path: root/testing/framework/TestSCons.py

"""
TestSCons.py:  a testing framework for the SCons software construction
tool.

A TestSCons environment object is created via the usual invocation:

    test = TestSCons()

TestScons is a subclass of TestCommon, which in turn is a subclass
of TestCmd), and hence has available all of the methods and attributes
from those classes, as well as any overridden or additional methods or
attributes defined in this subclass.
"""

# Copyright (c) 2001 - 2019 The SCons Foundation
from __future__ import division, print_function

__revision__ = "testing/framework/TestSCons.py 72ae09dc35ac2626f8ff711d8c4b30b6138e08e3 2019-08-08 14:50:06 bdeegan"

import os
import re
import shutil
import sys
import time
import subprocess

from TestCommon import *
from TestCommon import __all__

from TestCmd import Popen
from TestCmd import PIPE

# Some tests which verify that SCons has been packaged properly need to
# look for specific version file names.  Replicating the version number
# here provides some independent verification that what we packaged
# conforms to what we expect.

default_version = '3.1.1'

python_version_unsupported = (2, 6, 0)
python_version_deprecated = (2, 7, 0)

# In the checked-in source, the value of SConsVersion in the following
# line must remain "__ VERSION __" (without the spaces) so the built
# version in build/testing/framework/TestSCons.py contains the actual version
# string of the packages that have been built.
SConsVersion = '3.1.1'
if SConsVersion == '__' + 'VERSION' + '__':
    SConsVersion = default_version

__all__.extend([
        'TestSCons',
        'machine',
        'python',
        '_exe',
        '_obj',
        '_shobj',
        'shobj_',
        'lib_',
        '_lib',
        'dll_',
        '_dll'
               ])

machine_map = {
    'i686'  : 'i386',
    'i586'  : 'i386',
    'i486'  : 'i386',
}

try:
    uname = os.uname
except AttributeError:
    # Windows doesn't have a uname() function.  We could use something like
    # sys.platform as a fallback, but that's not really a "machine," so
    # just leave it as None.
    machine = None
else:
    machine = uname()[4]
    machine = machine_map.get(machine, machine)

_exe = exe_suffix
_obj = obj_suffix
_shobj = shobj_suffix
shobj_ = shobj_prefix
_lib = lib_suffix
lib_ = lib_prefix
_dll = dll_suffix
dll_ = dll_prefix


if sys.platform == 'cygwin':
    # On Cygwin, os.path.normcase() lies, so just report back the
    # fact that the underlying Win32 OS is case-insensitive.
    def case_sensitive_suffixes(s1, s2):
        return 0
else:
    def case_sensitive_suffixes(s1, s2):
        return (os.path.normcase(s1) != os.path.normcase(s2))


file_expr = r"""File "[^"]*", line \d+, in [^\n]+
"""

# re.escape escapes too much.
def re_escape(str):
    for c in '\\.[]()*+?':   # Not an exhaustive list.
        str = str.replace(c, '\\' + c)
    return str

#
# Helper functions that we use as a replacement to the default re.match
# when searching for special strings in stdout/stderr.
#
def search_re(out, l):
    """ Search the regular expression 'l' in the output 'out'
        and return the start index when successful.
    """
    m = re.search(l, out)
    if m:
        return m.start()

    return None

def search_re_in_list(out, l):
    """ Search the regular expression 'l' in each line of
        the given string list 'out' and return the line's index
        when successful.
    """
    for idx, o in enumerate(out):
        m = re.search(l, o)
        if m:
            return idx

    return None

#
# Helpers for handling Python version numbers
#
def python_version_string():
    return sys.version.split()[0]

def python_minor_version_string():
    return sys.version[:3]

def unsupported_python_version(version=sys.version_info):
    return version < python_version_unsupported

def deprecated_python_version(version=sys.version_info):
    return version < python_version_deprecated

if deprecated_python_version():
    msg = r"""
scons: warning: Support for pre-2.7.0 Python version (%s) is deprecated.
    If this will cause hardship, contact scons-dev@scons.org
"""

    deprecated_python_expr = re_escape(msg % python_version_string()) + file_expr
    del msg
else:
    deprecated_python_expr = ""


def initialize_sconsflags(ignore_python_version):
    """
    Add the --warn=no-python-version option to SCONSFLAGS for every
    command so test scripts don't have to filter out Python version
    deprecation warnings.
    Same for --warn=no-visual-c-missing.
    """
    save_sconsflags = os.environ.get('SCONSFLAGS')
    if save_sconsflags:
        sconsflags = [save_sconsflags]
    else:
        sconsflags = []
    if ignore_python_version and deprecated_python_version():
        sconsflags.append('--warn=no-python-version')
    # Provide a way to suppress or provide alternate flags for
    # TestSCons purposes by setting TESTSCONS_SCONSFLAGS.
    # (The intended use case is to set it to null when running
    # timing tests of earlier versions of SCons which don't
    # support the --warn=no-visual-c-missing warning.)
    visual_c = os.environ.get('TESTSCONS_SCONSFLAGS',
                              '--warn=no-visual-c-missing')
    if visual_c:
        sconsflags.append(visual_c)
    os.environ['SCONSFLAGS'] = ' '.join(sconsflags)
    return save_sconsflags

def restore_sconsflags(sconsflags):
    if sconsflags is None:
        del os.environ['SCONSFLAGS']
    else:
        os.environ['SCONSFLAGS'] = sconsflags


class TestSCons(TestCommon):
    """Class for testing SCons.

    This provides a common place for initializing SCons tests,
    eliminating the need to begin every test with the same repeated
    initializations.
    """

    scons_version = SConsVersion
    javac_is_gcj = False

    def __init__(self, **kw):
        """Initialize an SCons testing object.

