Source code for xonsh.built_ins

# -*- coding: utf-8 -*-
"""The xonsh built-ins.

Note that this module is named 'built_ins' so as not to be confused with the
special Python builtins module.
"""
import io
import os
import re
import sys
import types
import shlex
import signal
import atexit
import pathlib
import inspect
import builtins
import itertools
import subprocess
import contextlib
import collections.abc as cabc

from xonsh.ast import AST
from xonsh.lazyasd import LazyObject, lazyobject
from xonsh.inspectors import Inspector
from xonsh.aliases import Aliases, make_default_aliases
from xonsh.environ import Env, default_env, locate_binary
from xonsh.jobs import add_job
from xonsh.platform import ON_POSIX, ON_WINDOWS
from xonsh.proc import (
    PopenThread, ProcProxyThread, ProcProxy, ConsoleParallelReader,
    pause_call_resume, CommandPipeline, HiddenCommandPipeline,
    STDOUT_CAPTURE_KINDS)
from xonsh.tools import (
    suggest_commands, expand_path, globpath, XonshError,
    XonshCalledProcessError
)
from xonsh.lazyimps import pty, termios
from xonsh.commands_cache import CommandsCache
from xonsh.events import events

import xonsh.completers.init

BUILTINS_LOADED = False
INSPECTOR = LazyObject(Inspector, globals(), 'INSPECTOR')


@lazyobject
def AT_EXIT_SIGNALS():
    sigs = (signal.SIGABRT, signal.SIGFPE, signal.SIGILL, signal.SIGSEGV,
            signal.SIGTERM)
    if ON_POSIX:
        sigs += (signal.SIGTSTP, signal.SIGQUIT, signal.SIGHUP)
    return sigs


[docs]def resetting_signal_handle(sig, f): """Sets a new signal handle that will automatically restore the old value once the new handle is finished. """ oldh = signal.getsignal(sig) def newh(s=None, frame=None): f(s, frame) signal.signal(sig, oldh) if sig != 0: sys.exit(sig) signal.signal(sig, newh)
[docs]def helper(x, name=''): """Prints help about, and then returns that variable.""" INSPECTOR.pinfo(x, oname=name, detail_level=0) return x
[docs]def superhelper(x, name=''): """Prints help about, and then returns that variable.""" INSPECTOR.pinfo(x, oname=name, detail_level=1) return x
[docs]def reglob(path, parts=None, i=None): """Regular expression-based globbing.""" if parts is None: path = os.path.normpath(path) drive, tail = os.path.splitdrive(path) parts = tail.split(os.sep) d = os.sep if os.path.isabs(path) else '.' d = os.path.join(drive, d) return reglob(d, parts, i=0) base = subdir = path if i == 0: if not os.path.isabs(base): base = '' elif len(parts) > 1: i += 1 regex = os.path.join(base, parts[i]) if ON_WINDOWS: # currently unable to access regex backslash sequences # on Windows due to paths using \. regex = regex.replace('\\', '\\\\') regex = re.compile(regex) files = os.listdir(subdir) files.sort() paths = [] i1 = i + 1 if i1 == len(parts): for f in files: p = os.path.join(base, f) if regex.fullmatch(p) is not None: paths.append(p) else: for f in files: p = os.path.join(base, f) if regex.fullmatch(p) is None or not os.path.isdir(p): continue paths += reglob(p, parts=parts, i=i1) return paths
[docs]def path_literal(s): s = expand_path(s) return pathlib.Path(s)
[docs]def regexsearch(s): s = expand_path(s) return reglob(s)
[docs]def globsearch(s): csc = builtins.__xonsh_env__.get('CASE_SENSITIVE_COMPLETIONS') glob_sorted = builtins.__xonsh_env__.get('GLOB_SORTED') return globpath(s, ignore_case=(not csc), return_empty=True, sort_result=glob_sorted)
[docs]def pathsearch(func, s, pymode=False, pathobj=False): """ Takes a string and returns a list of file paths that match (regex, glob, or arbitrary search function). If pathobj=True, the return is a list of pathlib.Path objects instead of strings. """ if (not callable(func) or len(inspect.signature(func).parameters) != 1): error = "%r is not a known path search function" raise XonshError(error % func) o = func(s) if pathobj and pymode: o = list(map(pathlib.Path, o)) no_match = [] if pymode else [s] return o if len(o) != 0 else no_match
RE_SHEBANG = LazyObject(lambda: re.compile(r'#![ \t]*(.+?)$'), globals(), 'RE_SHEBANG') def _is_binary(fname, limit=80): with open(fname, 'rb') as f: for i in range(limit): char = f.read(1) if char == b'\0': return True if char == b'\n': return False if char == b'': return False return False def _un_shebang(x): if x == '/usr/bin/env': return [] elif any(x.startswith(i) for i in ['/usr/bin', '/usr/local/bin', '/bin']): x = os.path.basename(x) elif x.endswith('python') or x.endswith('python.exe'): x = 'python' if x == 'xonsh': return ['python', '-m', 'xonsh.main'] return [x]
