subprocess stdout read1

[Akuli]

import subprocess
process = subprocess.Popen("echo hello", shell=True, stdout=subprocess.PIPE)
assert process.stdout is not None
print(process.stdout.read1())

mypy error:

asd.py:4: error: "IO[bytes]" has no attribute "read1"; maybe "read"?
Found 1 error in 1 file (checked 1 source file)

But at runtime there is read1() method. It is useful because unlike read(), it will return the output as soon as it is available, instead of reading more until it gets n bytes or end of file.

[JelleZijlstra]

We should use the concrete runtime types in the subprocess stubs instead of IO[bytes]. I just tried and it's an _io.BufferedReader for me, but not sure whether that's always the case.