Re: [PATCH 10/28] qapi: Rework name checking in preparation of stricter checking

[Markus Armbruster]

Markus Armbruster <armbru@redhat.com> writes:

> Eric Blake <eblake@redhat.com> writes:
>
>> On 3/23/21 4:40 AM, Markus Armbruster wrote:
>>> Naming rules differ for the various kinds of names.  To prepare
>>> enforcing them, define functions to check them: check_name_upper(),
>>> check_name_lower(), and check_name_camel().  For now, these merely
>>> wrap around check_name_str(), but that will change shortly.  Replace
>>> the other uses of check_name_str() by appropriate uses of the
>>> wrappers.  No change in behavior just yet.
>>> 
>>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>>> ---
>>>  scripts/qapi/expr.py | 51 +++++++++++++++++++++++++++++++-------------
>>>  1 file changed, 36 insertions(+), 15 deletions(-)
>>> 
>>
>>> +++ b/scripts/qapi/expr.py
>>> @@ -21,11 +21,12 @@
>>>  from .error import QAPISemError
>>>  
>>>  
>>> -# Names must be letters, numbers, -, and _.  They must start with letter,
>>> -# except for downstream extensions which must start with __RFQDN_.
>>> -# Dots are only valid in the downstream extension prefix.
>>> -valid_name = re.compile(r'^(__[a-zA-Z0-9.-]+_)?'
>>> -                        '[a-zA-Z][a-zA-Z0-9_-]*$')
>>
>> I'm assuming python concatenates r'' with '' in the obvious manner...
>>
>>> +# Names consist of letters, digits, -, and _, starting with a letter.
>>> +# An experimental name is prefixed with x-.  A name of a downstream
>>> +# extension is prefixed with __RFQDN_.  The latter prefix goes first.
>>> +valid_name = re.compile(r'(__[a-z0-9.-]+_)?'
>>> +                        r'(x-)?'
>>> +                        r'([a-z][a-z0-9_-]*)$', re.IGNORECASE)
>>
>> ...but like your explicit use of r'' r''.
>>
>> Splitting out special handling of r'(x-)?' does not change behavior, but
>> is not otherwise mentioned in your commit message.  I suspect you did it
>> to make it easier to permit x-EVENT_NAME in later patches where upper is
>> handled differently from lower or camel,
>
> Yes.
>
>>                                          so I won't withhold R-b, but it
>> may be worth a tweak to the commit message.
>
> Probably.  I'm failing at coming up with a concise text that isn't
> confusing.

Adding this paragraph:

    check_name_str() now returns the name without downstream and x-
    prefix, for use by the wrappers in later patches.  Requires tweaking
    regexp @valid_name.  It accepts the same strings as before.