Require Node.js 6 and update marked

Closes #14

.gitattributes

@@ -1,2 +1 @@
-* text=auto
-*.js text eol=lf
+* text=auto eol=lf

.travis.yml

@@ -1,5 +1,5 @@
 language: node_js
 node_js:
+  - '10'
   - '8'
   - '6'
-  - '4'

package.json

@@ -10,7 +10,7 @@
 		"url": "sindresorhus.com"
 	},
 	"engines": {
-		"node": ">=4"
+		"node": ">=6"
 	},
 	"scripts": {
 		"test": "xo && ava"
@@ -29,12 +29,13 @@
 		"html"
 	],
 	"dependencies": {
-		"marked": "^0.3.9",
-		"plugin-error": "^0.1.2",
+		"marked": "^0.4.0",
+		"plugin-error": "^1.0.1",
 		"through2": "^2.0.0"
 	},
 	"devDependencies": {
 		"ava": "*",
+		"p-event": "^2.1.0",
 		"vinyl": "^2.1.0",
 		"xo": "*"
 	}

test.js

@@ -1,26 +1,26 @@
 import test from 'ava';
 import Vinyl from 'vinyl';
-import m from '.';
+import pEvent from 'p-event';
+import markdown from '.';
 
-test.cb('compiles Markdown to HTML', t => {
-	const stream = m();
-
-	stream.once('data', file => {
-		t.is(file.relative, 'fixture.html');
-		t.is(file.contents.toString(), '<p><em>foo</em></p>\n');
-	});
-
-	stream.on('end', t.end);
+test('compiles Markdown to HTML', async t => {
+	const stream = markdown();
+	const dataPromise = pEvent(stream, 'data');
 
 	stream.end(new Vinyl({
 		path: 'fixture.md',
 		contents: Buffer.from('*foo*')
 	}));
+
+	const file = await dataPromise;
+
+	t.is(file.relative, 'fixture.html');
+	t.is(file.contents.toString(), '<p><em>foo</em></p>\n');
 });
 
 test('exposes the marked object', t => {
-	t.truthy(m.marked);
-	t.truthy(m.marked.Renderer);
-	t.truthy(m.marked.lexer);
-	t.truthy(m.marked.parser);
+	t.truthy(markdown.marked);
+	t.truthy(markdown.marked.Renderer);
+	t.truthy(markdown.marked.lexer);
+	t.truthy(markdown.marked.parser);
 });