new validate function for axis labels

Author: phobson

probscale/tests/test_validate.py

@@ -47,7 +47,6 @@ def test_fit_arguments_invalid(kwarg):
         validate.fit_argument('junk', kwarg)
 
 
-
 @pytest.mark.parametrize(('value', 'error'), [
     ('x', None), ('y', None), ('junk', ValueError)
 ])
@@ -80,3 +79,9 @@ def test_axis_type(value, expected, error):
 ])
 def test_other_options(value, expected):
     assert validate.other_options(value) == expected
+
+
+@pytest.mark.parametrize(('value', 'expected'), [(None, ''), ('test', 'test')])
+def test_axis_label(value, expected):
+    result = validate.axis_label(value)
+    assert result == expected

probscale/validate.py

@@ -18,13 +18,13 @@ def axes_object(ax):
     return fig, ax
 
 
-def axis_name(axname, argname):
+def axis_name(axis, axname):
     valid_args = ['x', 'y']
-    if axname.lower() not in valid_args:
+    if axis.lower() not in valid_args:
         msg = 'Invalid value for {} ({}). Must be on of {}.'
-        raise ValueError(msg.format(argname, axname, valid_args))
+        raise ValueError(msg.format(axname, axis, valid_args))
 
-    return axname.lower()
+    return axis.lower()
 
 
 def fit_argument(arg, argname):
@@ -42,5 +42,12 @@ def axis_type(axtype):
     return axtype.lower()
 
 
+def axis_label(label):
+    if label is None:
+        return ''
+    else:
+        return label
+
+
 def other_options(options):
     return dict() if options is None else options.copy()