small change for flask8 compliance. Adds entry to next_api_changes/behaviour.rst

rscmendes · rscmendes · commit a9ebd40c774d · 2019-12-15T14:30:07.000Z
diff --git a/doc/api/next_api_changes/behaviour.rst b/doc/api/next_api_changes/behaviour.rst
@@ -41,3 +41,12 @@ did nothing, when passed an unsupported value. It now raises a ``ValueError``.
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ``backend_pgf.LatexManager.latex`` is now created with ``encoding="utf-8"``, so
 its ``stdin``, ``stdout``, and ``stderr`` attributes are utf8-encoded.
+
+``pyplot.xticks()`` and ``pyplot.yticks()``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Previously, passing labels without passing the ticks to either `.pyplot.xticks`
+and `.pyplot.yticks` would result in
+
+    TypeError: object of type 'NoneType' has no len()
+
+It now raises a ``ValueError`` with a proper description of the error.
diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
@@ -1397,8 +1397,8 @@ def xticks(ticks=None, labels=None, **kwargs):
     if ticks is None:
         locs = ax.get_xticks()
         if labels is not None:
-            raise TypeError("xticks(): Parameter 'labels' can't be set without "
-                            "setting 'ticks'")
+            raise TypeError("xticks(): Parameter 'labels' can't be set "
+                            "without setting 'ticks'")
     else:
         locs = ax.set_xticks(ticks)
 
@@ -1457,8 +1457,8 @@ def yticks(ticks=None, labels=None, **kwargs):
     if ticks is None:
         locs = ax.get_yticks()
         if labels is not None:
-            raise TypeError("yticks(): Parameter 'labels' can't be set without "
-                            "setting 'ticks'")
+            raise TypeError("yticks(): Parameter 'labels' can't be set "
+                            "without setting 'ticks'")
     else:
         locs = ax.set_yticks(ticks)
 
