--- a/layout/tools/reftest/mach_commands.py
+++ b/layout/tools/reftest/mach_commands.py
@@ -210,16 +210,29 @@ class ReftestRunner(MozbuildObject):
         #Remove the stdout handler from the internal logger and let mach deal with it
         runreftest.log.removeHandler(runreftest.log.handlers[0])
         self.log_manager.enable_unstructured()
         rv = runreftest.run(**kwargs)
         self.log_manager.disable_unstructured()
 
         return rv
 
+
+def process_test_objects(kwargs):
+    """|mach test| works by providing a test_objects argument, from
+    which the test path must be extracted and converted into a normal
+    reftest tests argument."""
+
+    if "test_objects" in kwargs:
+        if kwargs["tests"] is None:
+            kwargs["tests"] = []
+        kwargs["tests"].extend(item["path"] for item in kwargs["test_objects"])
+        del kwargs["test_objects"]
+
+
 @CommandProvider
 class MachCommands(MachCommandBase):
     @Command('reftest',
              category='testing',
              description='Run reftests (layout and graphics correctness).',
              parser=reftestcommandline.DesktopArgumentsParser)
     def run_reftest(self, **kwargs):
         kwargs["suite"] = "reftest"
@@ -258,16 +271,17 @@ class MachCommands(MachCommandBase):
              description='Run IPC crashtests (Check if crashes on a page, separate process).',
              parser=reftestcommandline.DesktopArgumentsParser)
     def run_crashtest_ipc(self, **kwargs):
         kwargs["ipc"] = True
         kwargs["suite"] = "crashtest"
         return self._run_reftest(**kwargs)
 
     def _run_reftest(self, **kwargs):
+        process_test_objects(kwargs)
         reftest = self._spawn(ReftestRunner)
         return reftest.run_desktop_test(**kwargs)
 
 
 # TODO For now b2g commands will only work with the emulator,
 # they should be modified to work with all devices.
 def is_emulator(cls):
     """Emulator needs to be configured."""
@@ -302,16 +316,17 @@ class B2GCommands(MachCommandBase):
              description='Run a remote crashtest (Check if b2g crashes on a page, remote device).',
              conditions=[conditions.is_b2g, is_emulator],
              parser=reftestcommandline.B2GArgumentParser)
     def run_crashtest_remote(self, test_file, **kwargs):
         kwargs["suite"] = "crashtest"
         return self._run_reftest(**kwargs)
 
     def _run_reftest(self, **kwargs):
+        process_test_objects(kwargs)
         if self.device_name:
             if self.device_name.startswith('emulator'):
                 emulator = 'arm'
                 if 'x86' in self.device_name:
                     emulator = 'x86'
                 kwargs['emulator'] = emulator
 
         reftest = self._spawn(ReftestRunner)

--- a/testing/mach_commands.py
+++ b/testing/mach_commands.py
@@ -91,17 +91,17 @@ TEST_SUITES = {
     },
     'luciddream': {
         'mach_command': 'luciddream',
         'kwargs': {'test_paths': None},
     },
     'reftest': {
         'aliases': ('RR', 'rr', 'Rr'),
         'mach_command': 'reftest',
-        'kwargs': {'test_file': None},
+        'kwargs': {'tests': None},
     },
     'reftest-ipc': {
         'aliases': ('Ripc',),
         'mach_command': 'reftest-ipc',
         'kwargs': {'test_file': None},
     },
     'web-platform-tests': {
         'aliases': ('wpt',),
@@ -134,17 +134,20 @@ TEST_FLAVORS = {
     'chrome': {
         'mach_command': 'mochitest',
         'kwargs': {'flavor': 'chrome', 'test_paths': []},
     },
     'mochitest': {
         'mach_command': 'mochitest',
         'kwargs': {'flavor': 'mochitest', 'test_paths': []},
     },
-    'reftest': { },
+    'reftest': {
+        'mach_command': 'reftest',
+        'kwargs': {'tests': []}
+    },
     'steeplechase': { },
     'web-platform-tests': {
         'mach_command': 'web-platform-tests',
         'kwargs': {'include': []}
     },
     'webapprt-chrome': {
         'mach_command': 'mochitest',
         'kwargs': {'flavor': 'webapprt-chrome', 'test_paths': []},