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

[John Snow <jsnow@redhat.com>]

On 3/25/21 2:18 AM, Markus Armbruster wrote:
> John Snow <jsnow@redhat.com> writes:
> 
>> On 3/24/21 1:57 AM, Markus Armbruster wrote:
>>> John Snow <jsnow@redhat.com> writes:
>>>
>>>> On 3/23/21 5:40 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(-)
>>>>> diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py
>>>>> index e00467636c..30285fe334 100644
>>>>> --- a/scripts/qapi/expr.py
>>>>> +++ 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_-]*$')
>>>>> +# Names consist of letters, digits, -, and _, starting with a letter.
>>>>> +# An experimental name is prefixed with x-.  A name of a downstream
>>>>> +# extension is prefixed with __RFQDN_.  The latter prefix goes first.
>>>>> +valid_name = re.compile(r'(__[a-z0-9.-]+_)?'
>>>>> +                        r'(x-)?'
>>>>> +                        r'([a-z][a-z0-9_-]*)$', re.IGNORECASE)
>>>>>          def check_name_is_str(name, info, source):
>>>>> @@ -37,16 +38,38 @@ def check_name_str(name, info, source,
>>>>>                        permit_upper=False):
>>>>>         # Reserve the entire 'q_' namespace for c_name(), and for 'q_empty'
>>>>>         # and 'q_obj_*' implicit type names.
>>>>> -    if not valid_name.match(name) or \
>>>>> -       c_name(name, False).startswith('q_'):
>>>>> +    match = valid_name.match(name)
>>>>> +    if not match or c_name(name, False).startswith('q_'):
>>>>>             raise QAPISemError(info, "%s has an invalid name" % source)
>>>>>         if not permit_upper and name.lower() != name:
>>>>>             raise QAPISemError(
>>>>>                 info, "%s uses uppercase in name" % source)
>>>>> +    return match.group(3)
>>>>> +
>>>>> +
>>>>> +def check_name_upper(name, info, source):
>>>>> +    stem = check_name_str(name, info, source, permit_upper=True)
>>>>> +    # TODO reject '[a-z-]' in @stem
>>>>> +
>>>>
>>>> Creates (presumably) temporary errors in flake8 for the dead
>>>> assignment here and below.
>>>
>>> All gone by the end of the series.
>>>
>>> "make check" and checkpatch were content.  Anything else you'd like me
>>> to run?
>>
>> Eventually it'll be part of CI, with targets to run locally.
>>
>> I never expected the process to take this long, so I did not invest my
>> time in developing an interim solution.
>>
>> I use a hastily written script to do my own testing, which I run for
>> every commit that touches QAPI:
>>
>> #!/usr/bin/env bash
>> set -e
>>
>> if [[ -f qapi/.flake8 ]]; then
>>      echo "flake8 --config=qapi/.flake8 qapi/"
>>      flake8 --config=qapi/.flake8 qapi/
>> fi
>> if [[ -f qapi/pylintrc ]]; then
>>      echo "pylint --rcfile=qapi/pylintrc qapi/"
>>      pylint --rcfile=qapi/pylintrc qapi/
>> fi
>> if [[ -f qapi/mypy.ini ]]; then
>>      echo "mypy --config-file=qapi/mypy.ini qapi/"
>>      mypy --config-file=qapi/mypy.ini qapi/
>> fi
>>
>> if [[ -f qapi/.isort.cfg ]]; then
>>      pushd qapi
>>      echo "isort -c ."
>>      isort -c .
>>      popd
>> fi
>>
>> pushd ../bin/git
>> make -j9
>> make check-qapi-schema
>> popd
> 
> Thanks for sharing this!
> 

My intent, eventually, was to get scripts/qapi under python/qemu/qapi; 
under which there is a testing framework thing I have been debating on 
and off with Cleber for a while that does (basically) the same thing as 
what my hasty script does, but more integrated with Python ecosystem.

It'll do a few things:

(1) Gets these checks on CI
(2) Allows developers to manually run the checks locally
(3) Allows developers to manually run the checks locally using a 
pre-determined set of pinned linter versions to guarantee synchronicity 
with CI

cd python/qemu && "make check" would do more or less the same as the 
hacky script above, "make venv-check" would create a virtual environment 
with precisely the right packages and then run the same.

I have been stalled there for a while, and I missed freeze deadline from 
illness. Anguish. For now, the dumb script in my scripts directory does 
the lifting I need it to, using packages I have selected in my local 
environment that just-so-happen to pass.

> Apropos qapi-gen testing scripts.  I have scripts to show me how the
> generated code changes along the way in a branch.  They evolved over a
> long time, and try to cope with changes in the tree that are hardly
> relevant anymore.  By now, they could quite possibly make Frankenstein
> recoil in horror.
> 

Are they in the tree? Largely if the generated code changes it's 
invisible to me, but I rely heavily on the unit tests. I guess maybe if 
they are not in a state to upstream it might not be worth the hassle to 
clean them, but I don't know.

> As a secondary purpose, the scripts show me how output of pycodestyle-3
> and pylint change.  This would be uninteresting if the code in master
> was clean against a useful configuration of these tools.  Your work has
> been making it less interesting.
> 

--js