Re: [PATCH v5 17/36] qapi/common.py: move build_params into gen.py

[Markus Armbruster <armbru@redhat.com>]

John Snow <jsnow@redhat.com> writes:

> Including it in common.py creates a circular import dependency; schema
> relies on common, but common.build_params requires a type annotation
> from schema. To type this properly, it needs to be moved outside the
> cycle.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
> Reviewed-by: Cleber Rosa <crosa@redhat.com>
> ---
>  scripts/qapi/commands.py |  9 +++++++--
>  scripts/qapi/common.py   | 23 -----------------------
>  scripts/qapi/events.py   |  9 ++-------
>  scripts/qapi/gen.py      | 31 +++++++++++++++++++++++++++++--
>  4 files changed, 38 insertions(+), 34 deletions(-)
>
> diff --git a/scripts/qapi/commands.py b/scripts/qapi/commands.py
> index 5dc2f5a9fa8..f67393f8713 100644
> --- a/scripts/qapi/commands.py
> +++ b/scripts/qapi/commands.py
> @@ -13,8 +13,13 @@
>  See the COPYING file in the top-level directory.
>  """
>  
> -from .common import build_params, c_name, mcgen
> -from .gen import QAPIGenCCode, QAPISchemaModularCVisitor, ifcontext
> +from .common import c_name, mcgen
> +from .gen import (
> +    QAPIGenCCode,
> +    QAPISchemaModularCVisitor,
> +    build_params,
> +    ifcontext,
> +)
>  
>  
>  def gen_command_decl(name, arg_type, boxed, ret_type):
> diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
> index 0ef38ea5fe0..9ab0685cc51 100644
> --- a/scripts/qapi/common.py
> +++ b/scripts/qapi/common.py
> @@ -209,26 +209,3 @@ def gen_endif(ifcond: Sequence[str]) -> str:
>  #endif /* %(cond)s */
>  ''', cond=ifc)
>      return ret
> -
> -
> -def build_params(arg_type,
> -                 boxed: bool,
> -                 extra: Optional[str] = None) -> str:
> -    ret = ''
> -    sep = ''
> -    if boxed:
> -        assert arg_type
> -        ret += '%s arg' % arg_type.c_param_type()
> -        sep = ', '
> -    elif arg_type:
> -        assert not arg_type.variants
> -        for memb in arg_type.members:
> -            ret += sep
> -            sep = ', '
> -            if memb.optional:
> -                ret += 'bool has_%s, ' % c_name(memb.name)
> -            ret += '%s %s' % (memb.type.c_param_type(),
> -                              c_name(memb.name))
> -    if extra:
> -        ret += sep + extra
> -    return ret if ret else 'void'
> diff --git a/scripts/qapi/events.py b/scripts/qapi/events.py
> index 6b3afa14d72..f840a62ed92 100644
> --- a/scripts/qapi/events.py
> +++ b/scripts/qapi/events.py
> @@ -12,13 +12,8 @@
>  See the COPYING file in the top-level directory.
>  """
>  
> -from .common import (
> -    build_params,
> -    c_enum_const,
> -    c_name,
> -    mcgen,
> -)
> -from .gen import QAPISchemaModularCVisitor, ifcontext
> +from .common import c_enum_const, c_name, mcgen
> +from .gen import QAPISchemaModularCVisitor, build_params, ifcontext
>  from .schema import QAPISchemaEnumMember
>  from .types import gen_enum, gen_enum_lookup
>  
> diff --git a/scripts/qapi/gen.py b/scripts/qapi/gen.py
> index 1fed712b43b..f2e2746fea5 100644
> --- a/scripts/qapi/gen.py
> +++ b/scripts/qapi/gen.py
> @@ -2,9 +2,11 @@
>  #
>  # QAPI code generation
>  #
> -# Copyright (c) 2018-2019 Red Hat Inc.
> +# Copyright IBM, Corp. 2011
> +# Copyright (c) 2013-2019 Red Hat Inc.
>  #
>  # Authors:
> +#  Anthony Liguori <aliguori@us.ibm.com>
>  #  Markus Armbruster <armbru@redhat.com>
>  #  Marc-André Lureau <marcandre.lureau@redhat.com>
>  #

The code you move into this file is actually Red Hat's:

$ git-log -L174,193:scripts/qapi/common.py master| egrep 'Author|Date'
Author: Markus Armbruster <armbru@redhat.com>
Date:   Wed Aug 15 21:37:36 2018 +0800
Author: Marc-André Lureau <marcandre.lureau@redhat.com>
Date:   Thu Jun 1 16:41:41 2017 +0400
Author: Eric Blake <eblake@redhat.com>
Date:   Wed Jul 13 21:50:20 2016 -0600
Author: Eric Blake <eblake@redhat.com>
Date:   Wed Jul 13 21:50:19 2016 -0600
Author: Eric Blake <eblake@redhat.com>
Date:   Thu Mar 17 16:48:28 2016 -0600
Author: Markus Armbruster <armbru@redhat.com>
Date:   Wed Sep 16 13:06:20 2015 +0200

So the correct update is simply

   #
   # QAPI code generation
   #
  -# Copyright (c) 2018-2019 Red Hat Inc.
  +# Copyright (c) 2015-2019 Red Hat Inc.
   #
   # Authors:
   #  Markus Armbruster <armbru@redhat.com>
   #  Marc-André Lureau <marcandre.lureau@redhat.com>
   #

> @@ -15,16 +17,18 @@
>  import errno
>  import os
>  import re
> +from typing import Optional
>  
>  from .common import (
>      c_fname,
> +    c_name,
>      gen_endif,
>      gen_if,
>      guardend,
>      guardstart,
>      mcgen,
>  )
> -from .schema import QAPISchemaVisitor
> +from .schema import QAPISchemaObjectType, QAPISchemaVisitor
>  
>  
>  class QAPIGen:
> @@ -90,6 +94,29 @@ def _wrap_ifcond(ifcond, before, after):
>      return out
>  
>  
> +def build_params(arg_type: Optional[QAPISchemaObjectType],
> +                 boxed: bool,
> +                 extra: Optional[str] = None) -> str:
> +    ret = ''
> +    sep = ''
> +    if boxed:
> +        assert arg_type
> +        ret += '%s arg' % arg_type.c_param_type()
> +        sep = ', '
> +    elif arg_type:
> +        assert not arg_type.variants
> +        for memb in arg_type.members:
> +            ret += sep
> +            sep = ', '
> +            if memb.optional:
> +                ret += 'bool has_%s, ' % c_name(memb.name)
> +            ret += '%s %s' % (memb.type.c_param_type(),
> +                              c_name(memb.name))
> +    if extra:
> +        ret += sep + extra
> +    return ret if ret else 'void'
> +
> +
>  class QAPIGenCCode(QAPIGen):
>  
>      def __init__(self, fname):