io.UnsupportedOperation when using rez api with pytest

[spsalefeve]

Hi,

I have the following issue when using rez API in my tests with pytest:

2020-10-08 09:27:59,859|setcontext|solve_util|l. 465| ERROR| Context couldn't be resolved.
Traceback (most recent call last):
  File "/app/package/int/setcontext/current/python/setcontext/solve_util.py", line 460, in _resolve
    resolved_context = ResolvedContext(package_list, **kwargs)
  File "/app/package/ext/rez/current/python/rez/resolved_context.py", line 208, in __init__
    for x in config.implicit_packages]
  File "/app/package/ext/rez/current/python/rez/utils/data_utils.py", line 191, in __get__
    result = self.func(instance)
  File "/app/package/ext/rez/current/python/rez/utils/data_utils.py", line 587, in getter
    return self._validate_key(key, attr, key_schema)
  File "/app/package/ext/rez/current/python/rez/config.py", line 614, in _validate_key
    return key_schema.validate(value)
  File "/app/package/ext/rez/current/python/rez/config.py", line 54, in validate
    data = expand_system_vars(data)
  File "/app/package/ext/rez/current/python/rez/config.py", line 783, in expand_system_vars
    return _expanded(data)
  File "/app/package/ext/rez/current/python/rez/config.py", line 778, in _expanded
    return [_expanded(x) for x in value]
  File "/app/package/ext/rez/current/python/rez/config.py", line 778, in <listcomp>
    return [_expanded(x) for x in value]
  File "/app/package/ext/rez/current/python/rez/config.py", line 776, in _expanded
    return scoped_format(value, system=system)
  File "/app/package/ext/rez/current/python/rez/utils/scope.py", line 262, in scoped_format
    return formatter.format(txt, pretty=pretty, expand=expand)
  File "/app/package/ext/rez/current/python/rez/utils/formatting.py", line 182, in format
    return formatter.format(s)
  File "/usr/local/lib/python3.7/string.py", line 186, in format
    return self.vformat(format_string, args, kwargs)
  File "/usr/local/lib/python3.7/string.py", line 190, in vformat
    result, _ = self._vformat(format_string, args, kwargs, used_args, 2)
  File "/usr/local/lib/python3.7/string.py", line 230, in _vformat
    obj, arg_used = self.get_field(field_name, args, kwargs)
  File "/app/package/ext/rez/current/python/rez/utils/formatting.py", line 117, in get_field
    return Formatter.get_field(self, field_name, args, kwargs)
  File "/usr/local/lib/python3.7/string.py", line 301, in get_field
    obj = getattr(obj, i)
  File "/app/package/ext/rez/current/python/rez/utils/data_utils.py", line 191, in __get__
    result = self.func(instance)
  File "/app/package/ext/rez/current/python/rez/system.py", line 52, in os
    r = platform_.os
  File "/app/package/ext/rez/current/python/rez/utils/data_utils.py", line 191, in __get__
    result = self.func(instance)
  File "/app/package/ext/rez/current/python/rez/utils/platform_mapped.py", line 31, in inner
    result = func(*args, **kwargs)
  File "/app/package/ext/rez/current/python/rez/utils/platform_.py", line 33, in os
    return self._os()
  File "/app/package/ext/rez/current/python/rez/utils/platform_.py", line 231, in _os
    stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True
  File "/app/package/ext/rez/current/python/rez/utils/execution.py", line 54, in __init__
    file_no = sys.stdin.fileno()
  File "/app/package/ext/pytest/6.0.2/0195e0b9d4f737afb12e188f1abf4b9e01abb774/python/_pytest/capture.py", line 228, in fileno
    raise UnsupportedOperation("redirected stdin is pseudofile, has no fileno()")
io.UnsupportedOperation: redirected stdin is pseudofile, has no fileno()

Rez version : 2.68.4
Platform and operating system: Linux CentOS 7.6.1810
Contextual information:

• Create a file test_main.py with the following content:

#!/usr/bin/env python
# coding: utf-8
"""Test rez log."""
from rez.resolved_context import ResolvedContext

def test_rez_log():
    # You can use another package you have
    context = ResolvedContext(["python"])
    print(context)

test_rez_log()

• Run the script with rez API in the environment (I have rez API as a rez package) :

rez env rez --  ./test_main.py

Here is my result:

solved(python ~platform==linux ~arch==64bit ~os==CentOS-7.6.1810 pyarmor_runtime ==> platform-linux[] arch-64bit[] os-CentOS-7.6.1810[] python-3.7-sps.1.1[0] pyarmor_runtime-0.3.0[0])

• Now try to run it as a pytest test:

rez env pytest pytest -- python -m pytest ./test_main.py

You should see the error appear. I will propose a Pull Request about this.

[nerdvegas]

fixed by #966