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# Source code for xonsh.aliases

    """Aliases for the xonsh shell."""

    import argparse
    import functools
    import inspect
    import operator
    import os
    import pathlib
    import re
    import shlex
    import shutil
    import sys
    import types
    import typing as tp
    from collections import abc as cabc
    from pathlib import Path
    from typing import Literal

    import xonsh.completers._aliases as xca
    import xonsh.history.main as xhm
    import xonsh.xoreutils.which as xxw
    import xonsh.xoreutils.xcontext as xxt
    from xonsh.built_ins import XSH
    from xonsh.cli_utils import Annotated, Arg, ArgParserAlias
    from xonsh.dirstack import _get_cwd, cd, dirs, popd, pushd
    from xonsh.environ import locate_binary, make_args_env
    from xonsh.foreign_shells import foreign_shell_data
    from xonsh.lib.lazyasd import lazyobject
    from xonsh.parsers.ast import isexpression
    from xonsh.platform import (
        IN_APPIMAGE,
        ON_ANACONDA,
        ON_DARWIN,
        ON_DRAGONFLY,
        ON_FREEBSD,
        ON_NETBSD,
        ON_OPENBSD,
        ON_WINDOWS,
    )
    from xonsh.procs.executables import locate_file
    from xonsh.procs.jobs import bg, clean_jobs, disown, fg, jobs
    from xonsh.procs.specs import DecoratorAlias, SpecAttrDecoratorAlias
    from xonsh.timings import timeit_alias
    from xonsh.tools import (
        ALIAS_KWARG_NAMES,
        XonshError,
        adjust_shlvl,
        argvquote,
        escape_windows_cmd_string,
        print_color,
        print_exception,
        strip_simple_quotes,
        swap_values,
        to_repr_pretty_,
        to_shlvl,
        unthreadable,
    )
    from xonsh.xontribs import xontribs_main

    @lazyobject
    def EXEC_ALIAS_RE():
        return re.compile(r"@\(|\$\(|!\(|\$\[|!\[|\&\&|\|\||\s+and\s+|\s+or\s+|[>|<]")

    class FuncAlias:
        """Provides a callable alias for xonsh commands."""

        attributes_show = ["__xonsh_threadable__", "__xonsh_capturable__", "return_what"]
        attributes_inherit = attributes_show + ["__doc__"]
        return_what: Literal["command", "result"] = "result"

        def __init__(self, name, func=None):
            self.__name__ = self.name = name
            self.func = func
            for attr in self.attributes_inherit:
                if (val := getattr(func, attr, None)) is not None:
                    self.__setattr__(attr, val)

        def __repr__(self):
            r = {"name": self.name, "func": self.func.__name__}
            r |= {
                attr: val
                for attr in self.attributes_show
                if (val := getattr(self, attr, None)) is not None
            }
            return f"FuncAlias({repr(r)})"

        def __call__(
            self,
            args=None,
            stdin=None,
            stdout=None,
            stderr=None,
            spec=None,
            stack=None,
            decorators=None,
        ):
            return run_alias_by_params(
                self.func,
                {
                    "args": args,
                    "stdin": stdin,
                    "stdout": stdout,
                    "stderr": stderr,
                    "spec": spec,
                    "stack": stack,
                    "decorators": decorators,
                },
            )

    class Aliases(cabc.MutableMapping):
        """Represents a location to hold and look up aliases."""

        def __init__(self, *args, **kwargs):
            self._raw = {}
            self.update(*args, **kwargs)

        @staticmethod
        def _get_func_name(func):
            name = func.__name__

            # Strip leading underscore
            if name.startswith("_"):
                name = name[1:]
            return name

        def _register(self, func, name="", dash_case=True):
            name = name or self._get_func_name(func)

            if dash_case:
                name = name.replace("_", "-")

            self[name] = func
            return func

        @tp.overload
        def register(self, func: types.FunctionType) -> types.FunctionType:
            """simple usage"""

        @tp.overload
        def register(
            self, name: str, *, dash_case: bool = True
        ) -> tp.Callable[[types.FunctionType], types.FunctionType]: ...

        def register(self, func_or_name, name=None, dash_case=True):
            """Decorator to register the given function by name."""

            if isinstance(func_or_name, types.FunctionType):
                return self._register(func_or_name, name, dash_case)

            def wrapper(func):
                return self._register(func, func_or_name, dash_case)

            return wrapper

        def return_command(self, f):
            """Decorator that switches alias from returning result to return in new command for execution."""
            f.return_what = "command"
            return f

        def eval_alias(
            self,
            value,
            seen_tokens=frozenset(),
            acc_args=(),
            decorators=None,
        ):
            """
            "Evaluates" the alias ``value``, by recursively looking up the leftmost
            token and "expanding" if it's also an alias.