        If they're not overridden by keyword arguments, this
        initializes the object with the following default values:

                program = 'scons' if it exists,
                          else 'scons.py'
                interpreter = 'python'
                match = match_exact
                workdir = ''

        The workdir value means that, by default, a temporary workspace
        directory is created for a TestSCons environment.  In addition,
        this method changes directory (chdir) to the workspace directory,
        so an explicit "chdir = '.'" on all of the run() method calls
        is not necessary.
        """
        self.orig_cwd = os.getcwd()
        self.external = os.environ.get('SCONS_EXTERNAL_TEST', 0)

        if not self.external:
            try:
                script_dir = os.environ['SCONS_SCRIPT_DIR']
            except KeyError:
                pass
            else:
                os.chdir(script_dir)
        if 'program' not in kw:
            kw['program'] = os.environ.get('SCONS')
            if not kw['program']:
                if not self.external:
                    if os.path.exists('scons'):
                        kw['program'] = 'scons'
                    else:
                        kw['program'] = 'scons.py'
                else:
                    kw['program'] = 'scons'
                    kw['interpreter'] = ''
            elif not self.external and not os.path.isabs(kw['program']):
                kw['program'] = os.path.join(self.orig_cwd, kw['program'])
        if 'interpreter' not in kw and not os.environ.get('SCONS_EXEC'):
            kw['interpreter'] = [python,]
            if sys.version_info[0] < 3:
                kw['interpreter'].append('-tt')
        if 'match' not in kw:
            kw['match'] = match_exact
        if 'workdir' not in kw:
            kw['workdir'] = ''

        # Term causing test failures due to bogus readline init
        # control character output on FC8
        # TERM can cause test failures due to control chars in prompts etc.
        os.environ['TERM'] = 'dumb'

        self.ignore_python_version = kw.get('ignore_python_version', 1)
        if kw.get('ignore_python_version', -1) != -1:
            del kw['ignore_python_version']

        TestCommon.__init__(self, **kw)

        if not self.external:
            import SCons.Node.FS
            if SCons.Node.FS.default_fs is None:
                SCons.Node.FS.default_fs = SCons.Node.FS.FS()

        try:
            self.fixture_dirs = (os.environ['FIXTURE_DIRS']).split(os.pathsep)
        except KeyError:
            pass

    def Environment(self, ENV=None, *args, **kw):
        """
        Return a construction Environment that optionally overrides
        the default external environment with the specified ENV.
        """
        if not self.external:
            import SCons.Environment
            import SCons.Errors
            if not ENV is None:
                kw['ENV'] = ENV
            try:
                return SCons.Environment.Environment(*args, **kw)
            except (SCons.Errors.UserError, SCons.Errors.InternalError):
                return None

        return None

    def detect(self, var, prog=None, ENV=None, norm=None):
        """
        Return the detected path to a tool program.

        Searches first the named construction variable, then
        the SCons path.

        Args:
            var: name of construction variable to check for tool name.
            prog: tool program to check for.
            ENV: if present, kwargs to initialize an environment that
                will be created to perform the lookup.
            norm: if true, normalize any returned path looked up in
                the environment to use UNIX-style path separators.

        Returns: full path to the tool, or None.

        """
        env = self.Environment(ENV)
        if env:
            v = env.subst('$' + var)
            if not v:
                return None
            if prog is None:
                prog = v
            if v != prog:
                return None
            result = env.WhereIs(prog)
            if result and norm and os.sep != '/':
                result = result.replace(os.sep, '/')
            return result

        return self.where_is(prog)

    def detect_tool(self, tool, prog=None, ENV=None):
        """
        Given a tool (i.e., tool specification that would be passed
        to the "tools=" parameter of Environment()) and a program that
        corresponds to that tool, return true if and only if we can find
        that tool using Environment.Detect().

        By default, prog is set to the value passed into the tools parameter.
        """

        if not prog:
            prog = tool
        env = self.Environment(ENV, tools=[tool])
        if env is None:
            return None
        return env.Detect([prog])

    def where_is(self, prog, path=None, pathext=None):
        """
        Given a program, search for it in the specified external PATH,
        or in the actual external PATH if none is specified.
        """
        if path is None:
            path = os.environ['PATH']
        if self.external:
            if isinstance(prog, str):
                prog = [prog]
            for p in prog:
                result = TestCmd.where_is(self, p, path, pathext)
                if result:
                    return os.path.normpath(result)
        else:
            import SCons.Environment
            env = SCons.Environment.Environment()
            return env.WhereIs(prog, path, pathext)

        return None

    def wrap_stdout(self, build_str = "", read_str = "", error = 0, cleaning = 0):
        """Wraps standard output string(s) in the normal
        "Reading ... done" and "Building ... done" strings
        """
        cap,lc = [ ('Build','build'),
                   ('Clean','clean') ][cleaning]
        if error:
            term = "scons: %sing terminated because of errors.\n" % lc
        else:
            term = "scons: done %sing targets.\n" % lc
        return "scons: Reading SConscript files ...\n" + \
               read_str + \
               "scons: done reading SConscript files.\n" + \
               "scons: %sing targets ...\n" % cap + \
               build_str + \
               term

    def run(self, *args, **kw):
        """
        Set up SCONSFLAGS for every command so test scripts don't need
        to worry about unexpected warnings in their output.
        """
        sconsflags = initialize_sconsflags(self.ignore_python_version)
        try:
            TestCommon.run(self, *args, **kw)
        finally:
            restore_sconsflags(sconsflags)

