Fix a bug where location() wouldn't do anything when passed 0s.

2 files changed, 13 insertions, 3 deletions

diff --git a/blessings/__init__.py b/blessings/__init__.py
index dbd4b69..6f8c107 100644
--- a/blessings/__init__.py
+++ b/blessings/__init__.py
@@ -448,11 +448,11 @@ class Location(object):
     def __enter__(self):
         """Save position and move to the requested column, row, or both."""
         self.term.stream.write(self.term.save)  # save position
-        if self.x and self.y:
+        if self.x is not None and self.y is not None:
             self.term.stream.write(self.term.move(self.y, self.x))
-        elif self.x:
+        elif self.x is not None:
             self.term.stream.write(self.term.move_x(self.x))
-        elif self.y:
+        elif self.y is not None:
             self.term.stream.write(self.term.move_y(self.y))
 
     def __exit__(self, type, value, tb):
diff --git a/blessings/tests.py b/blessings/tests.py
index 72236ae..817e766 100644
--- a/blessings/tests.py
+++ b/blessings/tests.py
@@ -111,6 +111,16 @@ def test_null_location():
                              unicode_cap('rc'))
 
 
+def test_zero_location():
+    """Make sure ``location()`` pays attention to 0-valued args."""
+    t = TestTerminal(stream=StringIO(), force_styling=True)
+    with t.location(0, 0):
+        pass
+    eq_(t.stream.getvalue(), unicode_cap('sc') +
+                             unicode_parm('cup', 0, 0) +
+                             unicode_cap('rc'))
+
+
 def test_null_fileno():
     """Make sure ``Terminal`` works when ``fileno`` is ``None``.