Bug 760448 - Send result to CommonUtils.jsonSave's callback; r=rnewman

services/common/tests/unit/test_utils_json.js

@@ -11,7 +11,9 @@ function run_test() {
 
 add_test(function test_roundtrip() {
   _("Do a simple write of an array to json and read");
-  CommonUtils.jsonSave("foo", {}, ["v1", "v2"], ensureThrows(function() {
+  CommonUtils.jsonSave("foo", {}, ["v1", "v2"], ensureThrows(function(error) {
+    do_check_eq(error, null);
+
     CommonUtils.jsonLoad("foo", {}, ensureThrows(function(val) {
       let foo = val;
       do_check_eq(typeof foo, "object");
@@ -25,7 +27,9 @@ add_test(function test_roundtrip() {
 
 add_test(function test_string() {
   _("Try saving simple strings");
-  CommonUtils.jsonSave("str", {}, "hi", ensureThrows(function() {
+  CommonUtils.jsonSave("str", {}, "hi", ensureThrows(function(error) {
+    do_check_eq(error, null);
+
     CommonUtils.jsonLoad("str", {}, ensureThrows(function(val) {
       let str = val;
       do_check_eq(typeof str, "string");
@@ -39,7 +43,9 @@ add_test(function test_string() {
 
 add_test(function test_number() {
   _("Try saving a number");
-  CommonUtils.jsonSave("num", {}, 42, ensureThrows(function() {
+  CommonUtils.jsonSave("num", {}, 42, ensureThrows(function(error) {
+    do_check_eq(error, null);
+
     CommonUtils.jsonLoad("num", {}, ensureThrows(function(val) {
       let num = val;
       do_check_eq(typeof num, "number");

services/common/utils.js

@@ -390,6 +390,9 @@ let CommonUtils = {
    *        function, it'll be used as the object to make a json string.
    * @param callback
    *        Function called when the write has been performed. Optional.
+   *        The first argument will be a Components.results error
+   *        constant on error or null if no error was encountered (and
+   *        the file saved successfully).
    */
   jsonSave: function jsonSave(filePath, that, obj, callback) {
     let path = filePath + ".json";
@@ -405,7 +408,8 @@ let CommonUtils = {
     let is = this._utf8Converter.convertToInputStream(out);
     NetUtil.asyncCopy(is, fos, function (result) {
       if (typeof callback == "function") {
-        callback.call(that);
+        let error = (result == Cr.NS_OK) ? null : result;
+        callback.call(that, error);
       }
     });
   },