            A value like ``["cmd", "arg"]`` might transform like this:
            ``> ["cmd", "arg"] -> ["ls", "-al", "arg"] -> callable()``
            where ``cmd=ls -al`` and ``ls`` is an alias with its value being a
            callable.  The resulting callable will be "partially applied" with
            ``["-al", "arg"]``.
            """
            decorators = decorators if decorators is not None else []
            # Beware of mutability: default values for keyword args are evaluated
            # only once.
            if (
                isinstance(value, cabc.Iterable)
                and hasattr(value, "__len__")
                and len(value) > 1
            ):
                i = 0
                for v in value:
                    if isinstance(mod := self._raw.get(str(v)), DecoratorAlias):
                        decorators.append(mod)
                        i += 1
                    else:
                        break
                value = value[i:]

            if callable(value) and getattr(value, "return_what", "result") == "command":
                try:
                    value = value(acc_args, decorators=decorators)
                    acc_args = []
                except Exception as e:
                    print_exception(f"Exception inside alias {value}: {e}")
                    return None
                if not len(value):
                    raise ValueError("return_command alias: zero arguments.")

            if callable(value):
                return [value] + list(acc_args)
            else:
                expand_path = XSH.expand_path
                token, *rest = map(expand_path, value)
                if token in seen_tokens or token not in self._raw:
                    # ^ Making sure things like `egrep=egrep --color=auto` works,
                    # and that `l` evals to `ls --color=auto -CF` if `l=ls -CF`
                    # and `ls=ls --color=auto`
                    rtn = [token]
                    rtn.extend(rest)
                    rtn.extend(acc_args)
                    return rtn
                else:
                    seen_tokens = seen_tokens | {token}
                    acc_args = rest + list(acc_args)
                    return self.eval_alias(
                        self._raw[token],
                        seen_tokens,
                        acc_args,
                        decorators=decorators,
                    )

        def get(
            self,
            key,
            default=None,
            decorators=None,
        ):
            """
            Returns list that represent command with resolved aliases.
            The ``key`` can be string with alias name or list for a command.
            In the first position will be the resolved command name or callable alias.
            If the key is not present, then `default` is returned.

            ``decorators`` is the list of `DecoratorAlias` objects that found during
            resolving aliases (#5443).

            Note! The return value is always list because during resolving
            we can find return_command alias that can completely replace
            command and add new arguments.
            """
            decorators = decorators if decorators is not None else []
            args = []
            if isinstance(key, list):
                args = key[1:]
                key = key[0]
            val = self._raw.get(key)
            if callable(val) and getattr(val, "return_what", "result") == "command":
                try:
                    val = val(args, decorators=decorators)
                    args = []
                except Exception as e:
                    print_exception(f"Exception inside alias {key!r}: {e}")
                    return None
                if not len(val):
                    raise ValueError("return_command alias: zero arguments.")

            if val is None:
                return default
            elif isinstance(val, cabc.Iterable) or callable(val):
                return self.eval_alias(
                    val,
                    seen_tokens={key},
                    decorators=decorators,
                    acc_args=args,
                )
            else:
                msg = "alias of {!r} has an inappropriate type: {!r}"
                raise TypeError(msg.format(key, val))

        def expand_alias(self, line: str, cursor_index: int) -> str:
            """Expands any aliases present in line if alias does not point to a
            builtin function and if alias is only a single command.
            The command won't be expanded if the cursor's inside/behind it.
            """
            word = (line.split(maxsplit=1) or [""])[0]
            if word in self and not callable(self.get(word)[0]):  # type: ignore
                word_idx = line.find(word)
                word_edge = word_idx + len(word)
                if cursor_index > word_edge:
                    # the cursor isn't inside/behind the word
                    expansion = " ".join(self.get(word))
                    line = line[:word_idx] + expansion + line[word_edge:]
            return line

