TST: Parameterize test_strings.py (pandas-dev#44875)

Author: mroeschke

pandas/tests/strings/test_strings.py

@@ -137,15 +137,11 @@ def test_repeat_mixed_object():
     tm.assert_series_equal(result, expected)
 
 
-def test_repeat_with_null(any_string_dtype):
+@pytest.mark.parametrize("arg, repeat", [[None, 4], ["b", None]])
+def test_repeat_with_null(any_string_dtype, arg, repeat):
     # GH: 31632
-    ser = Series(["a", None], dtype=any_string_dtype)
-    result = ser.str.repeat([3, 4])
-    expected = Series(["aaa", np.nan], dtype=any_string_dtype)
-    tm.assert_series_equal(result, expected)
-
-    ser = Series(["a", "b"], dtype=any_string_dtype)
-    result = ser.str.repeat([3, None])
+    ser = Series(["a", arg], dtype=any_string_dtype)
+    result = ser.str.repeat([3, repeat])
     expected = Series(["aaa", np.nan], dtype=any_string_dtype)
     tm.assert_series_equal(result, expected)
 
@@ -397,27 +393,28 @@ def test_index_not_found_raises(index_or_series, any_string_dtype):
         obj.str.index("DE")
 
 
-def test_index_wrong_type_raises(index_or_series, any_string_dtype):
+@pytest.mark.parametrize("method", ["index", "rindex"])
+def test_index_wrong_type_raises(index_or_series, any_string_dtype, method):
     obj = index_or_series([], dtype=any_string_dtype)
     msg = "expected a string object, not int"
 
     with pytest.raises(TypeError, match=msg):
-        obj.str.index(0)
-
-    with pytest.raises(TypeError, match=msg):
-        obj.str.rindex(0)
+        getattr(obj.str, method)(0)
 
 
-def test_index_missing(any_string_dtype):
+@pytest.mark.parametrize(
+    "method, exp",
+    [
+        ["index", [1, 1, 0]],
+        ["rindex", [3, 1, 2]],
+    ],
+)
+def test_index_missing(any_string_dtype, method, exp):
     ser = Series(["abcb", "ab", "bcbe", np.nan], dtype=any_string_dtype)
     expected_dtype = np.float64 if any_string_dtype == "object" else "Int64"
 
-    result = ser.str.index("b")
-    expected = Series([1, 1, 0, np.nan], dtype=expected_dtype)
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.rindex("b")
-    expected = Series([3, 1, 2, np.nan], dtype=expected_dtype)
+    result = getattr(ser.str, method)("b")
+    expected = Series(exp + [np.nan], dtype=expected_dtype)
     tm.assert_series_equal(result, expected)
 
 
@@ -488,53 +485,51 @@ def test_slice_replace(start, stop, repl, expected, any_string_dtype):
     tm.assert_series_equal(result, expected)
 
 
-def test_strip_lstrip_rstrip(any_string_dtype):
+@pytest.mark.parametrize(
+    "method, exp",
+    [
+        ["strip", ["aa", "bb", np.nan, "cc"]],
+        ["lstrip", ["aa   ", "bb \n", np.nan, "cc  "]],
+        ["rstrip", ["  aa", " bb", np.nan, "cc"]],
+    ],
+)
+def test_strip_lstrip_rstrip(any_string_dtype, method, exp):
     ser = Series(["  aa   ", " bb \n", np.nan, "cc  "], dtype=any_string_dtype)
 
-    result = ser.str.strip()
-    expected = Series(["aa", "bb", np.nan, "cc"], dtype=any_string_dtype)
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.lstrip()
-    expected = Series(["aa   ", "bb \n", np.nan, "cc  "], dtype=any_string_dtype)
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.rstrip()
-    expected = Series(["  aa", " bb", np.nan, "cc"], dtype=any_string_dtype)
+    result = getattr(ser.str, method)()
+    expected = Series(exp, dtype=any_string_dtype)
     tm.assert_series_equal(result, expected)
 
 
-def test_strip_lstrip_rstrip_mixed_object():
+@pytest.mark.parametrize(
+    "method, exp",
+    [
+        ["strip", ["aa", np.nan, "bb"]],
+        ["lstrip", ["aa  ", np.nan, "bb \t\n"]],
+        ["rstrip", ["  aa", np.nan, " bb"]],
+    ],
+)
+def test_strip_lstrip_rstrip_mixed_object(method, exp):
     ser = Series(["  aa  ", np.nan, " bb \t\n", True, datetime.today(), None, 1, 2.0])
 
-    result = ser.str.strip()
-    expected = Series(["aa", np.nan, "bb", np.nan, np.nan, np.nan, np.nan, np.nan])
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.lstrip()
-    expected = Series(
-        ["aa  ", np.nan, "bb \t\n", np.nan, np.nan, np.nan, np.nan, np.nan]
-    )
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.rstrip()
-    expected = Series(["  aa", np.nan, " bb", np.nan, np.nan, np.nan, np.nan, np.nan])
+    result = getattr(ser.str, method)()
+    expected = Series(exp + [np.nan, np.nan, np.nan, np.nan, np.nan])
     tm.assert_series_equal(result, expected)
 
 
-def test_strip_lstrip_rstrip_args(any_string_dtype):
+@pytest.mark.parametrize(
+    "method, exp",
+    [
+        ["strip", ["ABC", " BNSD", "LDFJH "]],
+        ["lstrip", ["ABCxx", " BNSD", "LDFJH xx"]],
+        ["rstrip", ["xxABC", "xx BNSD", "LDFJH "]],
+    ],
+)
+def test_strip_lstrip_rstrip_args(any_string_dtype, method, exp):
     ser = Series(["xxABCxx", "xx BNSD", "LDFJH xx"], dtype=any_string_dtype)
 
-    result = ser.str.strip("x")
-    expected = Series(["ABC", " BNSD", "LDFJH "], dtype=any_string_dtype)
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.lstrip("x")
-    expected = Series(["ABCxx", " BNSD", "LDFJH xx"], dtype=any_string_dtype)
-    tm.assert_series_equal(result, expected)
-
-    result = ser.str.rstrip("x")
-    expected = Series(["xxABC", "xx BNSD", "LDFJH "], dtype=any_string_dtype)
+    result = getattr(ser.str, method)("x")
+    expected = Series(exp, dtype=any_string_dtype)
     tm.assert_series_equal(result, expected)