Fixed issue arrow-py#701

arrow/parser.py

@@ -218,6 +218,7 @@ def parse(self, datetime_string, fmt):
         fmt_tokens, fmt_pattern_re = self._generate_pattern_re(fmt)
 
         match = fmt_pattern_re.search(datetime_string)
+
         if match is None:
             raise ParserMatchError(
                 "Failed to match '{}' when parsing '{}'".format(fmt, datetime_string)
@@ -292,12 +293,16 @@ def _generate_pattern_re(self, fmt):
         # and time string in a natural language sentence. Therefore, searching
         # for a string of the form YYYY-MM-DD in "blah 1998-09-12 blah" will
         # work properly.
-        # Reference: https://stackoverflow.com/q/14232931/3820660
-        starting_word_boundary = r"(?<![\S])"
-        ending_word_boundary = r"(?![\S])"
-        bounded_fmt_pattern = r"{}{}{}".format(
-            starting_word_boundary, final_fmt_pattern, ending_word_boundary
-        )
+        # Certain punctuation before or after the target pattern such as
+        # "1998-09-12," is permitted. For the full list of valid punctuation,
+        # see the documentation.
+
+        starting_punctuation_bound = r"(?<!\S\S)(?<!\s[^,.;:?!\"'`\[\]{}(" \
+                                     r")<>\s])(\b|^)"
+        ending_punctuation_bound = r"(?=[,.;:?!\"'`\[\]{}()<>]?(?!\S))"
+        bounded_fmt_pattern = r"{}{}{}".format(starting_punctuation_bound,
+                                               final_fmt_pattern,
+                                               ending_punctuation_bound)
 
         return tokens, re.compile(bounded_fmt_pattern, flags=re.IGNORECASE)
 

docs/index.rst

@@ -212,6 +212,7 @@ Support for a growing number of locales (see ``locales.py`` for supported langua
 
 .. code-block:: python
 
+
     >>> future = arrow.utcnow().shift(hours=1)
     >>> future.humanize(a, locale='ru')
     'через 2 час(а,ов)'
@@ -427,6 +428,17 @@ You can also escape regular expressions by enclosing them within square brackets
     >>> arrow.get("Mon Sep 08   16:41:45   2014", fmt)
     <Arrow [2014-09-08T16:41:45+00:00]>
 
+Punctuation
+~~~~~~~~~~~
+
+You're date formats can be precede and/or be preceded by one character of
+punctuation from the list: :code:`, . ; : ? ! " ' ` [ ] { } ( ) < >`
+
+.. code-block:: python
+
+    >>> arrow.get("Tomorrow (2019-10-31) is Halloween!", "YYYY-MM-DD")
+    <Arrow [2019-10-31T00:00:00+00:00]>
+
 API Guide
 ---------
 

tests/parser_tests.py

@@ -472,7 +472,10 @@ def test_parse_with_extra_words_at_start_and_end_invalid(self):
 
     def test_parse_with_extra_words_at_start_and_end_valid(self):
         # Spaces surrounding the parsable date are ok because we
-        # allow the parsing of natural language input
+        # allow the parsing of natural language input. Additionally, a single
+        # character of specific punctuation before or after the date is okay.
+        # See docs for full list of valid punctuation.
+
         self.assertEqual(
             self.parser.parse("blah 2016 blah", "YYYY"), datetime(2016, 1, 1)
         )
@@ -527,6 +530,30 @@ def test_parse_with_extra_words_at_start_and_end_valid(self):
             datetime(2016, 5, 16, 4, 5, 6, 789120),
         )
 
+        self.assertEqual(
+            self.parser.parse(
+                "Meet me at my house on the my birthday (2019-24-11)",
+                "YYYY-DD-MM"
+            ),
+            datetime(2019, 11, 24)
+        )
+
+        self.assertEqual(
+            self.parser.parse(
+                "Monday, 9. September 2019, 16:15-20:00",
+                "dddd, D. MMMM YYYY"
+            ),
+            datetime(2019, 9, 9)
+        )
+
+        self.assertEqual(
+            self.parser.parse(
+                "A date is 11.11.2011.",
+                "DD.MM.YYYY"
+            ),
+            datetime(2011, 11, 11)
+        )
+
     def test_parse_with_leading_and_trailing_whitespace(self):
         self.assertEqual(self.parser.parse("      2016", "YYYY"), datetime(2016, 1, 1))