        #
        # Mutable mapping interface
        #

        def __getitem__(self, key):
            return self._raw[key]

        def __setitem__(self, key, val):
            if isinstance(val, str):
                f = "<exec-alias:" + key + ">"
                if EXEC_ALIAS_RE.search(val) is not None:
                    # We have a sub-command (e.g. $(cmd)) or IO redirect (e.g. >>)
                    self._raw[key] = ExecAlias(val, filename=f)
                elif isexpression(val):
                    # expansion substitution
                    lexer = XSH.execer.parser.lexer
                    self._raw[key] = list(map(strip_simple_quotes, lexer.split(val)))
                else:
                    # need to exec alias
                    self._raw[key] = ExecAlias(val, filename=f)
            elif isinstance(val, types.FunctionType):
                self._raw[key] = FuncAlias(key, val)
            else:
                self._raw[key] = val

        def _common_or(self, other):
            new_dict = self._raw.copy()
            for key in dict(other):
                new_dict[key] = other[key]
            return Aliases(new_dict)

        def __or__(self, other):
            return self._common_or(other)

        def __ror__(self, other):
            return self._common_or(other)

        def __ior__(self, other):
            for key in dict(other):
                self[key] = other[key]
            return self

        def __delitem__(self, key):
            del self._raw[key]

        def update(self, *args, **kwargs):
            for key, val in dict(*args, **kwargs).items():
                self[key] = val

        def __iter__(self):
            yield from self._raw

        def __len__(self):
            return len(self._raw)

        def __str__(self):
            return str(self._raw)

        def __repr__(self):
            return f"{self.__class__.__module__}.{self.__class__.__name__}({self._raw})"

        _repr_pretty_ = to_repr_pretty_

    class ExecAlias:
        """Provides an exec alias for xonsh source code."""

        def __init__(self, src, filename="<exec-alias>"):
            """
            Parameters
            ----------
            src : str
                Source code that will be
            """
            self.src = src
            self.filename = filename

        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            execer = XSH.execer
            frame = stack[0][0]  # execute as though we are at the call site

            alias_args = {"args": args}
            for i, a in enumerate(args):
                alias_args[f"arg{i}"] = a

            with XSH.env.swap(alias_args):
                execer.exec(
                    self.src,
                    glbs=frame.f_globals,
                    locs=frame.f_locals,
                    filename=self.filename,
                )
            if XSH.history is not None:
                return XSH.history.last_cmd_rtn

        def __repr__(self):
            return f"ExecAlias({self.src!r}, filename={self.filename!r})"

    class PartialEvalAliasBase:
        """Partially evaluated alias."""

        def __init__(self, f, acc_args=()):
            """
            Parameters
            ----------
            f : callable
                A function to dispatch to.
            acc_args : sequence of strings, optional
                Additional arguments to prepent to the argument list passed in
                when the alias is called.
            """
            self.f = f
            self.acc_args = acc_args
            self.__name__ = getattr(f, "__name__", self.__class__.__name__)

        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout, stderr, spec, stack)

        def __repr__(self):
            return f"{self.__class__.__name__}({self.f!r}, acc_args={self.acc_args!r})"

    class PartialEvalAlias0(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            if args:
                msg = "callable alias {f!r} takes no arguments, but {args!f} provided. "
                msg += "Of these {acc_args!r} were partially applied."
                raise XonshError(msg.format(f=self.f, args=args, acc_args=self.acc_args))
            return self.f()

    class PartialEvalAlias1(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args)

    class PartialEvalAlias2(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin)

    class PartialEvalAlias3(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout)

    class PartialEvalAlias4(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout, stderr)

    class PartialEvalAlias5(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout, stderr, spec)

    class PartialEvalAlias6(PartialEvalAliasBase):
        def __call__(
            self, args, stdin=None, stdout=None, stderr=None, spec=None, stack=None
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout, stderr, spec, stack)

    class PartialEvalAlias7(PartialEvalAliasBase):
        def __call__(
            self,
            args,
            stdin=None,
            stdout=None,
            stderr=None,
            spec=None,
            stack=None,
            decorators=None,
        ):
            args = list(self.acc_args) + args
            return self.f(args, stdin, stdout, stderr, spec, stack, decorators)

