add issue number and try except

pandas/_libs/tslibs/strptime.pyx

@@ -292,7 +292,7 @@ def array_strptime(ndarray[object] values, object fmt,
                             break
             elif parse_code == 19:
                 z = found_dict['z']
-                gmtoff, gmtoff_fraction = _parse_timezone_directive(z)
+                gmtoff, gmtoff_fraction = parse_timezone_directive(z)
 
         # If we know the wk of the year and what day of that wk, we can figure
         # out the Julian day of the year.
@@ -656,7 +656,7 @@ cdef _calc_julian_from_U_or_W(int year, int week_of_year,
         days_to_week = week_0_length + (7 * (week_of_year - 1))
         return 1 + days_to_week + day_of_week
 
-cdef _parse_timezone_directive(object z):
+cdef parse_timezone_directive(object z):
     """
     Parse the '%z' directive and return an offset from UTC
 
@@ -674,22 +674,23 @@ cdef _parse_timezone_directive(object z):
         object gmtoff_remainder, gmtoff_remainder_padding
 
     if z == 'Z':
-        gmtoff = 0
-        gmtoff_fraction = 0
+        return (0, 0)
     else:
-        if z[3] == ':':
-            z = z[:3] + z[4:]
-            if len(z) > 5:
-                if z[5] != ':':
-                    msg = "Inconsistent use of : in {0}"
-                    raise ValueError(msg.format(z))
-                z = z[:5] + z[6:]
-        hours = int(z[1:3])
-        minutes = int(z[3:5])
-        seconds = int(z[5:7] or 0)
-        gmtoff = (hours * 60 * 60) + (minutes * 60) + seconds
-        gmtoff_remainder = z[8:]
-
+        try:
+            if z[3] == ':':
+                z = z[:3] + z[4:]
+                if len(z) > 5:
+                    if z[5] != ':':
+                        msg = "Inconsistent use of : in {0}"
+                        raise ValueError(msg.format(z))
+                    z = z[:5] + z[6:]
+            hours = int(z[1:3])
+            minutes = int(z[3:5])
+            seconds = int(z[5:7] or 0)
+            gmtoff = (hours * 60 * 60) + (minutes * 60) + seconds
+            gmtoff_remainder = z[8:]
+        except ValueError:
+            raise ValueError("Could not parse offset: {0}".format(z))
         # Pad to always return microseconds.
         pad_number = 6 - len(gmtoff_remainder)
         gmtoff_remainder_padding = "0" * pad_number
@@ -698,5 +699,4 @@ cdef _parse_timezone_directive(object z):
         if z.startswith("-"):
             gmtoff = -gmtoff
             gmtoff_fraction = -gmtoff_fraction
-
-    return (gmtoff, gmtoff_fraction)
+        return (gmtoff, gmtoff_fraction)

pandas/tests/indexes/datetimes/test_tools.py

@@ -213,6 +213,7 @@ def test_to_datetime_format_weeks(self, cache):
     def test_to_datetime_parse_tzname_or_tzoffset(self, box, const,
                                                   assert_equal, fmt,
                                                   dates, expected_dates):
+        # GH 13486
         # %z or %Z parsing
         result = pd.to_datetime(dates, format=fmt, box=box)
         expected = const(expected_dates)
@@ -238,6 +239,7 @@ def test_to_datetime_parse_tzname_or_tzoffset(self, box, const,
     def test_to_datetime_parse_tzname_and_tzoffset(self, box, const,
                                                    assert_equal, dates,
                                                    expected_dates):
+        # GH 13486
         # %z and %Z parsing
         fmt = '%Y-%m-%d %H:%M:%S %Z %z'
         result = pd.to_datetime(dates, format=fmt, box=box)