SubprocessCommand - `libvcs._internal.subprocess`¶

Invocable subprocess wrapper.

Defer running a subprocess, such as by handing to an executor.

Note

This is an internal API not covered by versioning policy.

Examples

SubprocessCommand: Wraps subprocess.Popen and subprocess.run() in a dataclass().

Before:

>>> import subprocess
>>> subprocess.run(
...    ['echo', 'hi'],
...    capture_output=True, universal_newlines=True
... ).stdout
'hi\n'

With this:

>>> cmd = SubprocessCommand(['echo', 'hi'])
>>> cmd.args
['echo', 'hi']
>>> cmd.run(capture_output=True, universal_newlines=True).stdout
'hi\n'

Tweak params before invocation:

>>> cmd = SubprocessCommand(['echo', 'hi'])
>>> cmd.args[1] = 'hello'
>>> cmd.args
['echo', 'hello']
>>> cmd.run(capture_output=True, universal_newlines=True).stdout
'hello\n'

exception libvcs._internal.subprocess.SubprocessCheckOutputError ¶ exception[source]

Bases: Exception

libvcs._internal.subprocess._CMD: TypeAlias = str | bytes | os.PathLike[str] | os.PathLike[bytes] | collections.abc.Sequence[str | bytes | os.PathLike[str] | os.PathLike[bytes]] ¶ data: Command

class libvcs._internal.subprocess.SubprocessCommand ¶ class[source]

Bases: SkipDefaultFieldsReprMixin

Wraps a subprocess request. Inspect, mutate, control before invocation.

Examples

>>> cmd = SubprocessCommand("ls")
>>> cmd.args
'ls'

With shell=True:

>>> cmd = SubprocessCommand("ls -l", shell=True)
>>> cmd.shell
True
>>> cmd.args
'ls -l'
>>> cmd.check_call()
0

__init__(args, bufsize=-1, executable=None, stdin=None, stdout=None, stderr=None, preexec_fn=None, close_fds=True, shell=False, cwd=None, env=None, creationflags=0, startupinfo=None, restore_signals=True, start_new_session=False, pass_fds=(), umask=-1, pipesize=-1, user=None, group=None, extra_groups=None, universal_newlines=None, text=None, encoding=None, errors=None) ¶ method[source]

Parameters:

args (_CMD)
bufsize (int)
executable (StrOrBytesPath | None)
stdin (_FILE)
stdout (_FILE)
stderr (_FILE)
preexec_fn (Callable[[], Any] | None)
close_fds (bool)
shell (bool)
cwd (StrOrBytesPath | None)
env (_ENV | None)
creationflags (int)
startupinfo (Any | None)
restore_signals (bool)
start_new_session (bool)
pass_fds (Any)
umask (int)
pipesize (int)
user (str | None)
group (str | None)
extra_groups (list[str] | None)
universal_newlines (bool | None)
text (Literal[True] | None)
encoding (str | None)
errors (str | None)

Return type:

None

Run commands subprocess.Popen, optionally overrides via kwargs.

Parameters:: **kwargs (dict, optional) – Overrides existing attributes for subprocess.Popen

Examples

>>> cmd = SubprocessCommand(args=['echo', 'hello'])
>>> proc = cmd.Popen(stdout=subprocess.PIPE)
>>> proc.communicate()

check_output(universal_newlines: bool = None, *, input: str | bytes | None = None, encoding: str | None = None, errors: str | None = None, text: Literal[True], **kwargs: Any) → str
¶
method[source]

check_output(universal_newlines: bool = None, *, input: str | bytes | None = None, encoding: str | None = None, errors: str, text: bool | None = None, **kwargs: Any) → str
method

check_output(universal_newlines: Literal[False], *, input: str | bytes | None = None, encoding: None = None, errors: None = None, text: Literal[False] | None = None, **kwargs: Any) → bytes
method

Run command subprocess.check_output(), optionally override via kwargs.

Parameters:

input (t.Union[bytes, str], optional) –
pass string to subprocess’s stdin. Bytes by default, str in text mode.

