TestCmd.py

"""
TestCmd.py:  a testing framework for commands and scripts.

The TestCmd module provides a framework for portable automated testing of
executable commands and scripts (in any language, not just Python), especially
commands and scripts that require file system interaction.

In addition to running tests and evaluating conditions, the TestCmd module
manages and cleans up one or more temporary workspace directories, and provides
methods for creating files and directories in those workspace directories from
in-line data, here-documents), allowing tests to be completely self-contained.

A TestCmd environment object is created via the usual invocation:

    test = TestCmd()

The TestCmd module provides pass_test(), fail_test(), and no_result() unbound
methods that report test results for use with the Aegis change management
system. These methods terminate the test immediately, reporting PASSED, FAILED
or NO RESULT respectively and exiting with status 0 (success), 1 or 2
respectively. This allows for a distinction between an actual failed test and a
test that could not be properly evaluated because of an external condition (such
as a full file system or incorrect permissions).

"""

# Copyright 2000 Steven Knight
# This module is free software, and you may redistribute it and/or modify
# it under the same terms as Python itself, so long as this copyright message
# and disclaimer are retained in their original form.
#
# IN NO EVENT SHALL THE AUTHOR BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
# SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF
# THIS CODE, EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
# DAMAGE.
#
# THE AUTHOR SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
# PARTICULAR PURPOSE.  THE CODE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS,
# AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
# SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

# Copyright 2002-2003 Vladimir Prus.
# Copyright 2002-2003 Dave Abrahams.
# Copyright 2006 Rene Rivera.
# Distributed under the Boost Software License, Version 1.0.
#    (See accompanying file LICENSE.txt or copy at
#         https://www.bfgroup.xyz/b2/LICENSE.txt)

from __future__ import print_function

__author__ = "Steven Knight <knight@baldmt.com>"
__revision__ = "TestCmd.py 0.D002 2001/08/31 14:56:12 software"
__version__ = "0.02"

from types import *

import os
import os.path
import re
import shutil
import stat
import subprocess
import sys
import tempfile
import traceback


tempfile.template = 'testcmd.'

_Cleanup = []

def _clean():
    global _Cleanup
    list = _Cleanup[:]
    _Cleanup = []
    list.reverse()
    for test in list:
        test.cleanup()

sys.exitfunc = _clean


def caller(tblist, skip):
    string = ""
    arr = []
    for file, line, name, text in tblist:
        if file[-10:] == "TestCmd.py":
                break
        arr = [(file, line, name, text)] + arr
    atfrom = "at"
    for file, line, name, text in arr[skip:]:
        if name == "?":
            name = ""
        else:
            name = " (" + name + ")"
        string = string + ("%s line %d of %s%s\n" % (atfrom, line, file, name))
        atfrom = "\tfrom"
    return string


def fail_test(self=None, condition=True, function=None, skip=0):
    """Cause the test to fail.

      By default, the fail_test() method reports that the test FAILED and exits
    with a status of 1. If a condition argument is supplied, the test fails
    only if the condition is true.

    """
    if not condition:
        return
    if not function is None:
        function()
    of = ""
    desc = ""
    sep = " "
    if not self is None:
        if self.program:
            of = " of " + " ".join(self.program)
            sep = "\n\t"
        if self.description:
            desc = " [" + self.description + "]"
            sep = "\n\t"

    at = caller(traceback.extract_stack(), skip)

    sys.stderr.write("FAILED test" + of + desc + sep + at + """
in directory: """ + os.getcwd() )
    sys.exit(1)


def no_result(self=None, condition=True, function=None, skip=0):
    """Causes a test to exit with no valid result.

      By default, the no_result() method reports NO RESULT for the test and
    exits with a status of 2. If a condition argument is supplied, the test
    fails only if the condition is true.

    """
    if not condition:
        return
    if not function is None:
        function()
    of = ""
    desc = ""
    sep = " "
    if not self is None:
        if self.program:
            of = " of " + self.program
            sep = "\n\t"
        if self.description:
            desc = " [" + self.description + "]"
            sep = "\n\t"

    at = caller(traceback.extract_stack(), skip)
    sys.stderr.write("NO RESULT for test" + of + desc + sep + at)
    sys.exit(2)


def pass_test(self=None, condition=True, function=None):
    """Causes a test to pass.

