move libfreqs and liboffsets tests to test_tslibs, move parsing tests, with to_datetime test moved to test_tools (pandas-dev#19638)

Author: jbrockmendel

pandas/tests/indexes/datetimes/test_tools.py

@@ -187,6 +187,18 @@ def test_to_datetime_format_weeks(self, cache):
 
 
 class TestToDatetime(object):
+    def test_to_datetime_pydatetime(self):
+        actual = pd.to_datetime(datetime(2008, 1, 15))
+        assert actual == datetime(2008, 1, 15)
+
+    def test_to_datetime_YYYYMMDD(self):
+        actual = pd.to_datetime('20080115')
+        assert actual == datetime(2008, 1, 15)
+
+    def test_to_datetime_unparseable_ignore(self):
+        # unparseable
+        s = 'Month 1, 1999'
+        assert pd.to_datetime(s, errors='ignore') == s
 
     @td.skip_if_windows  # `tm.set_timezone` does not work in windows
     def test_to_datetime_now(self):

pandas/tests/tseries/test_libfrequencies.py renamed to pandas/tests/tslibs/test_libfrequencies.py

@@ -7,7 +7,6 @@
 import pytest
 from dateutil.parser import parse
 
-import pandas as pd
 import pandas.util._test_decorators as td
 from pandas.conftest import is_dateutil_le_261, is_dateutil_gt_261
 from pandas import compat
@@ -16,18 +15,6 @@
 from pandas._libs.tslibs.parsing import parse_time_string
 
 
-def test_to_datetime1():
-    actual = pd.to_datetime(datetime(2008, 1, 15))
-    assert actual == datetime(2008, 1, 15)
-
-    actual = pd.to_datetime('20080115')
-    assert actual == datetime(2008, 1, 15)
-
-    # unparseable
-    s = 'Month 1, 1999'
-    assert pd.to_datetime(s, errors='ignore') == s
-
-
 class TestParseQuarters(object):
 
     def test_parse_time_string(self):