[docs]def get_script_subproc_command(fname, args): """Given the name of a script outside the path, returns a list representing an appropriate subprocess command to execute the script. Raises PermissionError if the script is not executable. """ # make sure file is executable if not os.access(fname, os.X_OK): raise PermissionError if ON_POSIX and not os.access(fname, os.R_OK): # on some systems, some importnat programs (e.g. sudo) will have # execute permissions but not read/write permisions. This enables # things with the SUID set to be run. Needs to come before _is_binary() # is called, because that function tries to read the file. return [fname] + args elif _is_binary(fname): # if the file is a binary, we should call it directly return [fname] + args if ON_WINDOWS: # Windows can execute various filetypes directly # as given in PATHEXT _, ext = os.path.splitext(fname) if ext.upper() in builtins.__xonsh_env__.get('PATHEXT'): return [fname] + args # find interpreter with open(fname, 'rb') as f: first_line = f.readline().decode().strip() m = RE_SHEBANG.match(first_line) # xonsh is the default interpreter if m is None: interp = ['xonsh'] else: interp = m.group(1).strip() if len(interp) > 0: interp = shlex.split(interp) else: interp = ['xonsh'] if ON_WINDOWS: o = [] for i in interp: o.extend(_un_shebang(i)) interp = o return interp + [fname] + args
@lazyobject def _REDIR_REGEX(): name = "(o(?:ut)?|e(?:rr)?|a(?:ll)?|&?\d?)" return re.compile("{r}(>?>|<){r}$".format(r=name)) _MODES = LazyObject(lambda: {'>>': 'a', '>': 'w', '<': 'r'}, globals(), '_MODES') _WRITE_MODES = LazyObject(lambda: frozenset({'w', 'a'}), globals(), '_WRITE_MODES') _REDIR_ALL = LazyObject(lambda: frozenset({'&', 'a', 'all'}), globals(), '_REDIR_ALL') _REDIR_ERR = LazyObject(lambda: frozenset({'2', 'e', 'err'}), globals(), '_REDIR_ERR') _REDIR_OUT = LazyObject(lambda: frozenset({'', '1', 'o', 'out'}), globals(), '_REDIR_OUT') _E2O_MAP = LazyObject(lambda: frozenset({'{}>{}'.format(e, o) for e in _REDIR_ERR for o in _REDIR_OUT if o != ''}), globals(), '_E2O_MAP') _O2E_MAP = LazyObject(lambda: frozenset({'{}>{}'.format(o, e) for e in _REDIR_ERR for o in _REDIR_OUT if o != ''}), globals(), '_O2E_MAP') def _is_redirect(x): return isinstance(x, str) and _REDIR_REGEX.match(x)
[docs]def safe_open(fname, mode, buffering=-1): """Safely attempts to open a file in for xonsh subprocs.""" # file descriptors try: return io.open(fname, mode, buffering=buffering) except PermissionError: raise XonshError('xonsh: {0}: permission denied'.format(fname)) except FileNotFoundError: raise XonshError('xonsh: {0}: no such file or directory'.format(fname)) except Exception: raise XonshError('xonsh: {0}: unable to open file'.format(fname))
[docs]def safe_close(x): """Safely attempts to close an object.""" if not isinstance(x, io.IOBase): return if x.closed: return try: x.close() except Exception: pass
def _parse_redirects(r, loc=None): """returns origin, mode, destination tuple""" orig, mode, dest = _REDIR_REGEX.match(r).groups() # redirect to fd if dest.startswith('&'): try: dest = int(dest[1:]) if loc is None: loc, dest = dest, '' # NOQA else: e = 'Unrecognized redirection command: {}'.format(r) raise XonshError(e) except (ValueError, XonshError): raise except Exception: pass mode = _MODES.get(mode, None) if mode == 'r' and (len(orig) > 0 or len(dest) > 0): raise XonshError('Unrecognized redirection command: {}'.format(r)) elif mode in _WRITE_MODES and len(dest) > 0: raise XonshError('Unrecognized redirection command: {}'.format(r)) return orig, mode, dest def _redirect_streams(r, loc=None): """Returns stdin, stdout, stderr tuple of redirections.""" stdin = stdout = stderr = None no_ampersand = r.replace('&', '') # special case of redirecting stderr to stdout if no_ampersand in _E2O_MAP: stderr = subprocess.STDOUT return stdin, stdout, stderr elif no_ampersand in _O2E_MAP: stdout = 2 # using 2 as a flag, rather than using a file object return stdin, stdout, stderr # get streams orig, mode, dest = _parse_redirects(r) if mode == 'r': stdin = safe_open(loc, mode) elif mode in _WRITE_MODES: if orig in _REDIR_ALL: stdout = stderr = safe_open(loc, mode) elif orig in _REDIR_OUT: stdout = safe_open(loc, mode) elif orig in _REDIR_ERR: stderr = safe_open(loc, mode) else: raise XonshError('Unrecognized redirection command: {}'.format(r)) else: raise XonshError('Unrecognized redirection command: {}'.format(r)) return stdin, stdout, stderr
