CLN: Test cleanups and follow-ups

Author: gfyoung

pandas/tests/frame/test_alter_axes.py

@@ -1052,31 +1052,31 @@ def test_rename_positional_named(self):
         tm.assert_frame_equal(result, expected)
 
     def test_rename_axis_style_raises(self):
-        # https://github.com/pandas-dev/pandas/issues/12392
-        df = DataFrame({"A": [1, 2], "B": [1, 2]}, index=['0', '1'])
+        # see gh-12392
+        df = DataFrame({"A": [1, 2], "B": [1, 2]}, index=["0", "1"])
 
         # Named target and axis
-        with pytest.raises(TypeError, match=None):
+        over_spec_msg = ("Cannot specify both 'axis' and "
+                         "any of 'index' or 'columns'")
+        with pytest.raises(TypeError, match=over_spec_msg):
             df.rename(index=str.lower, axis=1)
 
-        with pytest.raises(TypeError, match=None):
-            df.rename(index=str.lower, axis='columns')
-
-        with pytest.raises(TypeError, match=None):
-            df.rename(index=str.lower, axis='columns')
+        with pytest.raises(TypeError, match=over_spec_msg):
+            df.rename(index=str.lower, axis="columns")
 
-        with pytest.raises(TypeError, match=None):
-            df.rename(columns=str.lower, axis='columns')
+        with pytest.raises(TypeError, match=over_spec_msg):
+            df.rename(columns=str.lower, axis="columns")
 
-        with pytest.raises(TypeError, match=None):
+        with pytest.raises(TypeError, match=over_spec_msg):
             df.rename(index=str.lower, axis=0)
 
         # Multiple targets and axis
-        with pytest.raises(TypeError, match=None):
-            df.rename(str.lower, str.lower, axis='columns')
+        with pytest.raises(TypeError, match=over_spec_msg):
+            df.rename(str.lower, str.lower, axis="columns")
 
         # Too many targets
-        with pytest.raises(TypeError, match=None):
+        over_spec_msg = "Cannot specify all of 'mapper', 'index', 'columns'."
+        with pytest.raises(TypeError, match=over_spec_msg):
             df.rename(str.lower, str.lower, str.lower)
 
         # Duplicates

pandas/tests/test_strings.py

@@ -2114,29 +2114,25 @@ def test_center_ljust_rjust_fillchar(self):
         # If fillchar is not a charatter, normal str raises TypeError
         # 'aaa'.ljust(5, 'XY')
         # TypeError: must be char, not str
-        msg = "fillchar must be a character, not str"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.center(5, fillchar='XY')
+        template = "fillchar must be a character, not {dtype}"
 
-        msg = "fillchar must be a character, not str"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.ljust(5, fillchar='XY')
+        with pytest.raises(TypeError, match=template.format(dtype="str")):
+            values.str.center(5, fillchar='XY')
 
-        msg = "fillchar must be a character, not str"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.rjust(5, fillchar='XY')
+        with pytest.raises(TypeError, match=template.format(dtype="str")):
+            values.str.ljust(5, fillchar='XY')
 
-        msg = "fillchar must be a character, not int"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.center(5, fillchar=1)
+        with pytest.raises(TypeError, match=template.format(dtype="str")):
+            values.str.rjust(5, fillchar='XY')
 
-        msg = "fillchar must be a character, not int"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.ljust(5, fillchar=1)
+        with pytest.raises(TypeError, match=template.format(dtype="int")):
+            values.str.center(5, fillchar=1)
 
-        msg = "fillchar must be a character, not int"
-        with pytest.raises(TypeError, match=msg):
-            result = values.str.rjust(5, fillchar=1)
+        with pytest.raises(TypeError, match=template.format(dtype="int")):
+            values.str.ljust(5, fillchar=1)
+
+        with pytest.raises(TypeError, match=template.format(dtype="int")):
+            values.str.rjust(5, fillchar=1)
 
     def test_zfill(self):
         values = Series(['1', '22', 'aaa', '333', '45678'])