TST: test the plot arg replacer directly

jankatins · jankatins · commit 0f781a16c2aa · 2015-08-31T12:06:41.000+02:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -68,6 +68,7 @@ def _plot_args_replacer(args, data):
                 warnings.warn(msg, RuntimeWarning, stacklevel=3)
             _replacer += ["x", "y", "c"]
 
+        # if less than 3, the above code handled it so just return
         if len(remaining) <= 3:
             return _replacer
 
diff --git a/lib/matplotlib/tests/test_labeled_data_unpacking.py b/lib/matplotlib/tests/test_labeled_data_unpacking.py
@@ -459,50 +459,34 @@ def funcy(ax, x, y, z, bar=None):
 
 
 def test_positional_parameter_names_as_function():
-    #
-    # this is a replace for plot, which can take args as
-    # x,y,c,x,y,c or x,y,x,y,c,x,y
-    def replacer(args, data):
-        _replacer = []
-        remaining = args
-        while 1:
-            if len(remaining) == 1:
-                import warnings
-
-                msg = "Missing argument: color spec ('c=..') is in data?"
-                warnings.warn(msg, RuntimeWarning, stacklevel=3)
-                _replacer += ["x"]
-            elif len(remaining) == 2:
-                _replacer += ["x", "y"]
-            elif len(remaining) == 3:
-                if remaining[2] in data:
-                    import warnings
-
-                    msg = "Found a color spec ('c') in data."
-                    warnings.warn(msg, RuntimeWarning, stacklevel=3)
-                _replacer += ["x", "y", "c"]
-
-            if len(remaining) <= 3:
-                return _replacer
-
-            # More than 3 -> split off the beginning and continue
-            if remaining[2] not in data:
-                _replacer += ["x", "y", "c"]
-                isplit = 3
-            else:
-                _replacer += ["x", "y"]
-                isplit = 2
-            remaining = remaining[isplit:]
+    # Also test the _plot_arg_replacer for plot...
+    from matplotlib.axes._axes import _plot_args_replacer
 
+    # this is a replace for plot, which can take args as
+    # x,y,c,x,y,c or x,y,x,y,c,x,y or any other way... :-/
     @unpack_labeled_data(replace_names=["x", "y"],
-                         positional_parameter_names=replacer)
+                         positional_parameter_names=_plot_args_replacer)
     def funcy(ax, *args, **kwargs):
         return "{args} | {kwargs}".format(args=args, kwargs=kwargs)
 
     data = {"x": "X", "y": "Y"}
+    assert_equal(funcy(None, "x", "y", data=data),
+                 "('X', 'Y') | {}")
+    assert_equal(funcy(None, "x", "y", "c", data=data),
+                 "('X', 'Y', 'c') | {}")
     assert_equal(funcy(None, "x", "y", "c", "x", "y", "x", "y", data=data),
                  "('X', 'Y', 'c', 'X', 'Y', 'X', 'Y') | {}")
+
+    # the color spec should not be in data...
     data = {"x": "X", "y": "Y", "c": "!!"}
     with assert_produces_warning(RuntimeWarning):
         assert_equal(funcy(None, "x", "y", "c", "x", "y", "x", "y", data=data),
                      "('X', 'Y', '!!', 'X', 'Y', 'X', 'y') | {}")
+
+    # And this is the case which we screw up, as we can't distinguish
+    # between a color spec and data...
+    # -> This test should actually produce a warning, if someone finds a way
+    # to distinguish between data and color spec...
+    with assert_produces_warning(False):
+        assert_equal(funcy(None, "x", "y", "c", "x", "y", "c", data=data),
+                     "('X', 'Y', '!!', 'X', 'Y', '!!') | {}")