      By default, the pass_test() method reports PASSED for the test and exits
    with a status of 0. If a condition argument is supplied, the test passes
    only if the condition is true.

    """
    if not condition:
        return
    if not function is None:
        function()
    sys.stderr.write("PASSED\n")
    sys.exit(0)

class MatchError(object):
    def __init__(self, message):
        self.message = message
    def __nonzero__(self):
        return False
    def __bool__(self):
        return False

def match_exact(lines=None, matches=None):
    """
      Returns whether the given lists or strings containing lines separated
    using newline characters contain exactly the same data.

    """
    if not type(lines) is list:
        lines = lines.split("\n")
    if not type(matches) is list:
        matches = matches.split("\n")
    if len(lines) != len(matches):
        return
    for i in range(len(lines)):
        if lines[i] != matches[i]:
            return MatchError("Mismatch at line %d\n- %s\n+ %s\n" %
                (i+1, matches[i], lines[i]))
    if len(lines) < len(matches):
        return MatchError("Missing lines at line %d\n- %s" %
            (len(lines), "\n- ".join(matches[len(lines):])))
    if len(lines) > len(matches):
        return MatchError("Extra lines at line %d\n+ %s" %
            (len(matches), "\n+ ".join(lines[len(matches):])))
    return 1


def match_re(lines=None, res=None):
    """
      Given lists or strings contain lines separated using newline characters.
    This function matches those lines one by one, interpreting the lines in the
    res parameter as regular expressions.

    """
    if not type(lines) is list:
        lines = lines.split("\n")
    if not type(res) is list:
        res = res.split("\n")
    for i in range(min(len(lines), len(res))):
        if not re.compile("^" + res[i] + "$").search(lines[i]):
            return MatchError("Mismatch at line %d\n- %s\n+ %s\n" %
                (i+1, res[i], lines[i]))
    if len(lines) < len(res):
        return MatchError("Missing lines at line %d\n- %s" %
            (len(lines), "\n- ".join(res[len(lines):])))
    if len(lines) > len(res):
        return MatchError("Extra lines at line %d\n+ %s" %
            (len(res), "\n+ ".join(lines[len(res):])))
    return 1


class TestCmd:
    def __init__(self, description=None, program=None, workdir=None,
        subdir=None, verbose=False, match=None, inpath=None):

        self._cwd = os.getcwd()
        self.description_set(description)
        self.program_set(program, inpath)
        self.verbose_set(verbose)
        if match is None:
            self.match_func = match_re
        else:
            self.match_func = match
        self._dirlist = []
        self._preserve = {'pass_test': 0, 'fail_test': 0, 'no_result': 0}
        env = os.environ.get('PRESERVE')
        if env:
            self._preserve['pass_test'] = env
            self._preserve['fail_test'] = env
            self._preserve['no_result'] = env
        else:
            env = os.environ.get('PRESERVE_PASS')
            if env is not None:
                self._preserve['pass_test'] = env
            env = os.environ.get('PRESERVE_FAIL')
            if env is not None:
                self._preserve['fail_test'] = env
            env = os.environ.get('PRESERVE_PASS')
            if env is not None:
                self._preserve['PRESERVE_NO_RESULT'] = env
        self._stdout = []
        self._stderr = []
        self.status = None
        self.condition = 'no_result'
        self.workdir_set(workdir)
        self.subdir(subdir)

    def __del__(self):
        self.cleanup()

    def __repr__(self):
        return "%x" % id(self)

    def cleanup(self, condition=None):
        """
          Removes any temporary working directories for the specified TestCmd
        environment. If the environment variable PRESERVE was set when the
        TestCmd environment was created, temporary working directories are not
        removed. If any of the environment variables PRESERVE_PASS,
        PRESERVE_FAIL or PRESERVE_NO_RESULT were set when the TestCmd
        environment was created, then temporary working directories are not
        removed if the test passed, failed or had no result, respectively.
        Temporary working directories are also preserved for conditions
        specified via the preserve method.

          Typically, this method is not called directly, but is used when the
        script exits to clean up temporary working directories as appropriate
        for the exit status.

