Allow local data

Details: posthtml#54

lib/index.js

@@ -329,23 +329,26 @@ function walk (opts, nodes) {
     // parse scopes
     if (node.tag === scopes[0]) {
       // handle syntax error
-      if (!node.attrs || !node.attrs.with) {
-        throw new Error(`the "${scopes[0]}" tag must have a "with" attribute`)
+      if (!node.attrs) {
+        throw new Error(`the "${scopes[0]}" tag must have attributes with data or/and a "with" attribute`)
       }
 
-      const target = vm.runInContext(node.attrs.with, ctx)
+      const targetScope = node.attrs.with ? vm.runInContext(node.attrs.with, ctx) : {}
 
       // handle additional syntax errors
-      if (typeof target !== 'object' || Array.isArray(target)) {
+      if (typeof targetScope !== 'object' || Array.isArray(targetScope)) {
         throw new Error('You must provide an object to make scope')
       }
 
-      const keys = Object.keys(target)
+      Object.assign(targetScope, node.attrs)
+      delete targetScope.with
+
+      const keys = Object.keys(targetScope)
 
       // creates a copy of the keys that will be changed within the loop
       const localsBackup = makeLocalsBackup(keys, opts.locals)
 
-      m.push(executeScope(target, opts.locals, node))
+      m.push(executeScope(targetScope, opts.locals, node))
 
       // returns the original keys values that was changed within the loop
       opts.locals = revertBackupedLocals(keys, opts.locals, localsBackup)