    PARTIAL_EVAL_ALIASES = (
        PartialEvalAlias0,
        PartialEvalAlias1,
        PartialEvalAlias2,
        PartialEvalAlias3,
        PartialEvalAlias4,
        PartialEvalAlias5,
        PartialEvalAlias6,
        PartialEvalAlias7,
    )

    def partial_eval_alias(f, acc_args=()):
        """Dispatches the appropriate eval alias based on the number of args to the original callable alias
        and how many arguments to apply.
        """
        # no partial needed if no extra args
        if not acc_args:
            return f
        # need to dispatch
        numargs = 0
        for name, param in inspect.signature(f).parameters.items():
            if (
                param.kind == param.POSITIONAL_ONLY
                or param.kind == param.POSITIONAL_OR_KEYWORD
            ):
                numargs += 1
            elif name in ALIAS_KWARG_NAMES and param.kind == param.KEYWORD_ONLY:
                numargs += 1
        if numargs < 8:
            return PARTIAL_EVAL_ALIASES[numargs](f, acc_args=acc_args)
        else:
            e = "Expected proxy with 7 or fewer arguments for {}, not {}"
            raise XonshError(e.format(", ".join(ALIAS_KWARG_NAMES), numargs))

    def run_alias_by_params(func: tp.Callable, params: dict[str, tp.Any]):
        """
        Run alias function based on signature and params.
        If function param names are in alias signature fill them.
        If function params have unknown names fill using alias signature order.
        """
        alias_params = {
            "args": None,
            "stdin": None,
            "stdout": None,
            "stderr": None,
            "spec": None,
            "stack": None,
            "decorators": None,
        }
        alias_params |= params
        sign = inspect.signature(func)
        func_params = sign.parameters.items()
        kwargs = {
            name: alias_params[name] for name, p in func_params if name in alias_params
        }

        if len(kwargs) != len(func_params):
            # There is unknown param. Switch to positional mode.
            kwargs = dict(
                zip(
                    map(operator.itemgetter(0), func_params),
                    alias_params.values(),
                    strict=False,
                )
            )
        return func(**kwargs)

    #
    # Actual aliases below
    #

    def xonsh_exit(args, stdin=None):
        """Sends signal to exit shell."""
        if not clean_jobs():
            # Do not exit if jobs not cleaned up
            return None, None
        if args:
            try:
                code = int(args[0])
            except ValueError:
                code = 1
        else:
            code = 0
        XSH.exit = code
        print()  # gimme a newline
        return None, None

    def xonsh_reset(args, stdin=None):
        """Clears __xonsh__.ctx"""
        XSH.ctx.clear()

    def source_foreign_fn(
        shell: str,
        files_or_code: Annotated[list[str], Arg(nargs="+")],
        interactive=False,
        login=False,
        envcmd=None,
        aliascmd=None,
        extra_args="",
        safe=True,
        prevcmd="",
        postcmd="",
        funcscmd="",
        sourcer=None,
        use_tmpfile=False,
        seterrprevcmd=None,
        seterrpostcmd=None,
        overwrite_aliases=False,
        suppress_skip_message=False,
        show=False,
        dryrun=False,
        _stderr=None,
    ):
        """Sources a file written in a foreign shell language.