        """
        if not self._dirlist:
            return
        if condition is None:
            condition = self.condition
        if self._preserve[condition]:
            for dir in self._dirlist:
                print("Preserved directory %s" % dir)
        else:
            list = self._dirlist[:]
            list.reverse()
            for dir in list:
                self.writable(dir, 1)
                shutil.rmtree(dir, ignore_errors=True)

        self._dirlist = []
        self.workdir = None
        os.chdir(self._cwd)
        try:
            global _Cleanup
            _Cleanup.remove(self)
        except (AttributeError, ValueError):
            pass

    def description_set(self, description):
        """Set the description of the functionality being tested."""
        self.description = description

    def fail_test(self, condition=True, function=None, skip=0):
        """Cause the test to fail."""
        if not condition:
            return
        self.condition = 'fail_test'
        fail_test(self = self,
                  condition = condition,
                  function = function,
                  skip = skip)

    def match(self, lines, matches):
        """Compare actual and expected file contents."""
        return self.match_func(lines, matches)

    def match_exact(self, lines, matches):
        """Compare actual and expected file content exactly."""
        return match_exact(lines, matches)

    def match_re(self, lines, res):
        """Compare file content with a regular expression."""
        return match_re(lines, res)

    def no_result(self, condition=True, function=None, skip=0):
        """Report that the test could not be run."""
        if not condition:
            return
        self.condition = 'no_result'
        no_result(self = self,
                  condition = condition,
                  function = function,
                  skip = skip)

    def pass_test(self, condition=True, function=None):
        """Cause the test to pass."""
        if not condition:
            return
        self.condition = 'pass_test'
        pass_test(self, condition, function)

    def preserve(self, *conditions):
        """
          Arrange for the temporary working directories for the specified
        TestCmd environment to be preserved for one or more conditions. If no
        conditions are specified, arranges for the temporary working
        directories to be preserved for all conditions.

        """
        if conditions == ():
            conditions = ('pass_test', 'fail_test', 'no_result')
        for cond in conditions:
            self._preserve[cond] = 1

    def program_set(self, program, inpath):
        """Set the executable program or script to be tested."""
        if not inpath and program and not os.path.isabs(program[0]):
            program[0] = os.path.join(self._cwd, program[0])
        self.program = program

    def read(self, file, mode='rb'):
        """
          Reads and returns the contents of the specified file name. The file
        name may be a list, in which case the elements are concatenated with
        the os.path.join() method. The file is assumed to be under the
        temporary working directory unless it is an absolute path name. The I/O
        mode for the file may be specified and must begin with an 'r'. The
        default is 'rb' (binary read).

        """
        if type(file) is list:
            file = os.path.join(*file)
        if not os.path.isabs(file):
            file = os.path.join(self.workdir, file)
        if mode[0] != 'r':
            raise ValueError("mode must begin with 'r'")
        return open(file, mode).read()

    def run(self, program=None, arguments=None, chdir=None, stdin=None,
        universal_newlines=True):
        """
          Runs a test of the program or script for the test environment.
        Standard output and error output are saved for future retrieval via the
        stdout() and stderr() methods.

          'universal_newlines' parameter controls how the child process
        input/output streams are opened as defined for the same named Python
        subprocess.POpen constructor parameter.

        """
        if chdir:
            if not os.path.isabs(chdir):
                chdir = os.path.join(self.workpath(chdir))
            if self.verbose:
                sys.stderr.write("chdir(" + chdir + ")\n")
        else:
            chdir = self.workdir

        cmd = []
        if program and program[0]:
            if program[0] != self.program[0] and not os.path.isabs(program[0]):
                program[0] = os.path.join(self._cwd, program[0])
            cmd += program
        else:
            cmd += self.program
        if arguments:
            cmd += arguments.split(" ")
        if self.verbose:
            sys.stderr.write("run(" + " ".join(cmd) + ")\n")
        p = subprocess.Popen(cmd, stdin=subprocess.PIPE,
            stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=chdir,
            universal_newlines=universal_newlines)

        if stdin:
            if type(stdin) is list:
                stdin = "".join(stdin)
        out, err = p.communicate(stdin)
        if not type(out) is str:
            out = out.decode()
        if not type(err) is str:
            err = err.decode()
        self._stdout.append(out)
        self._stderr.append(err)
        self.status = p.returncode

        if self.verbose:
            sys.stdout.write(self._stdout[-1])
            sys.stderr.write(self._stderr[-1])

    def stderr(self, run=None):
        """
          Returns the error output from the specified run number. If there is
        no specified run number, then returns the error output of the last run.
        If the run number is less than zero, then returns the error output from
        that many runs back from the current run.