# Modifying the options should work and ought to be simpler, but this
# class is used for more than just running 'scons' itself.  If there's
# an automated  way of determining whether it's running 'scons' or
# something else, this code should be resurected.
#        options = kw.get('options')
#        if options:
#            options = [options]
#        else:
#            options = []
#        if self.ignore_python_version and deprecated_python_version():
#            options.append('--warn=no-python-version')
#        # Provide a way to suppress or provide alternate flags for
#        # TestSCons purposes by setting TESTSCONS_SCONSFLAGS.
#        # (The intended use case is to set it to null when running
#        # timing tests of earlier versions of SCons which don't
#        # support the --warn=no-visual-c-missing warning.)
#        visual_c = os.environ.get('TESTSCONS_SCONSFLAGS',
#                                      '--warn=no-visual-c-missing')
#        if visual_c:
#            options.append(visual_c)
#        kw['options'] = ' '.join(options)
#        TestCommon.run(self, *args, **kw)

    def up_to_date(self, arguments = '.', read_str = "", **kw):
        """Asserts that all of the targets listed in arguments is
        up to date, but does not make any assumptions on other targets.
        This function is most useful in conjunction with the -n option.
        """
        s = ""
        for arg in arguments.split():
            s = s + "scons: `%s' is up to date.\n" % arg
        kw['arguments'] = arguments
        stdout = self.wrap_stdout(read_str = read_str, build_str = s)
        # Append '.*' so that timing output that comes after the
        # up-to-date output is okay.
        kw['stdout'] = re.escape(stdout) + '.*'
        kw['match'] = self.match_re_dotall
        self.run(**kw)

    def not_up_to_date(self, arguments = '.', **kw):
        """Asserts that none of the targets listed in arguments is
        up to date, but does not make any assumptions on other targets.
        This function is most useful in conjunction with the -n option.
        """
        s = ""
        for arg in arguments.split():
            s = s + "(?!scons: `%s' is up to date.)" % re.escape(arg)
        s = '('+s+'[^\n]*\n)*'
        kw['arguments'] = arguments
        stdout = re.escape(self.wrap_stdout(build_str='ARGUMENTSGOHERE'))
        kw['stdout'] = stdout.replace('ARGUMENTSGOHERE', s)
        kw['match'] = self.match_re_dotall
        self.run(**kw)

    def option_not_yet_implemented(self, option, arguments=None, **kw):
        """
        Verifies expected behavior for options that are not yet implemented:
        a warning message, and exit status 1.
        """
        msg = "Warning:  the %s option is not yet implemented\n" % option
        kw['stderr'] = msg
        if arguments:
            # If it's a long option and the argument string begins with '=',
            # it's of the form --foo=bar and needs no separating space.
            if option[:2] == '--' and arguments[0] == '=':
                kw['arguments'] = option + arguments
            else:
                kw['arguments'] = option + ' ' + arguments
        return self.run(**kw)

    def deprecated_wrap(self, msg):
        """
        Calculate the pattern that matches a deprecation warning.
        """
        return '\nscons: warning: ' + re_escape(msg) + '\n' + file_expr

    def deprecated_fatal(self, warn, msg):
        """
        Determines if the warning has turned into a fatal error.  If so,
        passes the test, as any remaining runs are now moot.

        This method expects a SConscript to be present that will causes
        the warning.  The method writes a SConstruct that calls the
        SConsscript and looks to see what type of result occurs.

        The pattern that matches the warning is returned.

        TODO: Actually detect that it's now an error.  We don't have any
        cases yet, so there's no way to test it.
        """
        self.write('SConstruct', """if True:
            WARN = ARGUMENTS.get('WARN')
            if WARN: SetOption('warn', WARN)
            SConscript('SConscript')
        """)

        def err_out():
            # TODO calculate stderr for fatal error
            return re_escape('put something here')

        # no option, should get one of nothing, warning, or error
        warning = self.deprecated_wrap(msg)
        self.run(arguments = '.', stderr = None)
        stderr = self.stderr()
        if stderr:
            # most common case done first
            if match_re_dotall(stderr, warning):
               # expected output
               pass
            elif match_re_dotall(stderr, err_out()):
               # now a fatal error; skip the rest of the tests
               self.pass_test()
            else:
               # test failed; have to do this by hand...
               print(self.banner('STDOUT '))
               print(self.stdout())
               print(self.diff(warning, stderr, 'STDERR '))
               self.fail_test()

        return warning

    def deprecated_warning(self, warn, msg):
        """
        Verifies the expected behavior occurs for deprecation warnings.
        This method expects a SConscript to be present that will causes
        the warning.  The method writes a SConstruct and exercises various
        combinations of command-line options and SetOption parameters to
        validate that it performs correctly.

        The pattern that matches the warning is returned.
        """
        warning = self.deprecated_fatal(warn, msg)

        def RunPair(option, expected):
            # run the same test with the option on the command line and
            # then with the option passed via SetOption().
            self.run(options = '--warn=' + option,
                     arguments = '.',
                     stderr = expected,
                     match = match_re_dotall)
            self.run(options = 'WARN=' + option,
                     arguments = '.',
                     stderr = expected,
                     match = match_re_dotall)

        # all warnings off, should get no output
        RunPair('no-deprecated', '')

        # warning enabled, should get expected output
        RunPair(warn, warning)

        # warning disabled, should get either nothing or mandatory message
        expect = """()|(Can not disable mandataory warning: 'no-%s'\n\n%s)""" % (warn, warning)
        RunPair('no-' + warn, expect)

        return warning

    def diff_substr(self, expect, actual, prelen=20, postlen=40):
        i = 0
        for x, y in zip(expect, actual):
            if x != y:
                return "Actual did not match expect at char %d:\n" \
                       "    Expect:  %s\n" \
                       "    Actual:  %s\n" \
                       % (i, repr(expect[i-prelen:i+postlen]),
                             repr(actual[i-prelen:i+postlen]))
            i = i + 1
        return "Actual matched the expected output???"

    def python_file_line(self, file, line):
        """
        Returns a Python error line for output comparisons.

        The exec of the traceback line gives us the correct format for
        this version of Python.