[docs]def default_signal_pauser(n, f): """Pauses a signal, as needed.""" signal.pause()
[docs]def no_pg_xonsh_preexec_fn(): """Default subprocess preexec function for when there is no existing pipeline group. """ os.setpgrp() signal.signal(signal.SIGTSTP, default_signal_pauser)
[docs]class SubprocSpec: """A container for specifiying how a subprocess command should be executed. """ kwnames = ('stdin', 'stdout', 'stderr', 'universal_newlines') def __init__(self, cmd, *, cls=subprocess.Popen, stdin=None, stdout=None, stderr=None, universal_newlines=False, captured=False): """ Parameters ---------- cmd : list of str Command to be run. cls : Popen-like Class to run the subprocess with. stdin : file-like Popen file descriptor or flag for stdin. stdout : file-like Popen file descriptor or flag for stdout. stderr : file-like Popen file descriptor or flag for stderr. universal_newlines : bool Whether or not to use universal newlines. captured : bool or str, optional The flag for if the subprocess is captured, may be one of: False for $[], 'stdout' for $(), 'hiddenobject' for ![], or 'object' for !(). Attributes ---------- args : list of str Arguments as originally supplied. alias : list of str, callable, or None The alias that was reolved for this command, if any. binary_loc : str or None Path to binary to execute. is_proxy : bool Whether or not the subprocess is or should be run as a proxy. background : bool Whether or not the subprocess should be started in the background. threadable : bool Whether or not the subprocess is able to be run in a background thread, rather than the main thread. last_in_pipeline : bool Whether the subprocess is the last in the execution pipeline. captured_stdout : file-like Handle to captured stdin captured_stderr : file-like Handle to captured stderr """ self._stdin = self._stdout = self._stderr = None # args self.cmd = list(cmd) self.cls = cls self.stdin = stdin self.stdout = stdout self.stderr = stderr self.universal_newlines = universal_newlines self.captured = captured # pure attrs self.args = list(cmd) self.alias = None self.binary_loc = None self.is_proxy = False self.background = False self.threadable = True self.last_in_pipeline = False self.captured_stdout = None self.captured_stderr = None def __str__(self): s = self.__class__.__name__ + '(' + str(self.cmd) + ', ' s += self.cls.__name__ + ', ' kws = [n + '=' + str(getattr(self, n)) for n in self.kwnames] s += ', '.join(kws) + ')' return s def __repr__(self): s = self.__class__.__name__ + '(' + repr(self.cmd) + ', ' s += self.cls.__name__ + ', ' kws = [n + '=' + repr(getattr(self, n)) for n in self.kwnames] s += ', '.join(kws) + ')' return s # # Properties # @property def stdin(self): return self._stdin @stdin.setter def stdin(self, value): if self._stdin is None: self._stdin = value elif value is None: pass else: safe_close(value) msg = 'Multiple inputs for stdin for {0!r}' msg = msg.format(' '.join(self.args)) raise XonshError(msg) @property def stdout(self): return self._stdout @stdout.setter def stdout(self, value): if self._stdout is None: self._stdout = value elif value is None: pass else: safe_close(value) msg = 'Multiple redirections for stdout for {0!r}' msg = msg.format(' '.join(self.args)) raise XonshError(msg) @property def stderr(self): return self._stderr @stderr.setter def stderr(self, value): if self._stderr is None: self._stderr = value elif value is None: pass else: safe_close(value) msg = 'Multiple redirections for stderr for {0!r}' msg = msg.format(' '.join(self.args)) raise XonshError(msg) # # Execution methods #
[docs] def run(self, *, pipeline_group=None): """Launches the subprocess and returns the object.""" kwargs = {n: getattr(self, n) for n in self.kwnames} self.prep_env(kwargs) self.prep_preexec_fn(kwargs, pipeline_group=pipeline_group) if callable(self.alias): if 'preexec_fn' in kwargs: kwargs.pop('preexec_fn') p = self.cls(self.alias, self.cmd, **kwargs) else: self._fix_null_cmd_bytes() p = self._run_binary(kwargs) p.spec = self p.last_in_pipeline = self.last_in_pipeline p.captured_stdout = self.captured_stdout p.captured_stderr = self.captured_stderr return p
