[1] || !match[4]) {
+  if (!match || !match[1] || !match[3]) {
     return null;
   }
 
-  if (match[4].length > options.maxSubjectLength) {
-    match[4] = match[4].substr(0, options.maxSubjectLength);
+  if (match[3].length > options.maxSubjectLength) {
+    match[3] = match[3].substr(0, options.maxSubjectLength);
   }
 
   msg.type = match[1];
-  msg.scope = match[3];
-  msg.subject = match[4];
+  msg.scope = match[2];
+  msg.subject = match[3];
 
   _.forEach(lines, function(line) {
     var issue;

test/parser.spec.js

@@ -5,7 +5,7 @@ var parser = require('../lib/parser');
 describe('parseRawCommit', function() {
   var options = {
     maxSubjectLength: 80,
-    headerPattern: /^(\w*)(\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
+    headerPattern: /^(\w*)(?:\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
     closeKeywords: [
       'kill',
       'kills',
@@ -21,7 +21,7 @@ describe('parseRawCommit', function() {
 
   var shortSubjectOptions = {
     maxSubjectLength: 10,
-    headerPattern: /^(\w*)(\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
+    headerPattern: /^(\w*)(?:\(([\w\$\.\-\* ]*)\))?\: (.*)$/,
     closeKeywords: [
       'close',
     ],