8th day of python challenges 111-117

venv/lib/python3.6/site-packages/pandas/tests/tslibs/test_parsing.py

@@ -0,0 +1,211 @@
+"""
+Tests for Timestamp parsing, aimed at pandas/_libs/tslibs/parsing.pyx
+"""
+from datetime import datetime
+
+from dateutil.parser import parse
+import numpy as np
+import pytest
+
+from pandas._libs.tslibs import parsing
+from pandas._libs.tslibs.parsing import parse_time_string
+import pandas.util._test_decorators as td
+
+from pandas.util import testing as tm
+
+
+def test_parse_time_string():
+    (date, parsed, reso) = parse_time_string("4Q1984")
+    (date_lower, parsed_lower, reso_lower) = parse_time_string("4q1984")
+
+    assert date == date_lower
+    assert reso == reso_lower
+    assert parsed == parsed_lower
+
+
+@pytest.mark.parametrize(
+    "dashed,normal", [("1988-Q2", "1988Q2"), ("2Q-1988", "2Q1988")]
+)
+def test_parse_time_quarter_with_dash(dashed, normal):
+    # see gh-9688
+    (date_dash, parsed_dash, reso_dash) = parse_time_string(dashed)
+    (date, parsed, reso) = parse_time_string(normal)
+
+    assert date_dash == date
+    assert parsed_dash == parsed
+    assert reso_dash == reso
+
+
+@pytest.mark.parametrize("dashed", ["-2Q1992", "2-Q1992", "4-4Q1992"])
+def test_parse_time_quarter_with_dash_error(dashed):
+    msg = "Unknown datetime string format, unable to parse: {dashed}"
+
+    with pytest.raises(parsing.DateParseError, match=msg.format(dashed=dashed)):
+        parse_time_string(dashed)
+
+
+@pytest.mark.parametrize(
+    "date_string,expected",
+    [
+        ("123.1234", False),
+        ("-50000", False),
+        ("999", False),
+        ("m", False),
+        ("T", False),
+        ("Mon Sep 16, 2013", True),
+        ("2012-01-01", True),
+        ("01/01/2012", True),
+        ("01012012", True),
+        ("0101", True),
+        ("1-1", True),
+    ],
+)
+def test_does_not_convert_mixed_integer(date_string, expected):
+    assert parsing._does_string_look_like_datetime(date_string) is expected
+
+
+@pytest.mark.parametrize(
+    "date_str,kwargs,msg",
+    [
+        (
+            "2013Q5",
+            dict(),
+            (
+                "Incorrect quarterly string is given, "
+                "quarter must be between 1 and 4: 2013Q5"
+            ),
+        ),
+        # see gh-5418
+        (
+            "2013Q1",
+            dict(freq="INVLD-L-DEC-SAT"),
+            (
+                "Unable to retrieve month information "
+                "from given freq: INVLD-L-DEC-SAT"
+            ),
+        ),
+    ],
+)
+def test_parsers_quarterly_with_freq_error(date_str, kwargs, msg):
+    with pytest.raises(parsing.DateParseError, match=msg):
+        parsing.parse_time_string(date_str, **kwargs)
+
+
+@pytest.mark.parametrize(
+    "date_str,freq,expected",
+    [
+        ("2013Q2", None, datetime(2013, 4, 1)),
+        ("2013Q2", "A-APR", datetime(2012, 8, 1)),
+        ("2013-Q2", "A-DEC", datetime(2013, 4, 1)),
+    ],
+)
+def test_parsers_quarterly_with_freq(date_str, freq, expected):
+    result, _, _ = parsing.parse_time_string(date_str, freq=freq)
+    assert result == expected
+
+
+@pytest.mark.parametrize(
+    "date_str", ["2Q 2005", "2Q-200A", "2Q-200", "22Q2005", "2Q200.", "6Q-20"]