def _run_binary(self, kwargs): try: bufsize = 1 p = self.cls(self.cmd, bufsize=bufsize, **kwargs) except PermissionError: e = 'xonsh: subprocess mode: permission denied: {0}' raise XonshError(e.format(self.cmd[0])) except FileNotFoundError: cmd0 = self.cmd[0] e = 'xonsh: subprocess mode: command not found: {0}'.format(cmd0) env = builtins.__xonsh_env__ sug = suggest_commands(cmd0, env, builtins.aliases) if len(sug.strip()) > 0: e += '\n' + suggest_commands(cmd0, env, builtins.aliases) raise XonshError(e) return p
[docs] def prep_env(self, kwargs): """Prepares the environment to use in the subprocess.""" denv = builtins.__xonsh_env__.detype() if ON_WINDOWS: # Over write prompt variable as xonsh's $PROMPT does # not make much sense for other subprocs denv['PROMPT'] = '$P$G' kwargs['env'] = denv
[docs] def prep_preexec_fn(self, kwargs, pipeline_group=None): """Prepares the 'preexec_fn' keyword argument""" if not ON_POSIX: return if not builtins.__xonsh_env__.get('XONSH_INTERACTIVE'): return if pipeline_group is None: xonsh_preexec_fn = no_pg_xonsh_preexec_fn else: def xonsh_preexec_fn(): """Preexec function bound to a pipeline group.""" os.setpgid(0, pipeline_group) signal.signal(signal.SIGTSTP, default_signal_pauser) kwargs['preexec_fn'] = xonsh_preexec_fn
def _fix_null_cmd_bytes(self): # Popen does not accept null bytes in its input commands. # that doesn;t stop some subproces from using them. Here we # escape them just in case. cmd = self.cmd for i in range(len(cmd)): cmd[i] = cmd[i].replace('\0', '\\0') # # Building methods # @classmethod
[docs] def build(kls, cmd, *, cls=subprocess.Popen, **kwargs): """Creates an instance of the subprocess command, with any modifcations and adjustments based on the actual cmd that was recieved. """ # modifications that do not alter cmds may come before creating instance spec = kls(cmd, cls=cls, **kwargs) # modifications that alter cmds must come after creating instance # perform initial redirects spec.redirect_leading() spec.redirect_trailing() # apply aliases spec.resolve_alias() spec.resolve_binary_loc() spec.resolve_auto_cd() spec.resolve_executable_commands() spec.resolve_alias_cls() return spec
[docs] def redirect_leading(self): """Manage leading redirects such as with '< input.txt COMMAND'. """ while len(self.cmd) >= 3 and self.cmd[0] == '<': self.stdin = safe_open(self.cmd[1], 'r') self.cmd = self.cmd[2:]
[docs] def redirect_trailing(self): """Manages trailing redirects.""" while True: cmd = self.cmd if len(cmd) >= 3 and _is_redirect(cmd[-2]): streams = _redirect_streams(cmd[-2], cmd[-1]) self.stdin, self.stdout, self.stderr = streams self.cmd = cmd[:-2] elif len(cmd) >= 2 and _is_redirect(cmd[-1]): streams = _redirect_streams(cmd[-1]) self.stdin, self.stdout, self.stderr = streams self.cmd = cmd[:-1] else: break
[docs] def resolve_alias(self): """Sets alias in command, if applicable.""" cmd0 = self.cmd[0] if callable(cmd0): alias = cmd0 else: alias = builtins.aliases.get(cmd0, None) self.alias = alias
[docs] def resolve_binary_loc(self): """Sets the binary location""" alias = self.alias if alias is None: binary_loc = locate_binary(self.cmd[0]) elif callable(alias): binary_loc = None else: binary_loc = locate_binary(alias[0]) self.binary_loc = binary_loc
[docs] def resolve_auto_cd(self): """Implements AUTO_CD functionality.""" if not (self.alias is None and self.binary_loc is None and len(self.cmd) == 1 and builtins.__xonsh_env__.get('AUTO_CD') and os.path.isdir(self.cmd[0])): return self.cmd.insert(0, 'cd') self.alias = builtins.aliases.get('cd', None)
[docs] def resolve_executable_commands(self): """Resolve command executables, if applicable.""" alias = self.alias if alias is None: pass elif callable(alias): self.cmd.pop(0) return else: self.cmd = alias + self.cmd[1:] # resolve any redirects the aliases may have applied self.redirect_leading() self.redirect_trailing() if self.binary_loc is None: return try: self.cmd = get_script_subproc_command(self.binary_loc, self.cmd[1:]) except PermissionError: e = 'xonsh: subprocess mode: permission denied: {0}' raise XonshError(e.format(self.cmd[0]))
[docs] def resolve_alias_cls(self): """Determine which proxy class to run an alias with.""" alias = self.alias if not callable(alias): return self.is_proxy = True thable = getattr(alias, '__xonsh_threadable__', True) cls = ProcProxyThread if thable else ProcProxy self.cls = cls self.threadable = thable # also check capturablity, while we are here cpable = getattr(alias, '__xonsh_capturable__', self.captured) self.captured = cpable
