Supply a Root stringifier

lib/less-parser.js

@@ -2,6 +2,7 @@ import Comment from 'postcss/lib/comment';
 import Import from './import';
 import Parser from 'postcss/lib/parser';
 import Rule from './rule';
+import Root from './root';
 import findExtendRule from './find-extend-rule';
 import isMixinToken from './is-mixin-token';
 import lessTokenizer from './less-tokenize';
@@ -10,6 +11,14 @@ const blockCommentEndPattern = /\*\/$/;
 
 export default class LessParser extends Parser {
 
+  constructor (input) {
+    super(input);
+
+    this.root = new Root();
+    this.current = this.root;
+    this.root.source = { input, start: { line: 1, column: 1 } };
+  }
+
   atrule (token) {
     if (token[1] === '@import') {
       this.import(token);

lib/root.js

@@ -0,0 +1,14 @@
+import PostCssRoot from 'postcss/lib/root';
+import stringify from './less-stringify';
+
+export default class Root extends PostCssRoot {
+  toString (stringifier) {
+    if (!stringifier) {
+      stringifier = {
+        stringify
+      };
+    }
+
+    return super.toString(stringifier);
+  }
+}

test/postcss.spec.js

@@ -62,4 +62,16 @@ describe('#postcss', () => {
         done();
       }).catch(done);
   });
+
+  it('should create its own Root node stringifier (#82)', (done) => {
+    const lessText = '@import "foo.less"';
+
+    postcss()
+      .process(lessText, { syntax: lessSyntax })
+      .then((result) => {
+        expect(result.root.toString()).to.eql(lessText);
+
+        done();
+      }).catch(done);
+  });
 });