Allow generating html given a filename instead of a post

Fixes #5

index.js

@@ -5,7 +5,11 @@ var Ractive = require('ractive')
 var extend = require('xtend')
 Ractive.DEBUG = false
 
-module.exports = function getRenderedPostWithTemplates(post, options, cb) {
+module.exports = getRenderedPostWithTemplates
+
+function getRenderedPostWithTemplates(post, options, cb) {
+	if (typeof post === 'string') return loadFilename(post, options, cb)
+
 	options.data = options.data || {}
 	cb = dezalgo(cb)
 	buildMapOfAllPostDependencies(post, options.linkifier, options.butler.getPost, function(err, mapOfPosts) {
@@ -27,6 +31,16 @@ module.exports = function getRenderedPostWithTemplates(post, options, cb) {
 	})
 }
 
+function loadFilename(filename, options, cb) {
+	options.butler.getPost(filename, function(err, post) {
+		if (err) {
+			cb(err)
+		} else {
+			getRenderedPostWithTemplates(post, options, cb)
+		}
+	})
+}
+
 function getContainedFileNames(ast) {
 	return Object.keys(ast.filter(function(chunk) {
 		return chunk.type === 'template'

readme.md

@@ -31,7 +31,7 @@ butler.getPost('excellent-missive.md', function(err, post) {
 
 # render(post, options, cb)
 
-- `post`: a Noddity post object returned by a Noddity Butler
+- `post`: either a Noddity post object, or the file name of a post to be loaded
 - `options`: all the other arguments
 	- `butler`: a [Noddity Butler](https://www.npmjs.com/package/noddity-butler)
 	- `linkifier`: a [Noddity Linkifier](https://www.npmjs.com/package/noddity-linkifier)

test/test.js

@@ -52,3 +52,18 @@ test('filename starting with a number', function(t) {
 		})
 	})
 })
+
+test('loading based on file name', function(t) {
+	var state = makeTestState()
+
+	state.retrieval.addPost('file1.md', { title: 'Some title', date: new Date() }, 'This is a ::file2.md:: post that I *totally* wrote')
+	state.retrieval.addPost('file2.md', { title: 'Some title', date: new Date() }, 'lol yeah ::herp|wat:: ::herp|huh::')
+	state.retrieval.addPost('herp', { title: 'Some title', date: new Date(), markdown: false }, 'lookit {{1}}')
+
+	state.render('file1.md', {}, function(err, html) {
+		t.notOk(err, 'no error')
+		t.equal(html, '<p>This is a <p>lol yeah lookit wat lookit huh</p> post that I <em>totally</em> wrote</p>')
+		t.end()
+	})
+
+})