            File "<string>", line 1, <module>

        We stick the requested file name and line number in the right
        places, abstracting out the version difference.
        """
        # This routine used to use traceback to get the proper format
        # that doesn't work well with py3. And the format of the
        # traceback seems to be stable, so let's just format
        # an appropriate string
        #
        #exec('import traceback; x = traceback.format_stack()[-1]')
        #       import traceback
        #       x = traceback.format_stack()
        #        x = # XXX: .lstrip()
        #       x = x.replace('<string>', file)
        #      x = x.replace('line 1,', 'line %s,' % line)
        #      x="\n".join(x)
        x='File "%s", line %s, in <module>\n'%(file,line)
        return x

    def normalize_ps(self, s):
        s = re.sub(r'(Creation|Mod)Date: .*',
                   r'\1Date XXXX', s)
        s = re.sub(r'%DVIPSSource:\s+TeX output\s.*',
                   r'%DVIPSSource:   TeX output XXXX', s)
        s = re.sub(r'/(BaseFont|FontName) /[A-Z0-9]{6}',
                   r'/\1 /XXXXXX', s)
        s = re.sub(r'BeginFont: [A-Z0-9]{6}',
                   r'BeginFont: XXXXXX', s)

        return s

    @staticmethod
    def to_bytes_re_sub(pattern, repl, str, count=0, flags=0):
        """
        Wrapper around re.sub to change pattern and repl to bytes to work with
        both python 2 & 3
        """
        pattern = to_bytes(pattern)
        repl = to_bytes(repl)
        return re.sub(pattern, repl, str, count, flags)

    def normalize_pdf(self, s):
        s = self.to_bytes_re_sub(r'/(Creation|Mod)Date \(D:[^)]*\)',
                       r'/\1Date (D:XXXX)', s)
        s = self.to_bytes_re_sub(r'/ID \[<[0-9a-fA-F]*> <[0-9a-fA-F]*>\]',
                       r'/ID [<XXXX> <XXXX>]', s)
        s = self.to_bytes_re_sub(r'/(BaseFont|FontName) /[A-Z]{6}',
                       r'/\1 /XXXXXX', s)
        s = self.to_bytes_re_sub(r'/Length \d+ *\n/Filter /FlateDecode\n',
                       r'/Length XXXX\n/Filter /FlateDecode\n', s)

        try:
            import zlib
        except ImportError:
            pass
        else:
            begin_marker = to_bytes('/FlateDecode\n>>\nstream\n')
            end_marker = to_bytes('endstream\nendobj')

            encoded = []
            b = s.find(begin_marker, 0)
            while b != -1:
                b = b + len(begin_marker)
                e = s.find(end_marker, b)
                encoded.append((b, e))
                b = s.find(begin_marker, e + len(end_marker))

            x = 0
            r = []
            for b, e in encoded:
                r.append(s[x:b])
                d = zlib.decompress(s[b:e])
                d = self.to_bytes_re_sub(r'%%CreationDate: [^\n]*\n',
                               r'%%CreationDate: 1970 Jan 01 00:00:00\n', d)
                d = self.to_bytes_re_sub(r'%DVIPSSource:  TeX output \d\d\d\d\.\d\d\.\d\d:\d\d\d\d',
                               r'%DVIPSSource:  TeX output 1970.01.01:0000', d)
                d = self.to_bytes_re_sub(r'/(BaseFont|FontName) /[A-Z]{6}',
                               r'/\1 /XXXXXX', d)
                r.append(d)
                x = e
            r.append(s[x:])
            s = to_bytes('').join(r)

        return s

    def paths(self,patterns):
        import glob
        result = []
        for p in patterns:
            result.extend(sorted(glob.glob(p)))
        return result

    def unlink_sconsignfile(self,name='.sconsign.dblite'):
        """
        Delete sconsign file.
        Note on python it seems to append .p3 to the file name so we take care of that
        Parameters
        ----------
        name - expected name of sconsign file

        Returns
        -------
        None
        """
        if sys.version_info[0] == 3:
            name += '.p3'
        self.unlink(name)

    def java_ENV(self, version=None):
        """
        Initialize with a default external environment that uses a local
        Java SDK in preference to whatever's found in the default PATH.

        :param version: if set, match only that version
        :return: the new env.
        """
        if not self.external:
            try:
                return self._java_env[version]['ENV']
            except AttributeError:
                self._java_env = {}
            except KeyError:
                pass

            import SCons.Environment
            env = SCons.Environment.Environment()
            self._java_env[version] = env

            if version:
                if sys.platform == 'win32':
                    patterns = [
                        'C:/Program Files*/Java/jdk*%s*/bin' % version,
                    ]
                else:
                    patterns = [
                        '/usr/java/jdk%s*/bin' % version,
                        '/usr/lib/jvm/*-%s*/bin' % version,
                        '/usr/local/j2sdk%s*/bin' % version,
                    ]
                java_path = self.paths(patterns) + [env['ENV']['PATH']]
            else:
                if sys.platform == 'win32':
                    patterns = [
                        'C:/Program Files*/Java/jdk*/bin',
                    ]
                else:
                    patterns = [
                        '/usr/java/latest/bin',
                        '/usr/lib/jvm/*/bin',
                        '/usr/local/j2sdk*/bin',
                    ]
                java_path = self.paths(patterns) + [env['ENV']['PATH']]

            env['ENV']['PATH'] = os.pathsep.join(java_path)
            return env['ENV']

        return None

    def java_where_includes(self,version=None):
        """
        Find include path needed for compiling java jni code.

        :param version: if set, match only that version
        :return: path to java headers
        """
        import sys

        result = []
        if sys.platform[:6] == 'darwin':
            java_home = self.java_where_java_home(version)
            jni_path = os.path.join(java_home,'include','jni.h')
            if os.path.exists(jni_path):
                result.append(os.path.dirname(jni_path))

        if not version:
            version=''
            jni_dirs = ['/System/Library/Frameworks/JavaVM.framework/Headers/jni.h',
                        '/usr/lib/jvm/default-java/include/jni.h',
                        '/usr/lib/jvm/java-*-oracle/include/jni.h']
        else:
            jni_dirs = ['/System/Library/Frameworks/JavaVM.framework/Versions/%s*/Headers/jni.h'%version]
        jni_dirs.extend(['/usr/lib/jvm/java-*-sun-%s*/include/jni.h'%version,
                         '/usr/lib/jvm/java-%s*-openjdk*/include/jni.h'%version,
                         '/usr/java/jdk%s*/include/jni.h'%version])
        dirs = self.paths(jni_dirs)
        if not dirs:
            return None
        d=os.path.dirname(self.paths(jni_dirs)[0])
        result.append(d)

        if sys.platform == 'win32':
            result.append(os.path.join(d,'win32'))
        elif sys.platform.startswith('linux'):
            result.append(os.path.join(d,'linux'))
        return result

    def java_where_java_home(self, version=None):
        """
        Find path to what would be JAVA_HOME.