def _safe_pipe_properties(fd, use_tty=False): """Makes sure that a pipe file descriptor properties are sane.""" if not use_tty: return # due to some weird, long standing issue in Python, PTYs come out # replacing newline \n with \r\n. This causes issues for raw unix # protocols, like git and ssh, which expect unix line endings. # see https://mail.python.org/pipermail/python-list/2013-June/650460.html # for more details and the following solution. props = termios.tcgetattr(fd) props[1] = props[1] & (~termios.ONLCR) | termios.ONLRET termios.tcsetattr(fd, termios.TCSANOW, props) def _update_last_spec(last): captured = last.captured last.last_in_pipeline = True if not captured: return callable_alias = callable(last.alias) if callable_alias: pass else: cmds_cache = builtins.__xonsh_commands_cache__ thable = (cmds_cache.predict_threadable(last.args) and cmds_cache.predict_threadable(last.cmd)) if captured and thable: last.cls = PopenThread elif not thable: # foreground processes should use Popen last.threadable = False if captured == 'object' or captured == 'hiddenobject': # CommandPipeline objects should not pipe stdout, stderr return # cannot used PTY pipes for aliases, for some dark reason, # and must use normal pipes instead. use_tty = ON_POSIX and not callable_alias # Do not set standard in! Popen is not a fan of redirections here # set standard out if last.stdout is not None: last.universal_newlines = True elif captured in STDOUT_CAPTURE_KINDS: last.universal_newlines = False r, w = os.pipe() last.stdout = safe_open(w, 'wb') last.captured_stdout = safe_open(r, 'rb') elif builtins.__xonsh_stdout_uncaptured__ is not None: last.universal_newlines = True last.stdout = builtins.__xonsh_stdout_uncaptured__ last.captured_stdout = last.stdout elif ON_WINDOWS and not callable_alias: last.universal_newlines = True last.stdout = None # must truly stream on windows last.captured_stdout = ConsoleParallelReader(1) else: last.universal_newlines = True r, w = pty.openpty() if use_tty else os.pipe() _safe_pipe_properties(w, use_tty=use_tty) last.stdout = safe_open(w, 'w') _safe_pipe_properties(r, use_tty=use_tty) last.captured_stdout = safe_open(r, 'r') # set standard error if last.stderr is not None: pass elif captured == 'object': r, w = os.pipe() last.stderr = safe_open(w, 'w') last.captured_stderr = safe_open(r, 'r') elif builtins.__xonsh_stderr_uncaptured__ is not None: last.stderr = builtins.__xonsh_stderr_uncaptured__ last.captured_stderr = last.stderr elif ON_WINDOWS and not callable_alias: last.universal_newlines = True last.stderr = None # must truly stream on windows else: r, w = pty.openpty() if use_tty else os.pipe() _safe_pipe_properties(w, use_tty=use_tty) last.stderr = safe_open(w, 'w') _safe_pipe_properties(r, use_tty=use_tty) last.captured_stderr = safe_open(r, 'r') # redirect stdout to stderr, if we should if isinstance(last.stdout, int) and last.stdout == 2: # need to use private interface to avoid duplication. last._stdout = last.stderr
[docs]def cmds_to_specs(cmds, captured=False): """Converts a list of cmds to a list of SubprocSpec objects that are ready to be executed. """ # first build the subprocs independently and separate from the redirects specs = [] redirects = [] for cmd in cmds: if isinstance(cmd, str): redirects.append(cmd) else: if cmd[-1] == '&': cmd = cmd[:-1] redirects.append('&') spec = SubprocSpec.build(cmd, captured=captured) specs.append(spec) # now modify the subprocs based on the redirects. for i, redirect in enumerate(redirects): if redirect == '|': # these should remain integer file descriptors, and not Python # file objects since they connect processes. r, w = os.pipe() specs[i].stdout = w specs[i + 1].stdin = r elif redirect == '&' and i == len(redirects) - 1: specs[-1].background = True else: raise XonshError('unrecognized redirect {0!r}'.format(redirect)) # Apply boundry conditions _update_last_spec(specs[-1]) return specs
def _should_set_title(captured=False): env = builtins.__xonsh_env__ return (env.get('XONSH_INTERACTIVE') and not env.get('XONSH_STORE_STDOUT') and captured not in STDOUT_CAPTURE_KINDS and hasattr(builtins, '__xonsh_shell__'))
