On 5/27/19 9:24 AM, Max Reitz wrote:
> On 24.05.19 20:02, John Snow wrote:
>> Before, event_match didn't always recurse if the event value was not a
>> dictionary, and would instead check for equality immediately.
>>
>> By delaying equality checking to post-recursion, we can allow leaf
>> values like "5" to match "None" and take advantage of the generic
>> None-returns-True clause.
>>
>> This makes the matching a little more obviously consistent at the
>> expense of being able to check for explicit None values, which is
>> probably not that important given what this function is used for.
>>
>> Signed-off-by: John Snow <js...@redhat.com>
>> ---
>> python/qemu/__init__.py | 27 +++++++++++++++------------
>> 1 file changed, 15 insertions(+), 12 deletions(-)
>>
>> diff --git a/python/qemu/__init__.py b/python/qemu/__init__.py
>> index 98ed8a2e28..77d45f88fe 100644
>> --- a/python/qemu/__init__.py
>> +++ b/python/qemu/__init__.py
>> @@ -409,27 +409,30 @@ class QEMUMachine(object):
>>
>> The match criteria takes the form of a matching subdict. The event
>> is
>> checked to be a superset of the subdict, recursively, with matching
>> - values whenever those values are not None.
>> + values whenever the subdict values are not None.
>> +
>> + This has a limitation that you cannot explicitly check for None
>> values.
>>
>> Examples, with the subdict queries on the left:
>> - None matches any object.
>> - {"foo": None} matches {"foo": {"bar": 1}}
>> - - {"foo": {"baz": None}} does not match {"foo": {"bar": 1}}
>> - - {"foo": {"baz": 2}} matches {"foo": {"bar": 1, "baz": 2}}
>> + - {"foo": None} matches {"foo": 5}
>> + - {"foo": {"abc": None}} does not match {"foo": {"bar": 1}}
>> + - {"foo": {"rab": 2}} matches {"foo": {"bar": 1, "rab": 2}}
>> """
>> if match is None:
>> return True
>>
>> - for key in match:
>> - if key in event:
>> - if isinstance(event[key], dict):
>> - if not QEMUMachine.event_match(event[key], match[key]):
>> - return False
>> - elif event[key] != match[key]:
>> + try:
>> + for key in match:
>> + if key in event:
>> + return QEMUMachine.event_match(event[key], match[key])
>
> With this change, we only check a single key that is both in @match and
> @event. I think we want to keep the "if not -- return False" pattern,
> don’t we?
>
> Max
>
Whoops, way too fast on the send button. Sorry about that.
