validation draft

Author: mightyaleksey

lib/index.js

@@ -6,6 +6,7 @@ const identity = require('lodash').identity;
 const readFileSync = require('fs').readFileSync;
 const relative = require('path').relative;
 const resolve = require('path').resolve;
+const validate = require('./validate');
 
 const postcss = require('postcss');
 const Values = require('postcss-modules-values');
@@ -27,19 +28,23 @@ module.exports = function setupHook({
   use,
   rootDir: context = process.cwd(),
 }) {
+  validate(arguments[0]);
+
   const tokensByFile = {};
 
-  let scopedName = function () {};
+  let scopedName;
   if (generateScopedName) {
     scopedName = typeof generateScopedName !== 'function'
       ? genericNames(generateScopedName || '[name]__[local]___[hash:base64:5]', {context})
       : generateScopedName;
   } else {
     // small fallback
-    scopedName = (local, filename) => Scope.generateScopedName(local, relative(context, filename));
+    scopedName = (local, filename) => {
+      return Scope.generateScopedName(local, relative(context, filename));
+    };
   }
 
-  const plugins = [
+  const plugins = (use || [
     ...prepend,
     Values,
     mode
@@ -50,7 +55,7 @@ module.exports = function setupHook({
       : ExtractImports,
     new Scope({generateScopedName: scopedName}),
     ...append,
-  ].concat(new Parser({fetch})); // no pushing in order to avoid the possible mutations;
+  ]).concat(new Parser({fetch})); // no pushing in order to avoid the possible mutations;
 
   // https://github.com/postcss/postcss#options
   const runner = postcss(plugins);

lib/validate.js

@@ -0,0 +1,17 @@
+const rules = {
+  // hook
+  extensions:         'array|string',
+  preprocessCss:      'function',
+  processCss:         'function',
+  to:                 'string',
+  // plugins
+  append:             'array',
+  prepend:            'array',
+  use:                'array',
+  createImportedName: 'function',
+  generateScopedName: 'function|string',
+  mode:               'string',
+  rootDir:            'string',
+};
+
+module.exports = function validate(options) {}