        SCons does not read JAVA_HOME from the environment, so deduce it.

        :param version: if set, match only that version
        :return: path where JDK components live
        """
        if sys.platform[:6] == 'darwin':
            # osx 10.11, 10.12
            home_tool = '/usr/libexec/java_home'
            java_home = False
            if os.path.exists(home_tool):
                java_home = subprocess.check_output(home_tool).strip()
                java_home = java_home.decode()

            if version is None:
                if java_home:
                    return java_home
                else:
                    homes = ['/System/Library/Frameworks/JavaVM.framework/Home',
                            # osx 10.10
                             '/System/Library/Frameworks/JavaVM.framework/Versions/Current/Home']
                    for home in homes:
                        if os.path.exists(home):
                            return home

            else:
                if java_home.find('jdk%s'%version) != -1:
                    return java_home
                else:
                    home = '/System/Library/Frameworks/JavaVM.framework/Versions/%s/Home' % version
                    if not os.path.exists(home):
                        # This works on OSX 10.10
                        home = '/System/Library/Frameworks/JavaVM.framework/Versions/Current/'
        else:
            jar = self.java_where_jar(version)
            home = os.path.normpath('%s/..'%jar)
        if os.path.isdir(home):
            return home
        print("Could not determine JAVA_HOME: %s is not a directory" % home)
        self.fail_test()

    def java_mac_check(self, where_java_bin, java_bin_name):
        # on Mac there is a place holder java installed to start the java install process
        # so we need to check the output in this case, more info here:
        # http://anas.pk/2015/09/02/solution-no-java-runtime-present-mac-yosemite/
        sp = subprocess.Popen([where_java_bin, "-version"], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        stdout, stderr = sp.communicate()
        sp.wait()
        if("No Java runtime" in str(stderr)):
            self.skip_test("Could not find Java " + java_bin_name + ", skipping test(s).\n")

    def java_where_jar(self, version=None):
        """
        Find java archiver jar.

        :param version: if set, match only that version
        :return: path to jar
        """
        ENV = self.java_ENV(version)
        if self.detect_tool('jar', ENV=ENV):
            where_jar = self.detect('JAR', 'jar', ENV=ENV)
        else:
            where_jar = self.where_is('jar', ENV['PATH'])
        if not where_jar:
            self.skip_test("Could not find Java jar, skipping test(s).\n")
        elif sys.platform == "darwin":
            self.java_mac_check(where_jar, 'jar')

        return where_jar

    def java_where_java(self, version=None):
        """
        Find java executable.

        :param version: if set, match only that version
        :return: path to the java rutime
        """
        ENV = self.java_ENV(version)
        where_java = self.where_is('java', ENV['PATH'])

        if not where_java:
            self.skip_test("Could not find Java java, skipping test(s).\n")
        elif sys.platform == "darwin":
            self.java_mac_check(where_java, 'java')

        return where_java

    def java_where_javac(self, version=None):
        """
        Find java compiler.

        :param version: if set, match only that version
        :return: path to javac
        """
        ENV = self.java_ENV(version)
        if self.detect_tool('javac'):
            where_javac = self.detect('JAVAC', 'javac', ENV=ENV)
        else:
            where_javac = self.where_is('javac', ENV['PATH'])
        if not where_javac:
            self.skip_test("Could not find Java javac, skipping test(s).\n")
        elif sys.platform == "darwin":
            self.java_mac_check(where_javac, 'javac')

        self.run(program = where_javac,
                 arguments = '-version',
                 stderr=None,
                 status=None)
        # Note recent versions output version info to stdout instead of stderr
        if version:
            verf = 'javac %s' % version
            if self.stderr().find(verf) == -1 and self.stdout().find(verf) == -1:
                fmt = "Could not find javac for Java version %s, skipping test(s).\n"
                self.skip_test(fmt % version)
        else:
            version_re = r'javac (\d*\.*\d)'
            m = re.search(version_re, self.stderr())
            if not m:
                m = re.search(version_re, self.stdout())

            if m:
                version = m.group(1)
                self.javac_is_gcj = False
            elif self.stderr().find('gcj') != -1:
                version='1.2'
                self.javac_is_gcj = True
            else:
                version = None
                self.javac_is_gcj = False
        return where_javac, version

    def java_where_javah(self, version=None):
        """
        Find java header generation tool.

        TODO issue #3347 since JDK10, there is no separate javah command,
        'javac -h' is used. We should not return a javah from a different
        installed JDK - how to detect and what to return in this case?

        :param version: if set, match only that version
        :return: path to javah
        """
        ENV = self.java_ENV(version)
        if self.detect_tool('javah'):
            where_javah = self.detect('JAVAH', 'javah', ENV=ENV)
        else:
            where_javah = self.where_is('javah', ENV['PATH'])
        if not where_javah:
            self.skip_test("Could not find Java javah, skipping test(s).\n")
        return where_javah

    def java_where_rmic(self, version=None):
        """
        Find java rmic tool.

