Update probe tests

Author: michaeljoseph

tests/test_probe.py

@@ -1,14 +1,18 @@
-from pytest import raises
-import shutil
-
 from changes import probe
 from . import context, setup, teardown
 
 
 def test_probe_project():
     assert probe.probe_project(context)
 
-def test_probe_with_alt_requirements():
-    with raises(Exception):
-        shutil.rmtree(context.requirements)
-        probe.probe_project(context)
+
+def test_has_binary():
+    assert probe.has_binary('git')
+
+
+def test_has_no_binary():
+    assert not probe.has_binary('foo')
+
+
+def test_has_test_runner():
+    assert probe.has_test_runner()