Re: [Qemu-devel] [PATCH v2 01/54] qapi: fix type_seen key error

[Markus Armbruster]

Marc-André Lureau <address@hidden> writes:

> The type_seen member can be of a different type than the 'qtype' being
> checked, since a string create several conflicts. Lookup the real
> conflicting type in the conflict set, that one must be present in
> type_seen.
>
> This fixes the following error, reproducible with the modified test:
>
> Traceback (most recent call last):
>   File "/home/elmarco/src/qq/tests/qapi-schema/test-qapi.py", line 56, in 
> <module>
>     schema = QAPISchema(sys.argv[1])
>   File "/home/elmarco/src/qq/scripts/qapi.py", line 1470, in __init__
>     self.exprs = check_exprs(parser.exprs)
>   File "/home/elmarco/src/qq/scripts/qapi.py", line 959, in check_exprs
>     check_alternate(expr, info)
>   File "/home/elmarco/src/qq/scripts/qapi.py", line 831, in check_alternate
>     % (name, key, types_seen[qtype]))
> KeyError: 'QTYPE_QSTRING'
>
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  scripts/qapi.py                                  | 6 ++++--
>  tests/qapi-schema/alternate-conflict-string.json | 4 ++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/scripts/qapi.py b/scripts/qapi.py
> index 8aa2775f12..a3ac799535 100644
> --- a/scripts/qapi.py
> +++ b/scripts/qapi.py
> @@ -825,10 +825,12 @@ def check_alternate(expr, info):
>              else:
>                  conflicting.add('QTYPE_QNUM')
>                  conflicting.add('QTYPE_QBOOL')
> -        if conflicting & set(types_seen):
> +        conflict = conflicting & set(types_seen)
> +        if conflict:
> +            conflict_qtype = list(conflict)[0]

Converting from set to list just to extract an element is clumsly.
Let's use conflict.pop(), and eliminate the variable.  Can do on commit.

>              raise QAPISemError(info, "Alternate '%s' member '%s' can't "
>                                 "be distinguished from member '%s'"
> -                               % (name, key, types_seen[qtype]))
> +                               % (name, key, types_seen[conflict_qtype]))
>          for qt in conflicting:
>              types_seen[qt] = key
>  
> diff --git a/tests/qapi-schema/alternate-conflict-string.json 
> b/tests/qapi-schema/alternate-conflict-string.json
> index 85adbd4adc..bb2702978e 100644
> --- a/tests/qapi-schema/alternate-conflict-string.json
> +++ b/tests/qapi-schema/alternate-conflict-string.json
> @@ -1,4 +1,4 @@
>  # alternate branches of 'str' type conflict with all scalar types
>  { 'alternate': 'Alt',
> -  'data': { 'one': 'str',
> -            'two': 'int' } }
> +  'data': { 'one': 'int',
> +            'two': 'str' } }

Reviewed-by: Markus Armbruster <address@hidden>