Text mode is triggered by setting any of text, encoding, errors or universal_newlines.
**kwargs (dict, optional) – Overrides existing attributes for subprocess.check_output()

Examples

>>> cmd = SubprocessCommand(args=['echo', 'hello'])
>>> proc = cmd.check_output(shell=True)

Examples from subprocess:

>>> import subprocess
>>> cmd = SubprocessCommand(
...     ["/bin/sh", "-c", "ls -l non_existent_file ; exit 0"])
>>> cmd.check_output(stderr=subprocess.STDOUT)
b"ls: ...non_existent_file...: No such file or directory\n"

>>> cmd = SubprocessCommand(["sed", "-e", "s/foo/bar/"])
>>> cmd.check_output(input=b"when in the course of fooman events\n")
b'when in the course of barman events\n'

run(universal_newlines: bool = None, *, capture_output: bool = False, check: bool = False, encoding: str | None = None, errors: str | None = None, input: str | None = None, text: Literal[True]) → CompletedProcess[str] ¶ method[source]

run(universal_newlines: bool = None, *, capture_output: bool = False, check: bool = False, encoding: str, errors: str | None = None, input: str | None = None, text: bool | None = None) → CompletedProcess[str] method

run(universal_newlines: bool = None, *, capture_output: bool = False, check: bool = False, encoding: str | None = None, errors: str, input: str | None = None, text: bool | None = None) → CompletedProcess[str] method

run(*, universal_newlines: Literal[True], capture_output: bool = False, check: bool = False, encoding: str | None = None, errors: str | None = None, input: str | None = None, text: bool | None = None) → CompletedProcess[str] method

run(universal_newlines: Literal[False] = None, *, capture_output: bool = False, check: bool = False, encoding: None = None, errors: None = None, input: bytes | None = None, text: Literal[False] | None = None) → CompletedProcess[bytes] method

Run command in subprocess.run(), optionally overrides via kwargs.

Parameters:

input (t.Union[bytes, str], optional) –
pass string to subprocess’s stdin. Bytes by default, str in text mode.

Text mode is triggered by setting any of text, encoding, errors or universal_newlines.
check (bool) – If True and the exit code was non-zero, it raises a subprocess.CalledProcessError. The CalledProcessError object will have the return code in the returncode attribute, and output & stderr attributes if those streams were captured.
timeout (int) – If given, and the process takes too long, a subprocess.TimeoutExpired
**kwargs (dict, optional) – Overrides existing attributes for subprocess.run()

Examples

>>> import subprocess
>>> cmd = SubprocessCommand(
...     ["/bin/sh", "-c", "ls -l non_existent_file ; exit 0"])
>>> cmd.run()
CompletedProcess(args=['/bin/sh', '-c', 'ls -l non_existent_file ; exit 0'],
                 returncode=0)

>>> import subprocess
>>> cmd = SubprocessCommand(
...     ["/bin/sh", "-c", "ls -l non_existent_file ; exit 0"])
>>> cmd.run(check=True)
CompletedProcess(args=['/bin/sh', '-c', 'ls -l non_existent_file ; exit 0'],
                 returncode=0)

>>> cmd = SubprocessCommand(["sed", "-e", "s/foo/bar/"])
>>> completed = cmd.run(input=b"when in the course of fooman events\n")
>>> completed
CompletedProcess(args=['sed', '-e', 's/foo/bar/'], returncode=0)
>>> completed.stderr

>>> cmd = SubprocessCommand(["sed", "-e", "s/foo/bar/"])
>>> completed = cmd.run(input=b"when in the course of fooman events\n",
...                     capture_output=True)
>>> completed
CompletedProcess(args=['sed', '-e', 's/foo/bar/'], returncode=0,
                stdout=b'when in the course of barman events\n', stderr=b'')
>>> completed.stdout
b'when in the course of barman events\n'
>>> completed.stderr
b''

SubprocessCommand - libvcs._internal.subprocess¶

SubprocessCommand - `libvcs._internal.subprocess`¶