Source code for Muscat.Helpers.IO.Which

# -*- coding: utf-8 -*-
#
# This file is subject to the terms and conditions defined in
# file 'LICENSE.txt', which is part of this source code package.
#
from typing import Union
import os


def Which(program: str) -> str:
    """Check if an executable is reachable
    and return the real "executable" (with the .exe or .bat )

    inspiration from:
        https://stackoverflow.com/questions/377017/test-if-executable-exists-in-python

    Parameters
    ----------
    program : str
        the name of the program to find, in windows the user can omit the .exe or the .bat
        extension

    Returns
    -------
    str
        return the string of the real executable or and empty string if the executable is not found
    """

    def is_exe(fpath: str) -> bool:
        """Helper function the check if a file is exist and has the execution rights

        Parameters
        ----------
        fpath : str
            absolute path to a file

        Returns
        -------
        bool
            true if exists, is a file , has executable permission
        """
        return os.path.isfile(fpath) and os.access(fpath, os.X_OK)

    fpath = os.path.dirname(program)

    if fpath:
        # we have a path so we search for the exact filename
        if is_exe(program):
            return program
    else:
        for path in os.environ["PATH"].split(os.pathsep):
            path = path.strip('"')
            exe_file = os.path.join(path, program)
            if is_exe(exe_file):  # pragma: no coverage (check the user path, not possible to test this)
                return exe_file
            if os.name == "nt":  # only nt coverage
                try:
                    from win32api import FindExecutable, GetLongPathName
                    _, executable = FindExecutable(program)
                except:
                    from Muscat.Helpers.Logger import Warning
                    Warning("module win32api is missing, you executable may not be found")
                else:
                    if os.path.isfile(executable):
                        return executable

    return ""


def CheckIntegrity(GUI: bool = False) -> str:
    from Muscat.Helpers.IO.Which import Which

    if os.name == "nt":  # only nt coverage
        # print(Which('explorer'))
        print(Which('explorer'), 'C:\\WINDOWS\\explorer.exe')
        print(Which("explorer.exe"), 'C:\\WINDOWS\\explorer.exe')
        print(Which("C:\\WINDOWS\\explorer.exe"), 'C:\\WINDOWS\\explorer.exe')
        assert (Which('None_Existent_executable_like_ls') == "")

    else:  # only posix coverage
        print(Which('ls'))
        assert (Which('ls') == "/usr/bin/ls")
        assert (Which('/usr/bin/ls') == "/usr/bin/ls")
        assert (Which('explorer') == "")

    return "OK"


if __name__ == '__main__':  # pragma: no cover
    print(CheckIntegrity(True))