--- a/js/moz.build
+++ b/js/moz.build
@@ -8,12 +8,12 @@ with Files("**"):
 for header in ('GCAnnotations.h', 'GCAPI.h', 'HeapAPI.h', 'RootingAPI.h', 'SliceBudget.h', 'SweepingAPI.h', 'TraceKind.h', 'TracingAPI.h', 'WeakMapPtr.h', 'GCHashTable.h', 'GCPolicyAPI.h', 'GCVariant.h', 'GCVector.h'):
     with Files('public/' + header):
         BUG_COMPONENT = component_gc
 
 with Files('public/TrackedOptimizationInfo.h'):
     BUG_COMPONENT = component_jit
 
 with Files("src/**"):
-    SCHEDULES.inclusive += ['jittest']
+    SCHEDULES.inclusive += ['jittest', 'jsreftest']
 
 with Files("public/**"):
-    SCHEDULES.inclusive += ['jittest']
+    SCHEDULES.inclusive += ['jittest', 'jsreftest']

--- a/python/mozbuild/mozbuild/schedules.py
+++ b/python/mozbuild/mozbuild/schedules.py
@@ -10,18 +10,20 @@ skip-unless-schedules optimizations in t
 from __future__ import absolute_import, unicode_literals, print_function
 
 # TODO: ideally these lists could be specified in moz.build itself
 
 INCLUSIVE_COMPONENTS = [
     'py-lint',
     'js-lint',
     'yaml-lint',
-    # tests that only run when certain files have changed
+    # test suites that only run when certain files have changed
     'jittest',
+    # test flavors
+    'jsreftest',
 ]
 INCLUSIVE_COMPONENTS = sorted(INCLUSIVE_COMPONENTS)
 
 EXCLUSIVE_COMPONENTS = [
     # os families
     'android',
     'linux',
     'macosx',

--- a/taskcluster/ci/test/tests.yml
+++ b/taskcluster/ci/test/tests.yml
@@ -343,19 +343,17 @@ jsreftest:
                         macosx.*:
                             - unittests/mac_unittest.py
                         linux.*:
                             - unittests/linux_unittest.py
                             - remove_executables.py
                 extra-options:
                     - --reftest-suite=jsreftest
     when:
-        files-changed:
-            - js/src/**
-            - js/public/**
+        schedules: ['jsreftest']
     tier:
         by-test-platform:
             linux64-qr/.*: 1
             windows10-64-asan.*: 3
             default: default
 
 marionette:
     description: "Marionette unittest run"

--- a/taskcluster/taskgraph/transforms/tests.py
+++ b/taskcluster/taskgraph/transforms/tests.py
@@ -362,16 +362,19 @@ test_description_schema = Schema({
     'test-name': basestring,
 
     # the product name, defaults to firefox
     Optional('product'): basestring,
 
     # conditional files to determine when these tests should be run
     Optional('when'): Any({
         Optional('files-changed'): [basestring],
+
+        # SCHEDULES components; the test suite and platform family will be added automatically.
+        Optional('schedules'): [basestring],
     }),
 
     Optional('worker-type'): optionally_keyed_by(
         'test-platform',
         Any(basestring, None),
     ),
 
 }, required=True)
@@ -931,20 +934,23 @@ def make_job_description(config, tests):
         }
         jobdesc['treeherder'] = {
             'symbol': test['treeherder-symbol'],
             'kind': 'test',
             'tier': test['tier'],
             'platform': test.get('treeherder-machine-platform', test['build-platform']),
         }
 
-        if test.get('when'):
-            jobdesc['when'] = test['when']
+        when = test.get('when')
+        if when and 'files-changed' in when:
+            jobdesc['when'] = when
         else:
             schedules = [suite, platform_family(test['build-platform'])]
+            if when and 'schedules' in when:
+                schedules.extend(when['schedules'])
             if config.params['project'] != 'try':
                 # for non-try branches, include SETA
                 jobdesc['optimization'] = {'skip-unless-schedules-or-seta': schedules}
             else:
                 # otherwise just use skip-unless-schedules
                 jobdesc['optimization'] = {'skip-unless-schedules': schedules}
 
         run = jobdesc['run'] = {}