Bug 1026782 Implements MozLoopService.setLoopCharPref. r=ttaubert

browser/components/loop/MozLoopAPI.jsm

@@ -132,6 +132,24 @@ function injectLoopAPI(targetWindow) {
       }
     },
 
+    /**
+     * Set any character preference under "loop."
+     *
+     * @param {String} prefName The name of the pref without the preceding "loop."
+     * @param {String} stringValue The value to set.
+     *
+     * Any errors thrown by the Mozilla pref API are logged to the console
+     * and cause false to be returned.
+     */
+    setLoopCharPref: {
+      enumerable: true,
+      configurable: true,
+      writable: true,
+      value: function(prefName, value) {
+        MozLoopService.setLoopCharPref(prefName, value);
+      }
+    },
+
     /**
      * Return any preference under "loop." that's coercible to a character
      * preference.

browser/components/loop/MozLoopService.jsm

@@ -443,6 +443,23 @@ this.MozLoopService = {
     }
   },
 
+  /**
+   * Set any character preference under "loop.".
+   *
+   * @param {String} prefName The name of the pref without the preceding "loop."
+   * @param {String} value The value to set.
+   *
+   * Any errors thrown by the Mozilla pref API are logged to the console.
+   */
+  setLoopCharPref: function(prefName, value) {
+    try {
+      Services.prefs.setCharPref("loop." + prefName, value);
+    } catch (ex) {
+      console.log("setLoopCharPref had trouble setting " + prefName +
+        "; exception: " + ex);
+    }
+  },
+
   /**
    * Return any preference under "loop." that's coercible to a character
    * preference.

browser/components/loop/test/xpcshell/test_loopservice_set_loop_char_pref.js

@@ -0,0 +1,49 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+/*global XPCOMUtils, Services, Assert */
+
+var fakePrefName = "color";
+var fakePrefValue = "green";
+
+function test_setLoopCharPref()
+{
+  Services.prefs.setCharPref("loop." + fakePrefName, "red");
+  MozLoopService.setLoopCharPref(fakePrefName, fakePrefValue);
+
+  var returnedPref = Services.prefs.getCharPref("loop." + fakePrefName);
+
+  Assert.equal(returnedPref, fakePrefValue,
+    "Should set a char pref under the loop. branch");
+  Services.prefs.clearUserPref("loop." + fakePrefName);
+}
+
+function test_setLoopCharPref_new()
+{
+  Services.prefs.clearUserPref("loop." + fakePrefName);
+  MozLoopService.setLoopCharPref(fakePrefName, fakePrefValue);
+
+  var returnedPref = Services.prefs.getCharPref("loop." + fakePrefName);
+
+  Assert.equal(returnedPref, fakePrefValue,
+               "Should set a new char pref under the loop. branch");
+  Services.prefs.clearUserPref("loop." + fakePrefName);
+}
+
+function test_setLoopCharPref_non_coercible_type()
+{
+  MozLoopService.setLoopCharPref(fakePrefName, true);
+
+  ok(true, "Setting non-coercible type should not fail");
+}
+
+
+function run_test()
+{
+  test_setLoopCharPref();
+  test_setLoopCharPref_new();
+  test_setLoopCharPref_non_coercible_type();
+
+  do_register_cleanup(function() {
+    Services.prefs.clearUserPref("loop." + fakePrefName);
+  });
+}

browser/components/loop/test/xpcshell/xpcshell.ini

@@ -7,6 +7,7 @@ firefox-appdir = browser
 [test_loopservice_dnd.js]
 [test_loopservice_expiry.js]
 [test_loopservice_get_loop_char_pref.js]
+[test_loopservice_set_loop_char_pref.js]
 [test_loopservice_initialize.js]
 [test_loopservice_locales.js]
 [test_loopservice_registration.js]