Allow running without plugins

Author: watilde

Makefile

@@ -3,7 +3,7 @@ all: clean lint test
 lint:
 	./node_modules/.bin/jshint *.js
 
-TESTS = opts source-maps source-maps-file stdout stdin config config-all config-wildcard js-config js-config-all invalid warning
+TESTS = opts source-maps source-maps-file stdout stdin config config-all config-wildcard js-config js-config-all invalid warning no-plugin
 
 
 DIFF = diff -q
@@ -83,6 +83,9 @@ test/build/invalid.css: test/in-force-error.css
 test/build/warning.css: test/in-warning.css
 	./bin/postcss --use ./test/dummy-plugin -o $@ $< && echo Warning is OK here....
 
+test/build/no-plugin.css: test/no-plugin.css
+	./bin/postcss ./test/no-plugin.css -o $@ && echo It works without plugins
+
 test/build/config.css: test/in.css
 	./bin/postcss -u postcss-url -c test/config.json -o $@ $<
 	$(DIFF) $@ $(subst build,ref,$@)

index.js

@@ -49,9 +49,6 @@ var argv = require("yargs")
   .help('h')
   .alias('h', 'help')
   .check(function(argv) {
-    if (!argv.use) {
-      throw 'Please specify at least one plugin name.';
-    }
     if (argv._.length && argv.input) {
       throw 'Both positional arguments and --input option used for `input file`: please only use one of them.';
     }
@@ -104,8 +101,10 @@ var plugins = argv.use.map(function(name) {
   if (local) {
     var resolved = resolve.sync(name, {basedir: process.cwd()});
     plugin = require(resolved);
-  } else {
+  } else if (name) {
     plugin = require(name);
+  } else {
+    return null;
   }
   if (name in argv) {
     plugin = plugin(argv[name]);
@@ -136,7 +135,7 @@ var path = require('path');
 var readFile = require('read-file-stdin');
 var path = require('path');
 var postcss = require('postcss');
-var processor = postcss(plugins);
+var processor = plugins[0] ? postcss(plugins) : postcss();
 var mkdirp = require('mkdirp');
 
 // hook for dynamically updating the list of watched files

test/no-plugin.css

@@ -0,0 +1,3 @@
+body {
+  margin: 0;
+}