        """
        if not run:
            run = len(self._stderr)
        elif run < 0:
            run = len(self._stderr) + run
        run -= 1
        if run < 0:
            return ''
        return self._stderr[run]

    def stdout(self, run=None):
        """
          Returns the standard output from the specified run number. If there
        is no specified run number, then returns the standard output of the
        last run. If the run number is less than zero, then returns the
        standard output from that many runs back from the current run.

        """
        if not run:
            run = len(self._stdout)
        elif run < 0:
            run = len(self._stdout) + run
        run -= 1
        if run < 0:
            return ''
        return self._stdout[run]

    def subdir(self, *subdirs):
        """
          Create new subdirectories under the temporary working directory, one
        for each argument. An argument may be a list, in which case the list
        elements are concatenated using the os.path.join() method.
        Subdirectories multiple levels deep must be created using a separate
        argument for each level:

            test.subdir('sub', ['sub', 'dir'], ['sub', 'dir', 'ectory'])

        Returns the number of subdirectories actually created.

        """
        count = 0
        for sub in subdirs:
            if sub is None:
                continue
            if type(sub) is list:
                sub = os.path.join(*tuple(sub))
            new = os.path.join(self.workdir, sub)
            try:
                os.mkdir(new)
            except:
                pass
            else:
                count += 1
        return count

    def unlink(self, file):
        """
          Unlinks the specified file name. The file name may be a list, in
        which case the elements are concatenated using the os.path.join()
        method. The file is assumed to be under the temporary working directory
        unless it is an absolute path name.

        """
        if type(file) is list:
            file = os.path.join(*tuple(file))
        if not os.path.isabs(file):
            file = os.path.join(self.workdir, file)
        os.unlink(file)

    def verbose_set(self, verbose):
        """Set the verbose level."""
        self.verbose = verbose

    def workdir_set(self, path):
        """
          Creates a temporary working directory with the specified path name.
        If the path is a null string (''), a unique directory name is created.

        """
        if os.path.isabs(path):
            self.workdir = path
        else:
            if path != None:
                if path == '':
                    path = tempfile.mkdtemp(prefix="b2")
                elif path != None:
                    os.mkdir(path)
                self._dirlist.append(path)
                global _Cleanup
                try:
                    _Cleanup.index(self)
                except ValueError:
                    _Cleanup.append(self)
                # We would like to set self.workdir like this:
                #     self.workdir = path
                # But symlinks in the path will report things differently from
                # os.getcwd(), so chdir there and back to fetch the canonical
                # path.
                cwd = os.getcwd()
                os.chdir(path)
                self.workdir = os.getcwd()
                os.chdir(cwd)
            else:
                self.workdir = None

    def workpath(self, *args):
        """
          Returns the absolute path name to a subdirectory or file within the
        current temporary working directory. Concatenates the temporary working
        directory name with the specified arguments using os.path.join().

        """
        return os.path.join(self.workdir, *tuple(args))

    def writable(self, top, write):
        """
          Make the specified directory tree writable (write == 1) or not
        (write == None).

        """
        def _walk_chmod(arg, dirname, names):
            st = os.stat(dirname)
            os.chmod(dirname, arg(st[stat.ST_MODE]))
            for name in names:
                fullname = os.path.join(dirname, name)
                st = os.stat(fullname)
                os.chmod(fullname, arg(st[stat.ST_MODE]))

        _mode_writable = lambda mode: stat.S_IMODE(mode|0o200)
        _mode_non_writable = lambda mode: stat.S_IMODE(mode&~0o200)

        if write:
            f = _mode_writable
        else:
            f = _mode_non_writable
        try:
            for root, _, files in os.walk(top):
                _walk_chmod(f, root, files)
        except:
            pass  # Ignore any problems changing modes.

    def write(self, file, content, mode='wb'):
        """
          Writes the specified content text (second argument) to the specified
        file name (first argument). The file name may be a list, in which case
        the elements are concatenated using the os.path.join() method. The file
        is created under the temporary working directory. Any subdirectories in
        the path must already exist. The I/O mode for the file may be specified
        and must begin with a 'w'. The default is 'wb' (binary write).

        """
        if type(file) is list:
            file = os.path.join(*tuple(file))
        if not os.path.isabs(file):
            file = os.path.join(self.workdir, file)
        if mode[0] != 'w':
            raise ValueError("mode must begin with 'w'")
        open(file, mode).write(content)