Bug 381693 - Allow null targetObj arg to xpcIJSModuleLoader::import().

r=sayrer, src=brendan.

js/src/xpconnect/idl/xpcIJSModuleLoader.idl

@@ -56,18 +56,22 @@ interface xpcIJSModuleLoader : nsISupports
    *
    * Synchronously loads and evaluates the js file located at
    * 'registryLocation' with a new, fully privileged global object.
-   * After loading, looks for a property 'EXPORTED_SYMBOLS' on the
-   * new global object. 'EXPORTED_SYMBOLS' is expected to be an
-   * array of strings identifying properties on the global object.
-   * If present, these properties will be installed as properties on
-   * targetObj, or, if 'targetObj' is not specified, on the caller's
-   * global object.
+   *
+   * If 'targetObj' is specified and equal to null, returns the
+   * module's global object. Otherwise (if 'targetObj' is not
+   * specified, or 'targetObj' is != null) looks for a property
+   * 'EXPORTED_SYMBOLS' on the new global object. 'EXPORTED_SYMBOLS'
+   * is expected to be an array of strings identifying properties on
+   * the global object.  These properties will be installed as
+   * properties on 'targetObj', or, if 'targetObj' is not specified,
+   * on the caller's global object. If 'EXPORTED_SYMBOLS' is not
+   * found, an error is thrown.
    *
    * @param resourceURI A resource:// URI string to load the module from.
    * @param targetObj  the object to install the exported properties on.
-   *        If this parameter is null or is a primitive value, this
-   *        method throws an exception.
-   * @returns the new global object the module code was loaded into.
+   *        If this parameter is a primitive value, this method throws
+   *        an exception.
+   * @returns the module code's global object.
    *
    * The implementation maintains a hash of registryLocation->global obj.
    * Subsequent invocations of importModule with 'registryLocation'

js/src/xpconnect/idl/xpccomponents.idl

@@ -176,18 +176,22 @@ interface nsIXPCComponents_Utils : nsISupports
      *
      * Synchronously loads and evaluates the js file located at
      * 'registryLocation' with a new, fully privileged global object.
-     * After loading, looks for a property 'EXPORTED_SYMBOLS' on the
-     * new global object. 'EXPORTED_SYMBOLS' is expected to be an
-     * array of strings identifying properties on the global object.
-     * If present, these properties will be installed as properties on
-     * targetObj, or, if 'targetObj' is not specified, on the caller's
-     * global object.
+     *
+     * If 'targetObj' is specified and equal to null, returns the
+     * module's global object. Otherwise (if 'targetObj' is not
+     * specified, or 'targetObj' is != null) looks for a property
+     * 'EXPORTED_SYMBOLS' on the new global object. 'EXPORTED_SYMBOLS'
+     * is expected to be an array of strings identifying properties on
+     * the global object.  These properties will be installed as
+     * properties on 'targetObj', or, if 'targetObj' is not specified,
+     * on the caller's global object. If 'EXPORTED_SYMBOLS' is not
+     * found, an error is thrown.
      *
      * @param resourceURI A resource:// URI string to load the module from.
      * @param targetObj  the object to install the exported properties on.
-     *        If this parameter is null or is a primitive value, this
-     *        method throws an exception.
-     * @returns the new global object the module code was loaded into.
+     *        If this parameter is a primitive value, this method throws
+     *        an exception.
+     * @returns the module code's global object.
      *
      * The implementation maintains a hash of registryLocation->global obj.
      * Subsequent invocations of importModule with 'registryLocation'

js/src/xpconnect/loader/mozJSComponentLoader.cpp

@@ -1348,11 +1348,11 @@ mozJSComponentLoader::Import(const nsACString & registryLocation)
         jsval *argv = nsnull;
         rv = cc->GetArgvPtr(&argv);
         NS_ENSURE_SUCCESS(rv, rv);
-        if (JSVAL_IS_PRIMITIVE(argv[1]) ||
-            !JS_ValueToObject(cx, argv[1], &targetObject)) {
+        if (!JSVAL_IS_OBJECT(argv[1])) {
             return ReportOnCaller(cc, ERROR_SCOPE_OBJ,
                                   PromiseFlatCString(registryLocation).get());
         }
+        targetObject = JSVAL_TO_OBJECT(argv[1]);
     } else {
         // Our targetObject is the caller's global object. Find it by
         // walking the calling object's parent chain.

js/src/xpconnect/tests/unit/test_bogus_files.js

@@ -74,5 +74,15 @@ function run_test() {
                   true,
                   "NS_ERROR_ILLEGAL_VALUE");
 
+  // check that we can access modules' global objects even if
+  // EXPORTED_SYMBOLS is missing or ill-formed:
+  do_check_eq(typeof(Components.utils.import("resource://test/bogus_exports_type.jsm",
+                                             null)),
+              "object");
+
+  do_check_eq(typeof(Components.utils.import("resource://test/bogus_element_type.jsm",
+                                             null)),
+              "object");
+
   resProt.setSubstitution("test", null);
 }

js/src/xpconnect/tests/unit/test_import.js

@@ -43,7 +43,17 @@ function run_test() {
   do_check_eq(typeof(scope.XPCOMUtils), "object");
   do_check_eq(typeof(scope.XPCOMUtils.generateModule), "function");
   
-  // try again on the global object
+  // access module's global object directly without importing any
+  // symbols
+  var module = Components.utils.import("resource://gre/modules/XPCOMUtils.jsm",
+                                       null);
+  do_check_eq(typeof(XPCOMUtils), "undefined");
+  do_check_eq(typeof(module), "object");
+  do_check_eq(typeof(module.XPCOMUtils), "object");
+  do_check_eq(typeof(module.XPCOMUtils.generateModule), "function");
+  do_check_true(scope.XPCOMUtils == module.XPCOMUtils);
+
+  // import symbols to our global object
   do_check_eq(typeof(Components.utils.import), "function");
   Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
   do_check_eq(typeof(XPCOMUtils), "object");