Empty string (#152)

* test: add empty string test * Fix empty strings

Author: goto-bus-stop

test/fixtures/prefix-empty-source.js

@@ -0,0 +1,3 @@
+const sf = require('sheetify')
+
+sf``

test/prefix.js

@@ -112,4 +112,31 @@ test('prefix', function (t) {
  }
  }
  })
+
+ t.test('should return a prefix when an empty string is passed', function (t) {
+ t.plan(1)
+
+ const ws = concat(function (buf) {
+ const res = String(buf).trim()
+ t.equal(res, '', 'css is equal')
+ })
+
+ const bOpts = { browserField: false }
+ const bpath = path.join(__dirname, 'fixtures/prefix-empty-source.js')
+ browserify(bpath, bOpts)
+ .transform(sheetify)
+ .transform(function (file) {
+ return through(function (buf, enc, next) {
+ const str = buf.toString('utf8')
+ this.push(str.replace(/sheetify\/insert/, 'insert-css'))
+ next()
+ })
+ })
+ .plugin('css-extract', { out: outFn })
+ .bundle()
+
+ function outFn () {
+ return ws
+ }
+ })
 })

transform.js

@@ -192,7 +192,7 @@ function transform (filename, options) {
  // then replace the AST nodes with new values
  // (obj, fn) -> null
  function iterate (val, done) {
- if (val.css) return handleCss(val)
+ if (typeof val.css === 'string') return handleCss(val)
 
  if (/\.js$/.test(val.filename)) {
  delete require.cache[require.resolve(val.filename)]