On 4/15/21 3:15 AM, Markus Armbruster wrote:
> John Snow <jsnow@redhat.com> writes:
>
>> No functional change.
>>
>> Signed-off-by: John Snow <jsnow@redhat.com>
>> ---
>> scripts/qapi/error.py | 11 +++++++++--
>> 1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/scripts/qapi/error.py b/scripts/qapi/error.py
>> index 2183b8c6b7..6ba54821c9 100644
>> --- a/scripts/qapi/error.py
>> +++ b/scripts/qapi/error.py
>> @@ -11,6 +11,10 @@
>> # This work is licensed under the terms of the GNU GPL, version 2.
>> # See the COPYING file in the top-level directory.
>>
>> +from typing import Optional
>> +
>> +from .source import QAPISourceInfo
>> +
>>
>> class QAPIError(Exception):
>> """Base class for all exceptions from the QAPI package."""
>> @@ -18,13 +22,16 @@ class QAPIError(Exception):
>>
>> class QAPISourceError(QAPIError):
>> """Error class for all exceptions identifying a source location."""
>> - def __init__(self, info, msg, col=None):
>> + def __init__(self,
>> + info: Optional[QAPISourceInfo],
>
> The Optional is a bit surprising. Mind pointing to the / a reason in
> the commit message?
>
We don't have a special object representing "No Source Info", so
schema.py passes around None objects to mean the same.
The problem, ultimately, is that a QAPISchemaEntity may or may not have
a source info; and various error reporting paths that in practice will
not involve such a type in its reporting cannot distinguish that using
the type system, because from the root-down, info is codified as
Optional[QAPISourceInfo].
There might be a way to introduce a constraint in schema.py later on,
but for now (prior to part 6, especially), we cannot.
The assertion should help remind a reader that we don't expect it to be
true.
--js
>> + msg: str,
>> + col: Optional[int] = None):
>> super().__init__()
>> self.info = info
>> self.msg = msg
>> self.col = col
>>
>> - def __str__(self):
>> + def __str__(self) -> str:
>> assert self.info is not None
>> loc = str(self.info)
>> if self.col is not None: