Re: [PATCH v3 12/47] qapi: enforce import order/styling with isort

[John Snow <jsnow@redhat.com>]

On 9/25/20 5:20 AM, Markus Armbruster wrote:
> John Snow <jsnow@redhat.com> writes:
> 
>> While we're mucking around with imports, we might as well formalize the
>> style we use. Let's use isort to do it for us.
>>
>> force_sort_within_sections: Intermingles "from x" and "import x" style
>> statements, such that sorting is always performed strictly on the module
>> name itself.
>>
>> force_grid_wrap=4: Four or more imports from a single module will force
>> the one-per-line style that's more git-friendly. This will generally
>> happen for 'typing' imports.
>>
>> multi_line_output=3: Uses the one-per-line indented style for long
>> imports.
>>
>> include_trailing_comma: Adds a comma to the last import in a group,
>> which makes git conflicts nicer to deal with, generally.
>>
>> Suggested-by: Cleber Rosa <crosa@redhat.com>
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>>   scripts/qapi/.isort.cfg    | 5 +++++
>>   scripts/qapi/commands.py   | 6 +-----
>>   scripts/qapi/doc.py        | 2 +-
>>   scripts/qapi/expr.py       | 4 ++--
>>   scripts/qapi/introspect.py | 3 +--
>>   scripts/qapi/main.py       | 1 -
>>   scripts/qapi/parser.py     | 2 +-
>>   scripts/qapi/schema.py     | 2 +-
>>   scripts/qapi/types.py      | 1 -
>>   9 files changed, 12 insertions(+), 14 deletions(-)
>>   create mode 100644 scripts/qapi/.isort.cfg
>>
>> diff --git a/scripts/qapi/.isort.cfg b/scripts/qapi/.isort.cfg
>> new file mode 100644
>> index 0000000000..b0aeffec26
>> --- /dev/null
>> +++ b/scripts/qapi/.isort.cfg
>> @@ -0,0 +1,5 @@
>> +[settings]
>> +force_sort_within_sections=True
>> +force_grid_wrap=4
>> +multi_line_output=3
>> +include_trailing_comma=True
>> diff --git a/scripts/qapi/commands.py b/scripts/qapi/commands.py
>> index e1df0e341f..64ed5278f9 100644
>> --- a/scripts/qapi/commands.py
>> +++ b/scripts/qapi/commands.py
>> @@ -13,11 +13,7 @@
>>   See the COPYING file in the top-level directory.
>>   """
>>   
>> -from .common import (
>> -    build_params,
>> -    c_name,
>> -    mcgen,
>> -)
>> +from .common import build_params, c_name, mcgen
>>   from .gen import QAPIGenCCode, QAPISchemaModularCVisitor, ifcontext
> 
> Squash this hunk into the previous commit, please.
> 

Yes, OK.

>>   
>>   
>> diff --git a/scripts/qapi/doc.py b/scripts/qapi/doc.py
>> index b764a8ccc0..1acb773e0a 100644
>> --- a/scripts/qapi/doc.py
>> +++ b/scripts/qapi/doc.py
>> @@ -5,9 +5,9 @@
>>   """This script produces the documentation of a qapi schema in texinfo format"""
>>   
>>   import re
>> +
>>   from .gen import QAPIGenDoc, QAPISchemaVisitor
>>   
>> -
> 
> Do you delete the blank line to keep isort happy?
> 

isort offers to actually edit your files for you, it isn't just a 
checker, it actually rewrites.

By default, it leaves one space below imports. You can configure it to 
add two. I didn't really have a strong preference, so I left it at the 
default.

I'm going to leave it at the default for now, but I can change it if you 
have a preference.

> More of the same below.
> 
>>   _MSG = '''
>>   @deftypefn {type} {{}} {name}
>>   
>> diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py
>> index 03b31ecfc1..3e952a1462 100644
>> --- a/scripts/qapi/expr.py
>> +++ b/scripts/qapi/expr.py
>> @@ -14,12 +14,12 @@
>>   # This work is licensed under the terms of the GNU GPL, version 2.
>>   # See the COPYING file in the top-level directory.
>>   
>> -import re
>>   from collections import OrderedDict
>> +import re
>> +
>>   from .common import c_name
>>   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.
>> diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
>> index b036fcf9ce..2850121cbd 100644
>> --- a/scripts/qapi/introspect.py
>> +++ b/scripts/qapi/introspect.py
>> @@ -17,8 +17,7 @@
>>       mcgen,
>>   )
>>   from .gen import QAPISchemaMonolithicCVisitor
>> -from .schema import (QAPISchemaArrayType, QAPISchemaBuiltinType,
>> -                     QAPISchemaType)
>> +from .schema import QAPISchemaArrayType, QAPISchemaBuiltinType, QAPISchemaType
> 
> Line is rather long for my taste.
> 

78 chars and three names, so it didn't trigger the grid-wrap condition 
of isort.

If you have an arbitrarily smaller number you'd like to use, I can feed 
that to isort's config file. 72?

> So far, we didn't even try to have a consistent Python style in QEMU, so
> I've enforced a consistent style I like within QAPI.
> 

I am now trying!

> Having a consistent Python style in QEMU would be worth letting go of
> personal preferences.  Do you intend to pursue it?
> 

100%.

--js