        Parameters
        ----------
        shell
            Name or path to the foreign shell
        files_or_code
            file paths to source or code in the target language.
        interactive : -i, --interactive
            whether the sourced shell should be interactive
        login : -l, --login
            whether the sourced shell should be login
        envcmd : --envcmd
            command to print environment
        aliascmd : --aliascmd
            command to print aliases
        extra_args : --extra-args
            extra arguments needed to run the shell
        safe : -u, --unsafe
            whether the source shell should be run safely, and not raise any errors, even if they occur.
        prevcmd : -p, --prevcmd
            command(s) to run before any other commands, replaces traditional source.
        postcmd : --postcmd
            command(s) to run after all other commands
        funcscmd : --funcscmd
            code to find locations of all native functions in the shell language.
        sourcer : --sourcer
            the source command in the target shell language.
            If this is not set, a default value will attempt to be
            looked up based on the shell name.
        use_tmpfile : --use-tmpfile
            whether the commands for source shell should be written to a temporary file.
        seterrprevcmd : --seterrprevcmd
            command(s) to set exit-on-error before any other commands.
        seterrpostcmd : --seterrpostcmd
            command(s) to set exit-on-error after all other commands.
        overwrite_aliases : --overwrite-aliases
            flag for whether or not sourced aliases should replace the current xonsh aliases.
        suppress_skip_message : --suppress-skip-message
            flag for whether or not skip messages should be suppressed.
        show : --show
            show the script output.
        dryrun : -d, --dry-run
            Will not actually source the file.
        """
        extra_args = tuple(extra_args.split())
        env = XSH.env
        suppress_skip_message = (
            env.get("FOREIGN_ALIASES_SUPPRESS_SKIP_MESSAGE")
            if not suppress_skip_message
            else suppress_skip_message
        )
        files: tuple[str, ...] = ()
        if prevcmd:
            pass  # don't change prevcmd if given explicitly
        elif os.path.isfile(files_or_code[0]):
            if not sourcer:
                return (None, "xonsh: error: `sourcer` command is not mentioned.\n", 1)
            # we have filenames to source
            shell_name = os.path.basename(shell).lower()
            quote = (
                functools.partial(argvquote, force=True)
                if shell_name in {"cmd", "cmd.exe"}
                else shlex.quote
            )
            prevcmd = "".join(f"{sourcer} {quote(f)}\n" for f in files_or_code)
            files = tuple(files_or_code)
        elif not prevcmd:
            prevcmd = " ".join(files_or_code)  # code to run, no files
        foreign_shell_data.cache_clear()  # make sure that we don't get prev src
        fsenv, fsaliases = foreign_shell_data(
            shell=shell,
            login=login,
            interactive=interactive,
            envcmd=envcmd,
            aliascmd=aliascmd,
            extra_args=extra_args,
            safe=safe,
            prevcmd=prevcmd,
            postcmd=postcmd,
            funcscmd=funcscmd or None,  # the default is None in the called function
            sourcer=sourcer,
            use_tmpfile=use_tmpfile,
            seterrprevcmd=seterrprevcmd,
            seterrpostcmd=seterrpostcmd,
            show=show,
            dryrun=dryrun,
            files=files,
        )
        if fsenv is None:
            if dryrun:
                return
            else:
                msg = f"xonsh: error: Source failed: {prevcmd!r}\n"
                msg += "xonsh: error: Possible reasons: File not found or syntax error\n"
                return (None, msg, 1)
        # apply results
        denv = env.detype()
        for k, v in fsenv.items():
            if k == "SHLVL":  # ignore $SHLVL as sourcing should not change $SHLVL
                continue
            if k in denv and v == denv[k]:
                continue  # no change from original
            env[k] = v
        # Remove any env-vars that were unset by the script.
        for k in denv:
            if k not in fsenv:
                env.pop(k, None)
        # Update aliases
        baliases = XSH.aliases
        for k, v in fsaliases.items():
            if k in baliases and v == baliases[k]:
                continue  # no change from original
            elif overwrite_aliases or k not in baliases:
                baliases[k] = v
            elif suppress_skip_message:
                pass
            else:
                msg = (
                    "Skipping application of {0!r} alias from {1!r} "
                    "since it shares a name with an existing xonsh alias. "
                    'Use "--overwrite-alias" option to apply it anyway. '
                    'You may prevent this message with "--suppress-skip-message" or '
                    '"$FOREIGN_ALIASES_SUPPRESS_SKIP_MESSAGE = True".'
                )
                print(msg.format(k, shell), file=_stderr)

    class SourceForeignAlias(ArgParserAlias):

        def build(self):
            parser = self.create_parser(**self.kwargs)
            # for backwards compatibility
            parser.add_argument(
                "-n",
                "--non-interactive",
                action="store_false",
                dest="interactive",
                help="Deprecated: The default mode runs in non-interactive mode.",
            )
            return parser

    source_foreign = SourceForeignAlias(
        func=source_foreign_fn, has_args=True, prog="source-foreign"
    )

    def source_alias_fn(
        files: Annotated[list[str], Arg(nargs="+")], ignore_ext=False, _stdin=None
    ):
        """Executes the contents of the provided files in the current context.
        If sourced file isn't found in cwd, search for file along $PATH to source
        instead.

