/usr/local/lib/python3.10/dist-packages/rti/connextdds/__init__.pyi:18332:17:18332:17: error: invalid syntax [syntax]

[jzenoz]

Bug Report

Seems like the same bug as:
pylint-dev/pylint#9585

But not sure if there's a common library function. Basically mypy throws an "invalid syntax" error when trying to process the init.pyi autogenerated file from the rti.connext module.

To Reproduce

Playground gives a 520 error when trying to process the ~42k line file.

pip install rti.connext==7.3.0 mypy==1.15.0

hello.py:

import rti.types as idl

@idl.struct
class HelloWorld:
    message: str = ""

hello_publisher.py:

import time
import rti.connextdds as dds
from hello import HelloWorld

participant = dds.DomainParticipant(domain_id=0)
topic = dds.Topic(participant, 'HelloWorld Topic', HelloWorld)
writer = dds.DataWriter(participant.implicit_publisher, topic)

for i in range(10):
    writer.write(HelloWorld(message=f'Hello World! #{i}'))
    time.sleep(1)

hello_subscriber.py:

import rti.connextdds as dds
import rti.asyncio
from hello import HelloWorld

participant = dds.DomainParticipant(domain_id=0)
topic = dds.Topic(participant, 'HelloWorld Topic', HelloWorld)
reader = dds.DataReader(participant.implicit_subscriber, topic)

async def print_data():
    async for data in reader.take_data_async():
        print(f"Received: {data}")

rti.asyncio.run(print_data())

mypy  --follow-untyped-imports --pretty .
/home/jz/.local/lib/python3.12/site-packages/rti/connextdds/__init__.pyi:35732:31: error: invalid syntax  [syntax]
        def type(self) -> detail::accessor<detail::accessor_policies::str_attr>:
                                  ^
Found 1 error in 1 file (errors prevented further checking)

The title of this issue is the output from the vscode extension which oddly matches this issue on pylint side:
pylint-dev/pylint#9585

Actual Behavior

/home/jz/.local/lib/python3.12/site-packages/rti/connextdds/__init__.pyi:35732:31: error: invalid syntax  [syntax]
        def type(self) -> detail::accessor<detail::accessor_policies::str_attr>:
                                  ^
Found 1 error in 1 file (errors prevented further checking)

Also the output from the vscode plugin:

2025-04-05 20:11:23.411 [info] [Trace - 8:11:23 PM] Received notification 'window/logMessage'.
2025-04-05 20:11:23.411 [info] file:///home/jz/scratch/hello.py :
/usr/local/lib/python3.10/dist-packages/rti/connextdds/__init__.pyi:18332:17:18332:17: error: invalid syntax  [syntax]

Your Environment

• Mypy version used: 1.15.0
• Mypy command-line flags: --follow-untyped-imports
• Mypy configuration options from mypy.ini (and other config files): N/A
• Python version used: 3.12.3

init.zip

[brianschubert]

Thanks for the report. However, there isn't anything mypy can do here. def type(self) -> detail::accessor<detail::accessor_policies::str_attr>: is indeed invalid Python syntax. I verified that that line is present in the stub file. You'll need to report this to the project that's generating the invalid stub file.

[jzenoz]

@brianschubert Is line 18332 from the vscode plugin error also a valid syntax error?

class ItemsView[StringMap]():
    def __iter__(self) -> typing.Iterator: ...
    def __len__(self) -> int: ...
    pass

[brianschubert]

That looks fine (assuming PEP 695 generic syntax is supported). If it's complaining about a syntax error there, the issue may be in the lines immediately before it

[jzenoz]

@brianschubert is the first syntax error strictly typing-wise/not runtime enforced? Because this module is used widely, by many many companies, in production.

[brianschubert]

Yes, stub files are not used at runtime. But they do need to have valid syntax to be interpretable by static analysis tools (like mypy and pylint).