        :param version: if set, match only that version
        :return: path to rmic
        """
        ENV = self.java_ENV(version)
        if self.detect_tool('rmic'):
            where_rmic = self.detect('RMIC', 'rmic', ENV=ENV)
        else:
            where_rmic = self.where_is('rmic', ENV['PATH'])
        if not where_rmic:
            self.skip_test("Could not find Java rmic, skipping non-simulated test(s).\n")
        return where_rmic


    def java_get_class_files(self, dir):
        result = []
        for dirpath, dirnames, filenames in os.walk(dir):
            for fname in filenames:
                if fname.endswith('.class'):
                    result.append(os.path.join(dirpath, fname))
        return sorted(result)


    def Qt_dummy_installation(self, dir='qt'):
        # create a dummy qt installation

        self.subdir(dir, [dir, 'bin'], [dir, 'include'], [dir, 'lib'])

        self.write([dir, 'bin', 'mymoc.py'], """\
import getopt
import sys
import re
# -w and -z are fake options used in test/QT/QTFLAGS.py
cmd_opts, args = getopt.getopt(sys.argv[1:], 'io:wz', [])
impl = 0
opt_string = ''
for opt, arg in cmd_opts:
    if opt == '-o': outfile = arg
    elif opt == '-i': impl = 1
    else: opt_string = opt_string + ' ' + opt

with open(outfile, 'w') as ofp:
    ofp.write("/* mymoc.py%s */\\n" % opt_string)
    for a in args:
        with open(a, 'r') as ifp:
            contents = ifp.read()
        a = a.replace('\\\\', '\\\\\\\\')
        subst = r'{ my_qt_symbol( "' + a + '\\\\n" ); }'
        if impl:
            contents = re.sub(r'#include.*', '', contents)
        ofp.write(contents.replace('Q_OBJECT', subst))
sys.exit(0)
""")

        self.write([dir, 'bin', 'myuic.py'], """\
import os.path
import re
import sys
output_arg = 0
impl_arg = 0
impl = None
source = None
opt_string = ''
for arg in sys.argv[1:]:
    if output_arg:
        outfile = arg
        output_arg = 0
    elif impl_arg:
        impl = arg
        impl_arg = 0
    elif arg == "-o":
        output_arg = 1
    elif arg == "-impl":
        impl_arg = 1
    elif arg[0:1] == "-":
        opt_string = opt_string + ' ' + arg
    else:
        if source:
            sys.exit(1)
        source = sourceFile = arg

with open(outfile, 'w') as ofp, open(source, 'r') as ifp:
    ofp.write("/* myuic.py%s */\\n" % opt_string)
    if impl:
        ofp.write('#include "' + impl + '"\\n')
        includes = re.findall('<include.*?>(.*?)</include>', ifp.read())
        for incFile in includes:
            # this is valid for ui.h files, at least
            if os.path.exists(incFile):
                ofp.write('#include "' + incFile + '"\\n')
    else:
        ofp.write('#include "my_qobject.h"\\n' + ifp.read() + " Q_OBJECT \\n")
sys.exit(0)
""" )

        self.write([dir, 'include', 'my_qobject.h'], r"""
#define Q_OBJECT ;
void my_qt_symbol(const char *arg);
""")

        self.write([dir, 'lib', 'my_qobject.cpp'], r"""
#include "../include/my_qobject.h"
#include <stdio.h>
void my_qt_symbol(const char *arg) {
  fputs(arg, stdout);
}
""")

        self.write([dir, 'lib', 'SConstruct'], r"""
env = Environment()
import sys
if sys.platform == 'win32':
    env.StaticLibrary('myqt', 'my_qobject.cpp')
else:
    env.SharedLibrary('myqt', 'my_qobject.cpp')
""")

        self.run(chdir = self.workpath(dir, 'lib'),
                 arguments = '.',
                 stderr = noisy_ar,
                 match = self.match_re_dotall)

        self.QT = self.workpath(dir)
        self.QT_LIB = 'myqt'
        self.QT_MOC = '%s %s' % (_python_, self.workpath(dir, 'bin', 'mymoc.py'))
        self.QT_UIC = '%s %s' % (_python_, self.workpath(dir, 'bin', 'myuic.py'))
        self.QT_LIB_DIR = self.workpath(dir, 'lib')

    def Qt_create_SConstruct(self, place):
        if isinstance(place, list):
            place = test.workpath(*place)
        self.write(place, """\
if ARGUMENTS.get('noqtdir', 0): QTDIR=None
else: QTDIR=r'%s'
env = Environment(QTDIR = QTDIR,
                  QT_LIB = r'%s',
                  QT_MOC = r'%s',
                  QT_UIC = r'%s',
                  tools=['default','qt'])
dup = 1
if ARGUMENTS.get('variant_dir', 0):
    if ARGUMENTS.get('chdir', 0):
        SConscriptChdir(1)
    else:
        SConscriptChdir(0)
    dup=int(ARGUMENTS.get('dup', 1))
    if dup == 0:
        builddir = 'build_dup0'
        env['QT_DEBUG'] = 1
    else:
        builddir = 'build'
    VariantDir(builddir, '.', duplicate=dup)
    print(builddir, dup)
    sconscript = Dir(builddir).File('SConscript')
else:
    sconscript = File('SConscript')
Export("env dup")
SConscript(sconscript)
""" % (self.QT, self.QT_LIB, self.QT_MOC, self.QT_UIC))


    NCR = 0 # non-cached rebuild
    CR  = 1 # cached rebuild (up to date)
    NCF = 2 # non-cached build failure
    CF  = 3 # cached build failure

    if sys.platform == 'win32':
        Configure_lib = 'msvcrt'
    else:
        Configure_lib = 'm'

    # to use cygwin compilers on cmd.exe -> uncomment following line
    #Configure_lib = 'm'

    def coverage_run(self):
        """ Check if the the tests are being run under coverage.
        """
        return 'COVERAGE_PROCESS_START' in os.environ or 'COVERAGE_FILE' in os.environ

    def skip_if_not_msvc(self, check_platform=True):
        """ Check whether we are on a Windows platform and skip the
            test if not. This check can be omitted by setting
            check_platform to False.
            Then, for a win32 platform, additionally check
            whether we have a MSVC toolchain installed
            in the system, and skip the test if none can be
            found (=MinGW is the only compiler available).
        """
        if check_platform:
            if sys.platform != 'win32':
                msg = "Skipping Visual C/C++ test on non-Windows platform '%s'\n" % sys.platform
                self.skip_test(msg)
                return

        try:
            import SCons.Tool.MSCommon as msc
            if not msc.msvc_exists():
                msg = "No MSVC toolchain found...skipping test\n"
                self.skip_test(msg)
        except:
            pass

    def checkLogAndStdout(self, checks, results, cached,
                          logfile, sconf_dir, sconstruct,
                          doCheckLog=True, doCheckStdout=True):
        """
        Used to verify the expected output from using Configure()
        via the contents of one or both of stdout or config.log file.
        The checks, results, cached parameters all are zipped together
        for use in comparing results.