        Parameters
        ----------
        files
            paths to source files.
        ignore_ext : -e, --ignore-ext
            don't check the file extension
        """
        env = XSH.env
        encoding = env.get("XONSH_ENCODING")
        errors = env.get("XONSH_ENCODING_ERRORS")
        for i, fname in enumerate(files):
            fpath = fname
            if not os.path.isfile(fpath):
                fpath = locate_file(fname)
                if fpath is None:
                    if env.get("XONSH_DEBUG"):
                        print(f"source: {fname}: No such file", file=sys.stderr)
                    if i == 0:
                        raise RuntimeError(
                            "must source at least one file, " + fname + " does not exist."
                        )
                    break
            _, fext = os.path.splitext(fpath)
            fext, name = Path(fpath).suffix, Path(fpath).name
            if not fext and name.startswith("."):
                fext = name  # hidden file with no extension
            if not ignore_ext and fext not in {".xsh", ".py", ".xonshrc"}:
                raise RuntimeError(
                    f"attempting to source file with non-xonsh extension {repr(name)}! "
                    f"If you are trying to source a file in another language, "
                    "then please use the appropriate source command "
                    "e.g. `source-bash script.sh`. "
                    "Use `-e` to ignore extension checking and source the file."
                )
            with open(fpath, encoding=encoding, errors=errors) as fp:
                src = fp.read()
            if not src.endswith("\n"):
                src += "\n"
            ctx = XSH.ctx
            updates = {"__file__": fpath, "__name__": os.path.abspath(fpath)}
            with (
                env.swap(XONSH_MODE="source", **make_args_env(files[i + 1 :])),
                swap_values(ctx, updates),
            ):
                try:
                    XSH.builtins.execx(src, "exec", ctx, filename=fpath)
                except Exception:
                    print_color(
                        "{RED}You may be attempting to source non-xonsh file! "
                        "{RESET}If you are trying to source a file in "
                        "another language, then please use the appropriate "
                        "source command. For example, {GREEN}`source-bash "
                        "script.sh`{RESET}",
                        file=sys.stderr,
                    )
                    raise

    source_alias = ArgParserAlias(
        func=source_alias_fn, has_args=True, prog="source", threadable=False
    )

    def source_cmd_fn(
        files: Annotated[list[str], Arg(nargs="+")],
        login=False,
        aliascmd=None,
        extra_args="",
        safe=True,
        postcmd="",
        funcscmd="",
        seterrprevcmd=None,
        overwrite_aliases=False,
        suppress_skip_message=False,
        show=False,
        dryrun=False,
        _stderr=None,
    ):
        """
            Source cmd.exe files

        Parameters
        ----------
        files
            paths to source files.
        login : -l, --login
            whether the sourced shell should be login
        envcmd : --envcmd
            command to print environment
        aliascmd : --aliascmd
            command to print aliases
        extra_args : --extra-args
            extra arguments needed to run the shell
        safe : -s, --safe
            whether the source shell should be run safely, and not raise any errors, even if they occur.
        postcmd : --postcmd
            command(s) to run after all other commands
        funcscmd : --funcscmd
            code to find locations of all native functions in the shell language.
        seterrprevcmd : --seterrprevcmd
            command(s) to set exit-on-error before any other commands.
        overwrite_aliases : --overwrite-aliases
            flag for whether or not sourced aliases should replace the current xonsh aliases.
        suppress_skip_message : --suppress-skip-message
            flag for whether or not skip messages should be suppressed.
        show : --show
            show the script output.
        dryrun : -d, --dry-run
            Will not actually source the file.
        """
        args = list(files)
        fpath = locate_binary(args[0])
        args[0] = fpath if fpath else args[0]
        if not os.path.isfile(args[0]):
            return (None, f"xonsh: error: File not found: {args[0]}\n", 1)
        prevcmd = "call "
        prevcmd += " ".join([argvquote(arg, force=True) for arg in args])
        prevcmd = escape_windows_cmd_string(prevcmd)
        with XSH.env.swap(PROMPT="$P$G"):
            return source_foreign_fn(
                shell="cmd",
                files_or_code=args,
                interactive=True,
                sourcer="call",
                envcmd="set",
                seterrpostcmd="if errorlevel 1 exit 1",
                use_tmpfile=True,
                prevcmd=prevcmd,
                #     from this function
                login=login,
                aliascmd=aliascmd,
                extra_args=extra_args,
                safe=safe,
                postcmd=postcmd,
                funcscmd=funcscmd,
                seterrprevcmd=seterrprevcmd,
                overwrite_aliases=overwrite_aliases,
                suppress_skip_message=suppress_skip_message,
                show=show,
                dryrun=dryrun,
            )

    source_cmd = ArgParserAlias(func=source_cmd_fn, has_args=True, prog="source-cmd")

    def xexec_fn(
        command: Annotated[list[str], Arg(nargs=argparse.REMAINDER)],
        login=False,
        clean=False,
        name="",
        _stdin=None,
    ):
        """exec (also aliased as xexec) uses the os.execvpe() function to
        replace the xonsh process with the specified program.

        This provides the functionality of the bash 'exec' builtin::

            >>> exec bash -l -i
            bash $

        Parameters
        ----------
        command
            program to launch along its arguments
        login : -l, --login
            the shell places a dash at the
            beginning of the zeroth argument passed to command to simulate login
            shell.
        clean : -c, --clean
            causes command to be executed with an empty environment.
        name : -a, --name
            the shell passes name as the zeroth argument
            to the executed command.