+)
+def test_parsers_quarter_invalid(date_str):
+    if date_str == "6Q-20":
+        msg = (
+            "Incorrect quarterly string is given, quarter "
+            "must be between 1 and 4: {date_str}"
+        )
+    else:
+        msg = "Unknown datetime string format, unable to parse: {date_str}"
+
+    with pytest.raises(ValueError, match=msg.format(date_str=date_str)):
+        parsing.parse_time_string(date_str)
+
+
+@pytest.mark.parametrize(
+    "date_str,expected",
+    [("201101", datetime(2011, 1, 1, 0, 0)), ("200005", datetime(2000, 5, 1, 0, 0))],
+)
+def test_parsers_month_freq(date_str, expected):
+    result, _, _ = parsing.parse_time_string(date_str, freq="M")
+    assert result == expected
+
+
+@td.skip_if_not_us_locale
+@pytest.mark.parametrize(
+    "string,fmt",
+    [
+        ("20111230", "%Y%m%d"),
+        ("2011-12-30", "%Y-%m-%d"),
+        ("30-12-2011", "%d-%m-%Y"),
+        ("2011-12-30 00:00:00", "%Y-%m-%d %H:%M:%S"),
+        ("2011-12-30T00:00:00", "%Y-%m-%dT%H:%M:%S"),
+        ("2011-12-30 00:00:00.000000", "%Y-%m-%d %H:%M:%S.%f"),
+    ],
+)
+def test_guess_datetime_format_with_parseable_formats(string, fmt):
+    result = parsing._guess_datetime_format(string)
+    assert result == fmt
+
+
+@pytest.mark.parametrize("dayfirst,expected", [(True, "%d/%m/%Y"), (False, "%m/%d/%Y")])
+def test_guess_datetime_format_with_dayfirst(dayfirst, expected):
+    ambiguous_string = "01/01/2011"
+    result = parsing._guess_datetime_format(ambiguous_string, dayfirst=dayfirst)
+    assert result == expected
+
+
+@td.skip_if_has_locale
+@pytest.mark.parametrize(
+    "string,fmt",
+    [
+        ("30/Dec/2011", "%d/%b/%Y"),
+        ("30/December/2011", "%d/%B/%Y"),
+        ("30/Dec/2011 00:00:00", "%d/%b/%Y %H:%M:%S"),
+    ],
+)
+def test_guess_datetime_format_with_locale_specific_formats(string, fmt):
+    result = parsing._guess_datetime_format(string)
+    assert result == fmt
+
+
+@pytest.mark.parametrize(
+    "invalid_dt",
+    [
+        "2013",
+        "01/2013",
+        "12:00:00",
+        "1/1/1/1",
+        "this_is_not_a_datetime",
+        "51a",
+        9,
+        datetime(2011, 1, 1),
+    ],
+)
+def test_guess_datetime_format_invalid_inputs(invalid_dt):
+    # A datetime string must include a year, month and a day for it to be
+    # guessable, in addition to being a string that looks like a datetime.
+    assert parsing._guess_datetime_format(invalid_dt) is None
+
+
+@pytest.mark.parametrize(
+    "string,fmt",
+    [
+        ("2011-1-1", "%Y-%m-%d"),
+        ("1/1/2011", "%m/%d/%Y"),
+        ("30-1-2011", "%d-%m-%Y"),
+        ("2011-1-1 0:0:0", "%Y-%m-%d %H:%M:%S"),
+        ("2011-1-3T00:00:0", "%Y-%m-%dT%H:%M:%S"),
+        ("2011-1-1 00:00:00", "%Y-%m-%d %H:%M:%S"),
+    ],
+)
+def test_guess_datetime_format_no_padding(string, fmt):
+    # see gh-11142
+    result = parsing._guess_datetime_format(string)
+    assert result == fmt
+
+
+def test_try_parse_dates():
+    arr = np.array(["5/1/2000", "6/1/2000", "7/1/2000"], dtype=object)
+    result = parsing.try_parse_dates(arr, dayfirst=True)
+
+    expected = np.array([parse(d, dayfirst=True) for d in arr])
+    tm.assert_numpy_array_equal(result, expected)