--- a/taskcluster/ci/source-test/python.yml
+++ b/taskcluster/ci/source-test/python.yml
@@ -152,8 +152,18 @@ reftest-harness:
             ./mach python-test --subsuite reftest
     when:
         files-changed:
             - 'layout/tools/reftest/**'
             - 'testing/mozbase/moztest/moztest/selftest/**'
             - 'testing/mozharness/mozharness/base/log.py'
             - 'testing/mozharness/mozharness/mozilla/structuredlog.py'
             - 'testing/mozharness/mozharness/mozilla/testing/errors.py'
+
+tryselect:
+    description: tools/tryselect unit tests
+    treeherder:
+        symbol: py(try)
+    run:
+        mach: python-test --subsuite try
+    when:
+        files-changed:
+            - 'tools/tryselect/**'

--- a/tools/moz.build
+++ b/tools/moz.build
@@ -48,8 +48,12 @@ with Files("update-packaging/**"):
 
 SPHINX_TREES['lint'] = 'lint/docs'
 SPHINX_TREES['compare-locales'] = 'compare-locales/docs'
 SPHINX_TREES['try'] = 'tryselect/docs'
 
 CRAMTEST_MANIFESTS += [
     'tryselect/test/cram.ini',
 ]
+
+PYTHON_UNITTEST_MANIFESTS += [
+    'tryselect/test/python.ini',
+]

new file mode 100644
--- /dev/null
+++ b/tools/tryselect/test/conftest.py
@@ -0,0 +1,17 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+
+def pytest_generate_tests(metafunc):
+    if all(fixture in metafunc.fixturenames for fixture in ('template', 'args', 'expected')):
+        def load_tests():
+            for template, tests in metafunc.module.TEMPLATE_TESTS.items():
+                for args, expected in tests:
+                    yield (template, args, expected)
+
+        tests = list(load_tests())
+        ids = ['{} {}'.format(t[0], ' '.join(t[1])).strip() for t in tests]
+        metafunc.parametrize('template,args,expected', tests, ids=ids)

new file mode 100644
--- /dev/null
+++ b/tools/tryselect/test/python.ini
@@ -0,0 +1,4 @@
+[DEFAULT]
+subsuite=try
+
+[test_templates.py]

new file mode 100644
--- /dev/null
+++ b/tools/tryselect/test/test_templates.py
@@ -0,0 +1,51 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import inspect
+from argparse import ArgumentParser
+
+import mozunit
+import pytest
+
+from tryselect.templates import all_templates
+
+
+# templates have a list of tests of the form (input, expected)
+TEMPLATE_TESTS = {
+    'artifact': [
+        (['--no-artifact'], None),
+        (['--artifact'], {'enabled': '1'}),
+    ],
+    'env': [
+        ([], None),
+        (['--env', 'foo=bar', '--env', 'num=10'], {'foo': 'bar', 'num': '10'}),
+    ],
+    'rebuild': [
+        ([], None),
+        (['--rebuild', '10'], 10),
+        (['--rebuild', '1'], SystemExit),
+        (['--rebuild', '21'], SystemExit),
+    ],
+}
+
+
+def test_templates(template, args, expected):
+    parser = ArgumentParser()
+
+    t = all_templates[template]()
+    t.add_arguments(parser)
+
+    if inspect.isclass(expected) and issubclass(expected, BaseException):
+        with pytest.raises(expected):
+            args = parser.parse_args(args)
+            t.context(**vars(args))
+    else:
+        args = parser.parse_args(args)
+        assert t.context(**vars(args)) == expected
+
+
+if __name__ == '__main__':
+    mozunit.main()