[docs]def run_subproc(cmds, captured=False): """Runs a subprocess, in its many forms. This takes a list of 'commands,' which may be a list of command line arguments or a string, representing a special connecting character. For example:: $ ls | grep wakka is represented by the following cmds:: [['ls'], '|', ['grep', 'wakka']] Lastly, the captured argument affects only the last real command. """ specs = cmds_to_specs(cmds, captured=captured) captured = specs[-1].captured if captured == 'hiddenobject': command = HiddenCommandPipeline(specs) else: command = CommandPipeline(specs) proc = command.proc background = command.spec.background if not all(x.is_proxy for x in specs): add_job({ 'cmds': cmds, 'pids': [i.pid for i in command.procs], 'obj': proc, 'bg': background, 'pipeline': command, 'pgrp': command.term_pgid, }) if _should_set_title(captured=captured): # set title here to get currently executing command pause_call_resume(proc, builtins.__xonsh_shell__.settitle) # create command or return if backgrounding. if background: return # now figure out what we should return. if captured == 'stdout': command.end() return command.output elif captured == 'object': return command elif captured == 'hiddenobject': command.end() return command else: command.end() return
[docs]def subproc_captured_stdout(*cmds): """Runs a subprocess, capturing the output. Returns the stdout that was produced as a str. """ return run_subproc(cmds, captured='stdout')
[docs]def subproc_captured_inject(*cmds): """Runs a subprocess, capturing the output. Returns a list of whitespace-separated strings of the stdout that was produced. The string is split using xonsh's lexer, rather than Python's str.split() or shlex.split(). """ s = run_subproc(cmds, captured='stdout') toks = builtins.__xonsh_execer__.parser.lexer.split(s.strip()) return toks
[docs]def subproc_captured_object(*cmds): """ Runs a subprocess, capturing the output. Returns an instance of CommandPipeline representing the completed command. """ return run_subproc(cmds, captured='object')
[docs]def subproc_captured_hiddenobject(*cmds): """Runs a subprocess, capturing the output. Returns an instance of HiddenCommandPipeline representing the completed command. """ return run_subproc(cmds, captured='hiddenobject')
[docs]def subproc_uncaptured(*cmds): """Runs a subprocess, without capturing the output. Returns the stdout that was produced as a str. """ return run_subproc(cmds, captured=False)
[docs]def ensure_list_of_strs(x): """Ensures that x is a list of strings.""" if isinstance(x, str): rtn = [x] elif isinstance(x, cabc.Sequence): rtn = [i if isinstance(i, str) else str(i) for i in x] else: rtn = [str(x)] return rtn
[docs]def list_of_strs_or_callables(x): """Ensures that x is a list of strings or functions""" if isinstance(x, str) or callable(x): rtn = [x] elif isinstance(x, cabc.Iterable): rtn = [i if isinstance(i, str) or callable(i) else str(i) for i in x] else: rtn = [str(x)] return rtn
@lazyobject def MACRO_FLAG_KINDS(): return { 's': str, 'str': str, 'string': str, 'a': AST, 'ast': AST, 'c': types.CodeType, 'code': types.CodeType, 'compile': types.CodeType, 'v': eval, 'eval': eval, 'x': exec, 'exec': exec, 't': type, 'type': type, } def _convert_kind_flag(x): """Puts a kind flag (string) a canonical form.""" x = x.lower() kind = MACRO_FLAG_KINDS.get(x, None) if kind is None: raise TypeError('{0!r} not a recognized macro type.'.format(x)) return kind
[docs]def convert_macro_arg(raw_arg, kind, glbs, locs, *, name='<arg>', macroname='<macro>'): """Converts a string macro argument based on the requested kind. Parameters ---------- raw_arg : str The str reprensetaion of the macro argument. kind : object A flag or type representing how to convert the argument. glbs : Mapping The globals from the call site. locs : Mapping or None The locals from the call site. name : str, optional The macro argument name. macroname : str, optional The name of the macro itself. Returns ------- The converted argument. """ # munge kind and mode to start mode = None if isinstance(kind, cabc.Sequence) and not isinstance(kind, str): # have (kind, mode) tuple kind, mode = kind if isinstance(kind, str): kind = _convert_kind_flag(kind) if kind is str or kind is None: return raw_arg # short circut since there is nothing else to do # select from kind and convert execer = builtins.