        TODO: Perhaps a better API makes sense?

        Parameters
        ----------
        checks : The Configure checks being run

        results : The expected results for each check

        cached  : If the corresponding check is expected to be cached

        logfile : Name of the config log

        sconf_dir : Name of the sconf dir

        sconstruct : SConstruct file name

        doCheckLog : check specified log file, defaults to true

        doCheckStdout : Check stdout, defaults to true

        Returns
        -------

        """

        class NoMatch(Exception):
            def __init__(self, p):
                self.pos = p

        def matchPart(log, logfile, lastEnd, NoMatch=NoMatch):
            """
            Match part of the logfile
            """
            m = re.match(log, logfile[lastEnd:])
            if not m:
                raise NoMatch(lastEnd)
            return m.end() + lastEnd

        try:

            # Build regexp for a character which is not
            # a linesep, and in the case of CR/LF
            # build it with both CR and CR/LF
            # TODO: Not sure why this is a good idea. A static string
            #       could do the same since we only have two variations
            #       to do with?
            # ls = os.linesep
            # nols = "("
            # for i in range(len(ls)):
            #     nols = nols + "("
            #     for j in range(i):
            #         nols = nols + ls[j]
            #     nols = nols + "[^" + ls[i] + "])"
            #     if i < len(ls)-1:
            #         nols = nols + "|"
            # nols = nols + ")"
            #
            # Replaced above logic with \n as we're reading the file
            # using non-binary read. Python will translate \r\n -> \n
            # For us.
            ls = '\n'
            nols = '([^\n])'
            lastEnd = 0

            # Read the whole logfile
            logfile = self.read(self.workpath(logfile), mode='r')

            # Some debug code to keep around..
            # sys.stderr.write("LOGFILE[%s]:%s"%(type(logfile),logfile))

            if (doCheckLog and
                logfile.find("scons: warning: The stored build information has an unexpected class.") >= 0):
                self.fail_test()

            sconf_dir = sconf_dir
            sconstruct = sconstruct

            log = r'file\ \S*%s\,line \d+:' % re.escape(sconstruct) + ls
            if doCheckLog:
                lastEnd = matchPart(log, logfile, lastEnd)

            log = "\t" + re.escape("Configure(confdir = %s)" % sconf_dir) + ls
            if doCheckLog:
                lastEnd = matchPart(log, logfile, lastEnd)

            rdstr = ""
            cnt = 0
            for check,result,cache_desc in zip(checks, results, cached):
                log   = re.escape("scons: Configure: " + check) + ls

                if doCheckLog:
                    lastEnd = matchPart(log, logfile, lastEnd)

                log = ""
                result_cached = 1
                for bld_desc in cache_desc: # each TryXXX
                    for ext, flag in bld_desc: # each file in TryBuild
                        file = os.path.join(sconf_dir,"conftest_%d%s" % (cnt, ext))
                        if flag == self.NCR:
                            # NCR = Non Cached Rebuild
                            # rebuild will pass
                            if ext in ['.c', '.cpp']:
                                log=log + re.escape(file + " <-") + ls
                                log=log + r"(  \|" + nols + "*" + ls + ")+?"
                            else:
                                log=log + "(" + nols + "*" + ls +")*?"
                            result_cached = 0
                        if flag == self.CR:
                            # CR = cached rebuild (up to date)s
                            # up to date
                            log=log + \
                                 re.escape("scons: Configure: \"%s\" is up to date."
                                           % file) + ls
                            log=log+re.escape("scons: Configure: The original builder "
                                              "output was:") + ls
                            log=log+r"(  \|.*"+ls+")+"
                        if flag == self.NCF:
                            # non-cached rebuild failure
                            log=log + "(" + nols + "*" + ls + ")*?"
                            result_cached = 0
                        if flag == self.CF:
                            # cached rebuild failure
                            log=log + \
                                 re.escape("scons: Configure: Building \"%s\" failed "
                                           "in a previous run and all its sources are"
                                           " up to date." % file) + ls
                            log=log+re.escape("scons: Configure: The original builder "
                                              "output was:") + ls
                            log=log+r"(  \|.*"+ls+")+"
                    cnt = cnt + 1
                if result_cached:
                    result = "(cached) " + result
                rdstr = rdstr + re.escape(check) + re.escape(result) + "\n"
                log=log + re.escape("scons: Configure: " + result) + ls + ls

                if doCheckLog:
                    lastEnd = matchPart(log, logfile, lastEnd)

                log = ""
            if doCheckLog: lastEnd = matchPart(ls, logfile, lastEnd)
            if doCheckLog and lastEnd != len(logfile):
                raise NoMatch(lastEnd)

        except NoMatch as m:
            print("Cannot match log file against log regexp.")
            print("log file: ")
            print("------------------------------------------------------")
            print(logfile[m.pos:])
            print("------------------------------------------------------")
            print("log regexp: ")
            print("------------------------------------------------------")
            print(log)
            print("------------------------------------------------------")
            self.fail_test()

        if doCheckStdout:
            exp_stdout = self.wrap_stdout(".*", rdstr)
            if not self.match_re_dotall(self.stdout(), exp_stdout):
                print("Unexpected stdout: ")
                print("-----------------------------------------------------")
                print(repr(self.stdout()))
                print("-----------------------------------------------------")
                print(repr(exp_stdout))
                print("-----------------------------------------------------")
                self.fail_test()

    def get_python_version(self):
        """
        Returns the Python version (just so everyone doesn't have to
        hand-code slicing the right number of characters).
        """
        # see also sys.prefix documentation
        return python_minor_version_string()

    def get_platform_python_info(self, python_h_required=False):
        """
        Returns a path to a Python executable suitable for testing on
        this platform and its associated include path, library path and
        library name.

