Bug 890913 - Parser.jsm: support SpreadExpression r=vporof

devtools/client/debugger/test/mochitest/browser.ini

@@ -337,6 +337,7 @@ skip-if = e10s && debug
 skip-if = e10s && debug
 [browser_dbg_parser-11.js]
 [browser_dbg_parser-function-defaults.js]
+[browser_dbg_parser-spread-expression.js]
 [browser_dbg_parser-template-strings.js]
 skip-if = e10s && debug
 [browser_dbg_pause-exceptions-01.js]

devtools/client/debugger/test/mochitest/browser_dbg_parser-spread-expression.js

@@ -0,0 +1,32 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that spread expressions work both in arrays and function calls.
+ */
+
+"use strict";
+
+function test() {
+  let { Parser, SyntaxTreeVisitor } =
+    Cu.import("resource://devtools/shared/Parser.jsm", {});
+
+  const SCRIPTS = ["[...a]", "foo(...a)"];
+
+  for (let script of SCRIPTS) {
+    info(`Testing spread expression in '${script}'`);
+    let ast = Parser.reflectionAPI.parse(script);
+    let nodes = SyntaxTreeVisitor.filter(ast,
+      e => e.type == "SpreadExpression");
+    ok(nodes && nodes.length === 1, "Found the SpreadExpression node");
+
+    let expr = nodes[0].expression;
+    ok(expr, "The SpreadExpression node has the sub-expression");
+    is(expr.type, "Identifier", "The sub-expression is an Identifier");
+    is(expr.name, "a", "The sub-expression identifier has a correct name");
+  }
+
+  finish();
+}

devtools/shared/Parser.jsm

@@ -8,6 +8,7 @@
 const Cu = Components.utils;
 
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Console.jsm");
 const { require } = Cu.import("resource://devtools/shared/Loader.jsm", {});
 const DevToolsUtils = require("devtools/shared/DevToolsUtils");
 
@@ -1558,14 +1559,37 @@ var SyntaxTreeVisitor = {
       callbacks.onArrayExpression(node);
     }
     for (let element of node.elements) {
-      // TODO: remove the typeof check when support for SpreadExpression is
-      // added (bug 890913).
-      if (element && typeof this[element.type] == "function") {
+      if (element) {
         this[element.type](element, node, callbacks);
       }
     }
   },
 
+  /**
+   * A spread expression.
+   *
+   * interface SpreadExpression <: Expression {
+   *   type: "SpreadExpression";
+   *   expression: Expression;
+   * }
+   */
+  SpreadExpression: function(node, parent, callbacks) {
+    node._parent = parent;
+
+    if (this.break) {
+      return;
+    }
+    if (callbacks.onNode) {
+      if (callbacks.onNode(node, parent) === false) {
+        return;
+      }
+    }
+    if (callbacks.onSpreadExpression) {
+      callbacks.onSpreadExpression(node);
+    }
+    this[node.expression.type](node.expression, node, callbacks);
+  },
+
   /**
    * An object expression. A literal property in an object expression can have
    * either a string or number as its value. Ordinary property initializers
@@ -1936,6 +1960,9 @@ var SyntaxTreeVisitor = {
     this[node.callee.type](node.callee, node, callbacks);
     for (let argument of node.arguments) {
       if (argument) {
+        if (!this[argument.type]) {
+          console.error("Unknown parser object:", argument.type);
+        }
         this[argument.type](argument, node, callbacks);
       }
     }