__xonsh_execer__ filename = macroname + '(' + name + ')' if kind is AST: ctx = set(dir(builtins)) | set(glbs.keys()) if locs is not None: ctx |= set(locs.keys()) mode = mode or 'eval' arg = execer.parse(raw_arg, ctx, mode=mode, filename=filename) elif kind is types.CodeType or kind is compile: # NOQA mode = mode or 'eval' arg = execer.compile(raw_arg, mode=mode, glbs=glbs, locs=locs, filename=filename) elif kind is eval: arg = execer.eval(raw_arg, glbs=glbs, locs=locs, filename=filename) elif kind is exec: mode = mode or 'exec' if not raw_arg.endswith('\n'): raw_arg += '\n' arg = execer.exec(raw_arg, mode=mode, glbs=glbs, locs=locs, filename=filename) elif kind is type: arg = type(execer.eval(raw_arg, glbs=glbs, locs=locs, filename=filename)) else: msg = ('kind={0!r} and mode={1!r} was not recongnized for macro ' 'argument {2!r}') raise TypeError(msg.format(kind, mode, name)) return arg
@contextlib.contextmanager
[docs]def in_macro_call(f, glbs, locs): """Attaches macro globals and locals temporarily to function as a context manager. Parameters ---------- f : callable object The function that is called as ``f(*args)``. glbs : Mapping The globals from the call site. locs : Mapping or None The locals from the call site. """ prev_glbs = getattr(f, 'macro_globals', None) prev_locs = getattr(f, 'macro_locals', None) f.macro_globals = glbs f.macro_locals = locs yield if prev_glbs is None: del f.macro_globals else: f.macro_globals = prev_glbs if prev_locs is None: del f.macro_locals else: f.macro_locals = prev_locs
[docs]def call_macro(f, raw_args, glbs, locs): """Calls a function as a macro, returning its result. Parameters ---------- f : callable object The function that is called as ``f(*args)``. raw_args : tuple of str The str reprensetaion of arguments of that were passed into the macro. These strings will be parsed, compiled, evaled, or left as a string dependending on the annotations of f. glbs : Mapping The globals from the call site. locs : Mapping or None The locals from the call site. """ sig = inspect.signature(f) empty = inspect.Parameter.empty macroname = f.__name__ i = 0 args = [] for (key, param), raw_arg in zip(sig.parameters.items(), raw_args): i += 1 if raw_arg == '*': break kind = param.annotation if kind is empty or kind is None: kind = str arg = convert_macro_arg(raw_arg, kind, glbs, locs, name=key, macroname=macroname) args.append(arg) reg_args, kwargs = _eval_regular_args(raw_args[i:], glbs, locs) args += reg_args with in_macro_call(f, glbs, locs): rtn = f(*args, **kwargs) return rtn
@lazyobject def KWARG_RE(): return re.compile('([A-Za-z_]\w*=|\*\*)') def _starts_as_arg(s): """Tests if a string starts as a non-kwarg string would.""" return KWARG_RE.match(s) is None def _eval_regular_args(raw_args, glbs, locs): if not raw_args: return [], {} arglist = list(itertools.takewhile(_starts_as_arg, raw_args)) kwarglist = raw_args[len(arglist):] execer = builtins.__xonsh_execer__ if not arglist: args = arglist kwargstr = 'dict({})'.format(', '.join(kwarglist)) kwargs = execer.eval(kwargstr, glbs=glbs, locs=locs) elif not kwarglist: argstr = '({},)'.format(', '.join(arglist)) args = execer.eval(argstr, glbs=glbs, locs=locs) kwargs = {} else: argstr = '({},)'.format(', '.join(arglist)) kwargstr = 'dict({})'.format(', '.join(kwarglist)) both = '({}, {})'.format(argstr, kwargstr) args, kwargs = execer.eval(both, glbs=glbs, locs=locs) return args, kwargs
[docs]def enter_macro(obj, raw_block, glbs, locs): """Prepares to enter a context manager macro by attaching the contents of the macro block, globals, and locals to the object. These modifications are made in-place and the original object is returned. Parameters ---------- obj : context manager The object that is about to be entered via a with-statement. raw_block : str The str of the block that is the context body. This string will be parsed, compiled, evaled, or left as a string dependending on the return annotation of obj.__enter__. glbs : Mapping The globals from the context site. locs : Mapping or None The locals from the context site. Returns ------- obj : context manager The same context manager but with the new macro information applied. """ # recurse down sequences if isinstance(obj, cabc.Sequence): for x in obj: enter_macro(x, raw_block, glbs, locs) return obj # convert block as needed kind = getattr(obj, '__xonsh_block__', str) macroname = getattr(obj, '__name__', '<context>') block = convert_macro_arg(raw_block, kind, glbs, locs, name='<with!>', macroname=macroname) # attach attrs obj.macro_globals = glbs obj.macro_locals = locs obj.macro_block = block return obj
