feat: require Node.js 6

BREAKING CHANGE: remove support for Node.js < 6

Author: pvdlg

.travis.yml

@@ -1,10 +1,9 @@
 language: node_js
 
 node_js:
-  - 9
+  - 10
   - 8
   - 6
-  - 4
 
 branches:
   only:

lib/format-commit.js

@@ -36,7 +36,7 @@ module.exports = (answers, options, config) => {
 	};
 	// Parentheses are only needed when a scope is present
 	const scope = answers.scope ? answers.scope.trim() : '';
-	const isAlias = !Object.prototype.hasOwnProperty.call(options.types, answers.type);
+	const isAlias = !Reflect.apply(Object.prototype.hasOwnProperty, options.types, [answers.type]);
 	const type = isAlias ? options.aliases[answers.type].type : answers.type;
 	const emoji = config.emoji ? (isAlias ? options.aliases[answers.type].emoji : options.types[type].emoji) : '';
 	// Limit head to maxSubjectLength (including the trailing emoji)

package.json

@@ -25,7 +25,7 @@
     "xo": "^0.21.0"
   },
   "engines": {
-    "node": ">=4"
+    "node": ">=6"
   },
   "files": [
     "lib",
@@ -60,8 +60,6 @@
   },
   "prettier": {
     "printWidth": 120,
-    "singleQuote": true,
-    "bracketSpacing": false,
     "trailingComma": "es5"
   },
   "publishConfig": {