tabcompleter.py

"""
tabcompleter: Python console tab-completion. Replaces fancycompleter.
=====================================================================
"""
import rlcompleter
import sys
import types
import os.path
from itertools import count


class LazyVersion(object):
    def __init__(self, pkg):
        self.pkg = pkg
        self.__version = None

    @property
    def version(self):
        if self.__version is None:
            self.__version = self._load_version()
        return self.__version

    def _load_version(self):
        try:
            from pkg_resources import get_distribution, DistributionNotFound
        except ImportError:
            return "N/A"
        try:
            return get_distribution(self.pkg).version
        except DistributionNotFound:
            return "N/A"

    def __repr__(self):
        return self.version

    def __eq__(self, other):
        return self.version == other

    def __ne__(self, other):
        return not self == other


__version__ = LazyVersion(__name__)


class Color:
    black = "30"
    darkred = "31"
    darkgreen = "32"
    brown = "33"
    darkblue = "34"
    purple = "35"
    teal = "36"
    lightgray = "37"
    darkgray = "30;01"
    red = "31;01"
    green = "32;01"
    yellow = "33;01"
    blue = "34;01"
    fuchsia = "35;01"
    turquoise = "36;01"
    white = "37;01"

    @classmethod
    def set(cls, color, string):
        try:
            color = getattr(cls, color)
        except AttributeError:
            pass
        return "\x1b[%sm%s\x1b[00m" % (color, string)


class DefaultConfig:
    consider_getitems = True
    use_colors = "auto"
    readline = None
    color_by_type = {
        types.BuiltinMethodType: Color.turquoise,
        types.MethodType: Color.turquoise,
        type((42).__add__): Color.turquoise,
        type(int.__add__): Color.turquoise,
        type(str.replace): Color.turquoise,
        types.FunctionType: Color.blue,
        types.BuiltinFunctionType: Color.blue,
        type: Color.fuchsia,
        types.ModuleType: Color.teal,
        type(None): Color.lightgray,
        str: Color.green,
        int: Color.yellow,
        float: Color.yellow,
        complex: Color.yellow,
        bool: Color.yellow,
    }
    color_by_baseclass = [
        ((BaseException,), Color.red),
    ]

    def find_pyreadline(self):
        try:
            import readline
            import pyreadline  # noqa: F401
            from pyreadline.modes import basemode
        except ImportError:
            return None
        if hasattr(basemode, "stripcolor"):
            return readline, True
        else:
            return readline, False

    def find_best_readline(self):
        if sys.platform == "win32":
            result = self.find_pyreadline()
            if result:
                return result
        import readline
        return readline, False

    def setup(self):
        self.readline, supports_color = self.find_best_readline()
        if self.use_colors == "auto":
            self.use_colors = supports_color


def my_execfile(filename, mydict):
    with open(filename) as f:
        code = compile(f.read(), filename, "exec")
        exec(code, mydict)


class ConfigurableClass:
    DefaultConfig = None
    config_filename = None

    def get_config(self, Config):
        if Config is not None:
            return Config()
        filename = "~/" + self.config_filename
        rcfile = os.path.normpath(os.path.expanduser(filename))
        if not os.path.exists(rcfile):
            return self.DefaultConfig()
        mydict = {}
        try:
            my_execfile(rcfile, mydict)
        except Exception as exc:
            import traceback
            sys.stderr.write(
                "** error when importing %s: %r **\n" % (filename, exc)
            )
            traceback.print_tb(sys.exc_info()[2])
            return self.DefaultConfig()
        try:
            Config = mydict["Config"]
        except KeyError:
            return self.DefaultConfig()
        try:
            return Config()
        except Exception as exc:
            err = "error when setting up Config from %s: %s" % (filename, exc)
            tb = sys.exc_info()[2]
            if tb and tb.tb_next:
                tb = tb.tb_next
                err_fname = tb.tb_frame.f_code.co_filename
                err_lnum = tb.tb_lineno
                err += " (%s:%d)" % (err_fname, err_lnum,)
            sys.stderr.write("** %s **\n" % err)
        return self.DefaultConfig()


class Completer(rlcompleter.Completer, ConfigurableClass):
    DefaultConfig = DefaultConfig
    config_filename = ".tabcompleterrc.py"

    def __init__(self, namespace=None, Config=None):
        rlcompleter.Completer.__init__(self, namespace)
        self.config = self.get_config(Config)
        self.config.setup()
        readline = self.config.readline
        if hasattr(readline, "_setup"):
            readline._setup()
        if self.config.use_colors:
            readline.parse_and_bind("set dont-escape-ctrl-chars on")
        if self.config.consider_getitems:
            delims = readline.get_completer_delims()
            delims = delims.replace("[", "")
            delims = delims.replace("]", "")
            readline.set_completer_delims(delims)

    def complete(self, text, state):
        if text == "":
            return ["\t", None][state]
        else:
            return rlcompleter.Completer.complete(self, text, state)

    def _callable_postfix(self, val, word):
        return word

    def global_matches(self, text):
        import keyword
        names = rlcompleter.Completer.global_matches(self, text)
        prefix = commonprefix(names)
        if prefix and prefix != text:
            return [prefix]