[docs]def load_builtins(execer=None, ctx=None): """Loads the xonsh builtins into the Python builtins. Sets the BUILTINS_LOADED variable to True. """ global BUILTINS_LOADED # private built-ins builtins.__xonsh_config__ = {} builtins.__xonsh_env__ = Env(default_env()) builtins.__xonsh_help__ = helper builtins.__xonsh_superhelp__ = superhelper builtins.__xonsh_pathsearch__ = pathsearch builtins.__xonsh_globsearch__ = globsearch builtins.__xonsh_regexsearch__ = regexsearch builtins.__xonsh_glob__ = globpath builtins.__xonsh_expand_path__ = expand_path builtins.__xonsh_exit__ = False builtins.__xonsh_stdout_uncaptured__ = None builtins.__xonsh_stderr_uncaptured__ = None if hasattr(builtins, 'exit'): builtins.__xonsh_pyexit__ = builtins.exit del builtins.exit if hasattr(builtins, 'quit'): builtins.__xonsh_pyquit__ = builtins.quit del builtins.quit builtins.__xonsh_subproc_captured_stdout__ = subproc_captured_stdout builtins.__xonsh_subproc_captured_inject__ = subproc_captured_inject builtins.__xonsh_subproc_captured_object__ = subproc_captured_object builtins.__xonsh_subproc_captured_hiddenobject__ = subproc_captured_hiddenobject builtins.__xonsh_subproc_uncaptured__ = subproc_uncaptured builtins.__xonsh_execer__ = execer builtins.__xonsh_commands_cache__ = CommandsCache() builtins.__xonsh_all_jobs__ = {} builtins.__xonsh_ensure_list_of_strs__ = ensure_list_of_strs builtins.__xonsh_list_of_strs_or_callables__ = list_of_strs_or_callables builtins.__xonsh_completers__ = xonsh.completers.init.default_completers() builtins.__xonsh_call_macro__ = call_macro builtins.__xonsh_enter_macro__ = enter_macro builtins.__xonsh_path_literal__ = path_literal # public built-ins builtins.XonshError = XonshError builtins.XonshCalledProcessError = XonshCalledProcessError builtins.evalx = None if execer is None else execer.eval builtins.execx = None if execer is None else execer.exec builtins.compilex = None if execer is None else execer.compile builtins.events = events # sneak the path search functions into the aliases # Need this inline/lazy import here since we use locate_binary that # relies on __xonsh_env__ in default aliases builtins.default_aliases = builtins.aliases = Aliases(make_default_aliases()) builtins.__xonsh_history__ = None atexit.register(_lastflush) for sig in AT_EXIT_SIGNALS: resetting_signal_handle(sig, _lastflush) BUILTINS_LOADED = True
def _lastflush(s=None, f=None): if hasattr(builtins, '__xonsh_history__'): if builtins.__xonsh_history__ is not None: builtins.__xonsh_history__.flush(at_exit=True)
[docs]def unload_builtins(): """Removes the xonsh builtins from the Python builtins, if the BUILTINS_LOADED is True, sets BUILTINS_LOADED to False, and returns. """ global BUILTINS_LOADED env = getattr(builtins, '__xonsh_env__', None) if isinstance(env, Env): env.undo_replace_env() if hasattr(builtins, '__xonsh_pyexit__'): builtins.exit = builtins.__xonsh_pyexit__ if hasattr(builtins, '__xonsh_pyquit__'): builtins.quit = builtins.__xonsh_pyquit__ if not BUILTINS_LOADED: return names = ['__xonsh_config__', '__xonsh_env__', '__xonsh_ctx__', '__xonsh_help__', '__xonsh_superhelp__', '__xonsh_pathsearch__', '__xonsh_globsearch__', '__xonsh_regexsearch__', '__xonsh_glob__', '__xonsh_expand_path__', '__xonsh_exit__', '__xonsh_stdout_uncaptured__', '__xonsh_stderr_uncaptured__', '__xonsh_pyexit__', '__xonsh_pyquit__', '__xonsh_subproc_captured_stdout__', '__xonsh_subproc_captured_inject__', '__xonsh_subproc_captured_object__', '__xonsh_subproc_captured_hiddenobject__', '__xonsh_subproc_uncaptured__', '__xonsh_execer__', '__xonsh_commands_cache__', '__xonsh_completers__', '__xonsh_call_macro__', '__xonsh_enter_macro__', '__xonsh_path_literal__', 'XonshError', 'XonshCalledProcessError', 'evalx', 'execx', 'compilex', 'default_aliases', '__xonsh_all_jobs__', '__xonsh_ensure_list_of_strs__', '__xonsh_list_of_strs_or_callables__', '__xonsh_history__', ] for name in names: if hasattr(builtins, name): delattr(builtins, name) BUILTINS_LOADED = False
@contextlib.contextmanager
[docs]def xonsh_builtins(execer=None): """A context manager for using the xonsh builtins only in a limited scope. Likely useful in testing. """ load_builtins(execer=execer) yield unload_builtins()