        Notes
        -----
        This command **is not** the same as the Python builtin function
        exec(). That function is for running Python code. This command,
        which shares the same name as the sh-lang statement, is for launching
        a command directly in the same process. In the event of a name conflict,
        please use the xexec command directly or dive into subprocess mode
        explicitly with ![exec command]. For more details, please see
        http://xon.sh/faq.html#exec.
        """
        if len(command) == 0:
            return (None, "xonsh: exec: no command specified\n", 1)

        cmd = command[0]
        if name:
            command[0] = name
        if login:
            command[0] = f"-{command[0]}"

        denv = {}
        if not clean:
            denv = XSH.env.detype()

            # decrement $SHLVL to mirror bash's behaviour
            if "SHLVL" in denv:
                old_shlvl = to_shlvl(denv["SHLVL"])
                denv["SHLVL"] = str(adjust_shlvl(old_shlvl, -1))

        try:
            os.execvpe(cmd, command, denv)
        except FileNotFoundError as e:
            return (
                None,
                f"xonsh: exec: file not found: {e.args[1]}: {command[0]}\n",
                1,
            )

    xexec = ArgParserAlias(func=xexec_fn, has_args=True, prog="xexec")

    @lazyobject
    def xonfig():
        """Runs the xonsh configuration utility."""
        from xonsh.xonfig import xonfig_main  # lazy import

        return xonfig_main

    @unthreadable
    def trace(args, stdin=None, stdout=None, stderr=None, spec=None):
        """Runs the xonsh tracer utility."""
        from xonsh.tracer import tracermain  # lazy import

        try:
            return tracermain(args, stdin=stdin, stdout=stdout, stderr=stderr, spec=spec)
        except SystemExit:
            pass

    def showcmd(args, stdin=None):
        """usage: showcmd [-e|--expand-alias] [-h|--help] cmd

        Displays the command and arguments as a list of strings that xonsh would
        run in subprocess mode. This is useful for determining how xonsh evaluates
        your commands and arguments prior to running these commands.

        optional arguments:
          -e, --expand-alias    expand alias
          -h, --help            show this help message and exit

        Examples
        --------
          @ showcmd echo $USER "can't" hear "the sea"
          ['echo', 'I', "can't", 'hear', 'the sea']

          @ aliases['ali'] = 'echo 1'
          @ showcmd -e ali 2
          ['echo', '1', '2']

        """
        if len(args) == 0 or (len(args) == 1 and args[0] in {"-h", "--help"}):
            print(showcmd.__doc__.rstrip().replace("\n    ", "\n"))
        elif args[0] in {"-e", "--expand-alias"}:
            sys.displayhook(XSH.aliases.eval_alias(args[1:]))
        else:
            sys.displayhook(args)

    def detect_xpip_alias():
        """
        Determines the correct invocation to get xonsh's pip
        """
        if not getattr(sys, "executable", None):
            return lambda args, stdin=None: (
                "",
                "Sorry, unable to run pip on your system (missing sys.executable)",
                1,
            )

        basecmd = [sys.executable, "-m", "pip"]
        try:
            if ON_WINDOWS:
                # XXX: Does windows have an installation mode that requires UAC?
                return basecmd
            elif IN_APPIMAGE:
                # In AppImage `sys.executable` is equal to path to xonsh.AppImage file and the real python executable is in $_
                return [
                    XSH.env.get("_", "APPIMAGE_PYTHON_EXECUTABLE_NOT_FOUND"),
                    "-m",
                    "pip",
                ]
            elif not os.access(os.path.dirname(sys.executable), os.W_OK):
                return (
                    sys.executable
                    + " -m pip @(['install', '--user'] + $args[1:] if $args and $args[0] == 'install' else $args)"
                )
            else:
                return basecmd
        except Exception:
            # Something freaky happened, return something that'll probably work
            return basecmd

    def _find_cmd_exe() -> str:
        """
        Resolve the cmd.exe executable.