        names.sort()
        values = []
        for name in names:
            clean_name = name.rstrip(": ")
            if clean_name in keyword.kwlist:
                values.append(None)
            else:
                try:
                    values.append(eval(name, self.namespace))
                except Exception as exc:
                    values.append(exc)
        if self.config.use_colors and names:
            return self.color_matches(names, values)
        return names

    def attr_matches(self, text):
        import warnings
        warnings.simplefilter("ignore", category=DeprecationWarning)
        expr, attr = text.rsplit(".", 1)
        if "(" in expr or ")" in expr:
            return []
        try:
            thisobject = eval(expr, self.namespace)
        except Exception:
            return []
        words = set(dir(thisobject))
        words.discard("__builtins__")
        if hasattr(thisobject, "__class__"):
            words.add("__class__")
            words.update(rlcompleter.get_class_members(thisobject.__class__))
        names = []
        values = []
        n = len(attr)
        if attr == "":
            noprefix = "_"
        elif attr == "_":
            noprefix = "__"
        else:
            noprefix = None
        words = sorted(words)
        while True:
            for word in words:
                if (
                    word[:n] == attr
                    and not (noprefix and word[:n + 1] == noprefix)
                ):
                    try:
                        val = getattr(thisobject, word)
                    except Exception:
                        val = None
                    names.append(word)
                    values.append(val)
            if names or not noprefix:
                break
            if noprefix == "_":
                noprefix = "__"
            else:
                noprefix = None
        if not names:
            return []
        if len(names) == 1:
            return ["%s.%s" % (expr, names[0])]  # Only option, no coloring.
        prefix = commonprefix(names)
        if prefix and prefix != attr:
            return ["%s.%s" % (expr, prefix)]  # Autocomplete prefix.
        if self.config.use_colors:
            return self.color_matches(names, values)
        if prefix:
            names += [" "]
        return names

    def color_matches(self, names, values):
        matches = [self.color_for_obj(i, name, obj)
                   for i, name, obj
                   in zip(count(), names, values)]
        return matches + [" "]

    def color_for_obj(self, i, name, value):
        t = type(value)
        color = self.config.color_by_type.get(t, None)
        if color is None:
            for x, _color in self.config.color_by_baseclass:
                if isinstance(value, x):
                    color = _color
                    break
            else:
                color = "00"
        return "\x1b[%03d;00m" % i + Color.set(color, name)


def commonprefix(names, base=""):
    if base:
        names = [x for x in names if x.startswith(base)]
    if not names:
        return ""
    s1 = min(names)
    s2 = max(names)
    for i, c in enumerate(s1):
        if c != s2[i]:
            return s1[:i]
    return s1


def has_leopard_libedit(config):
    if sys.platform != "darwin":
        return False
    return config.readline.__doc__ and "libedit" in config.readline.__doc__


def setup():
    """Install tabcompleter as the default completer for readline."""
    completer = Completer()
    readline = completer.config.readline
    if has_leopard_libedit(completer.config):
        readline.parse_and_bind("bind ^I rl_complete")
    else:
        readline.parse_and_bind("tab: complete")
    readline.set_completer(completer.complete)
    return completer


def setup_history(completer, persist_history):
    import atexit
    readline = completer.config.readline
    if isinstance(persist_history, str):
        filename = persist_history
    else:
        filename = "~/.history.py"
    filename = os.path.expanduser(filename)
    if os.path.isfile(filename):
        readline.read_history_file(filename)

    def save_history():
        readline.write_history_file(filename)
    atexit.register(save_history)


def interact(persist_history=None):
    completer = setup()
    if persist_history:
        setup_history(completer, persist_history)


class Installer(object):
    def __init__(self, basepath, force):
        fname = os.path.join(basepath, "python_startup.py")
        self.filename = os.path.expanduser(fname)
        self.force = force

    def check(self):
        PYTHONSTARTUP = os.environ.get("PYTHONSTARTUP")
        if PYTHONSTARTUP:
            return "PYTHONSTARTUP already defined: %s" % PYTHONSTARTUP
        if os.path.exists(self.filename):
            return "%s already exists" % self.filename

    def install(self):
        import textwrap
        error = self.check()
        if error and not self.force:
            print(error)
            print("Use --force to overwrite.")
            return False
        with open(self.filename, "w") as f:
            f.write(
                textwrap.dedent(
                    """
                    import tabcompleter
                    tabcompleter.interact(persist_history=True)
                    """
                )
            )
        self.set_env_var()
        return True

    def set_env_var(self):
        if sys.platform == "win32":
            os.system('SETX PYTHONSTARTUP "%s"' % self.filename)
            print("%PYTHONSTARTUP% set to", self.filename)
        else:
            print("startup file written to", self.filename)
            print("Append this line to your ~/.bashrc:")
            print("    export PYTHONSTARTUP=%s" % self.filename)


if __name__ == "__main__":
    def usage():
        print("Usage: python -m tabcompleter install [-f|--force]")
        sys.exit(1)

    cmd = None
    force = False
    for item in sys.argv[1:]:
        if item in ("install",):
            cmd = item
        elif item in ("-f", "--force"):
            force = True
        else:
            usage()
    if cmd == "install":
        installer = Installer("~", force)
        installer.install()
    else:
        usage()