diff --git a/t/pytest.do b/t/pytest.do
new file mode 100644
index 0000000..7680156
--- /dev/null
+++ b/t/pytest.do
@@ -0,0 +1,2 @@
+exec >&2
+python tstate.py
diff --git a/t/test.do b/t/test.do
index f6821e7..4b019f3 100644
--- a/t/test.do
+++ b/t/test.do
@@ -4,4 +4,4 @@ redo nonshelltest shelltest \
 	deltest deltest2 test.args test2.args passfailtest chdirtest \
 	curse/test deps/test "space dir/test" modetest makedir2 \
 	silencetest touchtest stamp/test alwaystest ifcreate-test \
-	unicode blank/blank vartest atime autosubdir/test
\ No newline at end of file
+	unicode blank/blank vartest atime autosubdir/test pytest
diff --git a/t/tstate.py b/t/tstate.py
new file mode 100644
index 0000000..c9762d2
--- /dev/null
+++ b/t/tstate.py
@@ -0,0 +1,9 @@
+import sys
+sys.path.insert(0, '..')
+import state
+
+assert(state.relpath('/a/b/c', '/a/b') == 'c')
+assert(state.relpath('/a/b/c/', '/a/b') == 'c')
+assert(state.relpath('/a/b/c', '/a/b/') == 'c')
+assert(state.relpath('/a/b/c//', '/a/b/') == 'c')
+assert(state.relpath('/a/b/c/../d', '/a/b/') == 'd')