        Avoids using COMSPEC in order to allow COMSPEC to be used to
        indicate Xonsh (or other shell) as the default shell. (#5701)
        """
        canonical = pathlib.Path(os.environ["SystemRoot"], "System32", "cmd.exe")
        return str(canonical) if canonical.is_file() else os.environ["COMSPEC"]

    def make_default_aliases():
        """Creates a new default aliases dictionary."""
        default_aliases = {
            "cd": cd,
            "pushd": pushd,
            "popd": popd,
            "dirs": dirs,
            "jobs": jobs,
            "fg": fg,
            "bg": bg,
            "disown": disown,
            "EOF": xonsh_exit,
            "exit": xonsh_exit,
            "quit": xonsh_exit,
            "exec": xexec,
            "xexec": xexec,
            "source": source_alias,
            "source-zsh": SourceForeignAlias(
                func=functools.partial(source_foreign_fn, "zsh", sourcer="source"),
                has_args=True,
                prog="source-zsh",
            ),
            "source-bash": SourceForeignAlias(
                func=functools.partial(source_foreign_fn, "bash", sourcer="source"),
                has_args=True,
                prog="source-bash",
            ),
            "source-cmd": source_cmd,
            "source-foreign": source_foreign,
            "history": xhm.history_main,
            "trace": trace,
            "timeit": timeit_alias,
            "xonfig": xonfig,
            "showcmd": showcmd,
            "which": xxw.which,
            "xcontext": xxt.xcontext,
            "xontrib": xontribs_main,
            "completer": xca.completer_alias,
            "xpip": detect_xpip_alias(),
            "xpython": [XSH.env.get("_", sys.executable)]
            if IN_APPIMAGE
            else [sys.executable],
            "xreset": xonsh_reset,
            "@thread": SpecAttrDecoratorAlias(
                {"threadable": True, "force_threadable": True},
                "Mark current command as threadable.",
            ),
            "@unthread": SpecAttrDecoratorAlias(
                {"threadable": False, "force_threadable": False},
                "Mark current command as unthreadable.",
            ),
        }
        if ON_WINDOWS:
            # Borrow builtin commands from cmd.exe.
            windows_cmd_aliases = {
                "cls",
                "copy",
                "del",
                "dir",
                "echo",
                "erase",
                "md",
                "mkdir",
                "mklink",
                "move",
                "rd",
                "ren",
                "rename",
                "rmdir",
                "time",
                "type",
                "vol",
            }
            for alias in windows_cmd_aliases:
                default_aliases[alias] = [_find_cmd_exe(), "/c", alias]
            default_aliases["call"] = ["source-cmd"]
            default_aliases["source-bat"] = ["source-cmd"]
            default_aliases["clear"] = "cls"
            if ON_ANACONDA:
                # Add aliases specific to the Anaconda python distribution.
                default_aliases["activate"] = ["source-cmd", "activate.bat"]
                default_aliases["deactivate"] = ["source-cmd", "deactivate.bat"]
            if shutil.which("sudo", path=XSH.env.get_detyped("PATH")):
                # XSH.commands_cache is not available during setup
                import xonsh.platforms.winutils as winutils

                def sudo(args):
                    if len(args) < 1:
                        print("You need to provide an executable to run as Administrator.")
                        return
                    cmd = args[0]
                    if locate_binary(cmd):
                        return winutils.sudo(cmd, args[1:])
                    elif cmd.lower() in windows_cmd_aliases:
                        args = ["/D", "/C", "CD", _get_cwd(), "&&"] + args
                        return winutils.sudo("cmd", args)
                    else:
                        msg = 'Cannot find the path for executable "{0}".'
                        print(msg.format(cmd))

                default_aliases["sudo"] = sudo
        elif ON_DARWIN:
            default_aliases["ls"] = ["ls", "-G"]
        elif ON_FREEBSD or ON_DRAGONFLY:
            default_aliases["grep"] = ["grep", "--color=auto"]
            default_aliases["egrep"] = ["egrep", "--color=auto"]
            default_aliases["fgrep"] = ["fgrep", "--color=auto"]
            default_aliases["ls"] = ["ls", "-G"]
        elif ON_NETBSD:
            default_aliases["grep"] = ["grep", "--color=auto"]
            default_aliases["egrep"] = ["egrep", "--color=auto"]
            default_aliases["fgrep"] = ["fgrep", "--color=auto"]
        elif ON_OPENBSD:
            pass
        else:
            default_aliases["grep"] = ["grep", "--color=auto"]
            default_aliases["egrep"] = ["egrep", "--color=auto"]
            default_aliases["fgrep"] = ["fgrep", "--color=auto"]
            default_aliases["ls"] = ["ls", "--color=auto", "-v"]
        return default_aliases