Merge remote-tracking branch 'origin/master' into 2_0_0

Conflicts:
	lib/less/index.js
	lib/less/parser/parser.js
	lib/less/tree/rule.js
	test/less/property-name-interp.less

lib/less/index.js

@@ -21,14 +21,14 @@ less.render = function (input, options, callback) {
             }
             catch (err) { callback(err); return; }
             callback(null, css);
-        });
+            }, options);
     } else {
         return new PromiseConstructor(function (resolve, reject) {
             parser.parse(input, function (e, root) {
                 if (e) { return reject(e); }
                 try { resolve(root.toCSS(options)); }
                 catch (err) { reject( err); }
-            });
+                }, options);
         });
     }
 };

lib/less/parser/parser.js

@@ -1173,6 +1173,7 @@ var Parser = function Parser(env) {
                         value = this.detachedRuleset();
                     }
 
+                    parserInput.commentStore.length = 0;
                     if (!value) {
                         // a name returned by this.ruleProperty() is always an array of the form:
                         // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
@@ -1433,6 +1434,8 @@ var Parser = function Parser(env) {
                         break;
                 }
 
+                parserInput.commentStore.length = 0;
+
                 if (hasIdentifier) {
                     value = this.entity();
                     if (!value) {

lib/less/tree/rule.js

@@ -2,7 +2,7 @@ var Node = require("./node.js"),
     Value = require("./value.js"),
     Keyword = require("./keyword.js");
 
-var Rule = function (name, value, important, merge, index, currentFileInfo, inline) {
+var Rule = function (name, value, important, merge, index, currentFileInfo, inline, variable) {
     this.name = name;
     this.value = (value instanceof Node) ? value : new(Value)([value]); //value instanceof tree.Value || value instanceof tree.Ruleset ??
     this.important = important ? ' ' + important.trim() : '';
@@ -10,7 +10,8 @@ var Rule = function (name, value, important, merge, index, currentFileInfo, inli
     this.index = index;
     this.currentFileInfo = currentFileInfo;
     this.inline = inline || false;
-    this.variable = name.charAt && (name.charAt(0) === '@');
+    this.variable = (variable !== undefined) ? variable
+        : (name.charAt && (name.charAt(0) === '@'));
 };
 
 function evalName(env, name) {
@@ -37,13 +38,14 @@ Rule.prototype.genCSS = function (env, output) {
     output.add(this.important + ((this.inline || (env.lastRule && env.compress)) ? "" : ";"), this.currentFileInfo, this.index);
 };
 Rule.prototype.eval = function (env) {
-    var strictMathBypass = false, name = this.name, evaldValue;
+    var strictMathBypass = false, name = this.name, evaldValue, variable = this.variable;
     if (typeof name !== "string") {
         // expand 'primitive' name directly to get
         // things faster (~10% for benchmark.less):
         name = (name.length === 1)
             && (name[0] instanceof Keyword)
                 ? name[0].value : evalName(env, name);
+            variable = false; // never treat expanded interpolation as new variable name
     }
     if (name === "font" && !env.strictMath) {
         strictMathBypass = true;
@@ -61,7 +63,8 @@ Rule.prototype.eval = function (env) {
                           evaldValue,
                           this.important,
                           this.merge,
-                          this.index, this.currentFileInfo, this.inline);
+                          this.index, this.currentFileInfo, this.inline,
+                              variable);
     }
     catch(e) {
         if (typeof e.index !== 'number') {