Bug 1024054 - Create a previewer for ES6 Symbol. r=past

browser/devtools/shared/widgets/VariablesView.jsm

@@ -3209,6 +3209,7 @@ VariablesView.isPrimitive = function(aDescriptor) {
       type == "-Infinity" ||
       type == "NaN" ||
       type == "-0" ||
+      type == "symbol" ||
       type == "longString") {
     return true;
   }
@@ -3426,6 +3427,11 @@ VariablesView.stringifiers.byType = {
     }
     return null;
   },
+
+  symbol: function(aGrip, aOptions) {
+    const name = aGrip.name || "";
+    return "Symbol(" + name + ")";
+  },
 }; // VariablesView.stringifiers.byType
 
 VariablesView.stringifiers.byObjectClass = {

browser/devtools/webconsole/console-output.js

@@ -1129,6 +1129,7 @@ Messages.Extended.prototype = Heritage.extend(Messages.Simple.prototype,
       "infinity": "cm-atom",
       "null": "cm-atom",
       "undefined": "cm-comment",
+      "symbol": "cm-atom"
     };
 
     let className = map[typeof grip];

browser/devtools/webconsole/test/browser_webconsole_output_01.js

@@ -75,6 +75,24 @@ let inputTests = [
     output: "/foobar/",
     inspectable: true,
   },
+
+  // 9
+  {
+    input: "Symbol()",
+    output: "Symbol()"
+  },
+
+  // 10
+  {
+    input: "Symbol('foo')",
+    output: "Symbol(foo)"
+  },
+
+  // 11
+  {
+    input: "Symbol.iterator",
+    output: "Symbol(Symbol.iterator)"
+  },
 ];
 
 longString = initialString = null;

toolkit/devtools/webconsole/utils.js

@@ -1743,6 +1743,9 @@ function JSTermHelpers(aOwner)
   aOwner.sandbox.print = function JSTH_print(aValue)
   {
     aOwner.helperResult = { rawOutput: true };
+    if (typeof aValue === "symbol") {
+      return Symbol.prototype.toString.call(aValue);
+    }
     // Waiving Xrays here allows us to see a closer representation of the
     // underlying object. This may execute arbitrary content code, but that
     // code will run with content privileges, and the result will be rendered