BUG FIX: Using Series.str.fullmatch() and Series.str.match() with a compiled regex fails with arrow strings

[khemkaran10]

Fixes: #61952
After Fix:

DATA = ["applep", "bananap", "Cherryp", "DATEp", "eGGpLANTp", "123p", "23.45p"]
s=pd.Series(DATA)
s.str.fullmatch(re.compile(r"applep"))

Output:
0     True
1    False
2    False
3    False
4    False
5    False
6    False
dtype: bool

DATA = ["applep", "bananap", "Cherryp", "DATEp", "eGGpLANTp", "123p", "23.45p"]
sa=pd.Series(DATA, dtype="string[pyarrow]")
sa.str.match(re.compile(r"applep"))

Output:
0     True
1    False
2    False
3    False
4    False
5    False
6    False
dtype: boolean

• closes BUG: Using Series.str.fullmatch() and Series.str.match() with a compiled regex fails with arrow strings #61952
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.

[jorisvandenbossche]

Thanks!

It seems we don't actually document that we support a compiled regular expression, although it works in practice because we pass pat to re.compile() in the non-arrow version, and that works.
But so it would be good to update the documentation and typing then to reflect the fact that a compiled pattern is also supported.

[khemkaran10]

@jorisvandenbossche Moved tests to pandas/tests/strings/test_find_replace.py and made a minor change to the docstring. I’m not sure what changes need to be made in docs. could you please provide more details?