        If the Python executable or Python header (if required)
        is not found, the test is skipped.

        Returns a tuple:
            (path to python, include path, library path, library name)
        """
        python = os.environ.get('python_executable', self.where_is('python'))
        if not python:
            self.skip_test('Can not find installed "python", skipping test.\n')

        # construct a program to run in the intended environment
        # in order to fetch the characteristics of that Python.
        # Windows Python doesn't store all the info in config vars.
        if sys.platform == 'win32':
            self.run(program=python, stdin="""\
import sysconfig, sys, os.path
py_ver = 'python%d%d' % sys.version_info[:2]
# use distutils to help find include and lib path
# TODO: PY3 fine to use sysconfig.get_config_var("INCLUDEPY")
try:
    import distutils.sysconfig
    exec_prefix = distutils.sysconfig.EXEC_PREFIX
    include = distutils.sysconfig.get_python_inc()
    print(include)
    lib_path = os.path.join(exec_prefix, 'libs')
    if not os.path.exists(lib_path):
        # check for virtualenv path.
        # this might not build anything different than first try.
        def venv_path():
            if hasattr(sys, 'real_prefix'):
                return sys.real_prefix
            if hasattr(sys, 'base_prefix'):
                return sys.base_prefix
        lib_path = os.path.join(venv_path(), 'libs')
    if not os.path.exists(lib_path):
        # not clear this is useful: 'lib' does not contain linkable libs
        lib_path = os.path.join(exec_prefix, 'lib')
    print(lib_path)
except:
    include = os.path.join(sys.prefix, 'include', py_ver)
    print(include)
    lib_path = os.path.join(sys.prefix, 'lib', py_ver, 'config')
    print(lib_path)
print(py_ver)
Python_h = os.path.join(include, "Python.h")
if os.path.exists(Python_h):
    print(Python_h)
else:
    print("False")
""")
        else:
            self.run(program=python, stdin="""\
import sys, sysconfig, os.path
include = sysconfig.get_config_var("INCLUDEPY")
print(include)
print(sysconfig.get_config_var("LIBDIR"))
py_library_ver = sysconfig.get_config_var("LDVERSION")
if not py_library_ver:
    py_library_ver = '%d.%d' % sys.version_info[:2]
print("python"+py_library_ver)
Python_h = os.path.join(include, "Python.h")
if os.path.exists(Python_h):
    print(Python_h)
else:
    print("False")
""")
        incpath, libpath, libname, python_h = self.stdout().strip().split('\n')
        if python_h == "False" and python_h_required:
            self.skip_test('Can not find required "Python.h", skipping test.\n')

        return (python, incpath, libpath, libname)

    def start(self, *args, **kw):
        """
        Starts SCons in the test environment.

        This method exists to tell Test{Cmd,Common} that we're going to
        use standard input without forcing every .start() call in the
        individual tests to do so explicitly.
        """
        if 'stdin' not in kw:
            kw['stdin'] = True
        sconsflags = initialize_sconsflags(self.ignore_python_version)
        try:
            p = TestCommon.start(self, *args, **kw)
        finally:
            restore_sconsflags(sconsflags)
        return p

    def wait_for(self, fname, timeout=20.0, popen=None):
        """
        Waits for the specified file name to exist.
        """
        waited = 0.0
        while not os.path.exists(fname):
            if timeout and waited >= timeout:
                sys.stderr.write('timed out waiting for %s to exist\n' % fname)
                if popen:
                    popen.stdin.close()
                    popen.stdin = None
                    self.status = 1
                    self.finish(popen)
                stdout = self.stdout()
                if stdout:
                    sys.stdout.write(self.banner('STDOUT ') + '\n')
                    sys.stdout.write(stdout)
                stderr = self.stderr()
                if stderr:
                    sys.stderr.write(self.banner('STDERR ') + '\n')
                    sys.stderr.write(stderr)
                self.fail_test()
            time.sleep(1.0)
            waited = waited + 1.0

    def get_alt_cpp_suffix(self):
        """
        Many CXX tests have this same logic.
        They all needed to determine if the current os supports
        files with .C and .c as different files or not
        in which case they are instructed to use .cpp instead of .C
        """
        if not case_sensitive_suffixes('.c','.C'):
            alt_cpp_suffix = '.cpp'
        else:
            alt_cpp_suffix = '.C'
        return alt_cpp_suffix

    def platform_has_symlink(self):
        if not hasattr(os, 'symlink') or sys.platform == 'win32':
            return False
        else:
            return True


class Stat:
    def __init__(self, name, units, expression, convert=None):
        if convert is None:
            convert = lambda x: x
        self.name = name
        self.units = units
        self.expression = re.compile(expression)
        self.convert = convert

StatList = [
    Stat('memory-initial', 'kbytes',
         r'Memory before reading SConscript files:\s+(\d+)',
         convert=lambda s: int(s) // 1024),
    Stat('memory-prebuild', 'kbytes',
         r'Memory before building targets:\s+(\d+)',
         convert=lambda s: int(s) // 1024),
    Stat('memory-final', 'kbytes',
         r'Memory after building targets:\s+(\d+)',
         convert=lambda s: int(s) // 1024),

    Stat('time-sconscript', 'seconds',
         r'Total SConscript file execution time:\s+([\d.]+) seconds'),
    Stat('time-scons', 'seconds',
         r'Total SCons execution time:\s+([\d.]+) seconds'),
    Stat('time-commands', 'seconds',
         r'Total command execution time:\s+([\d.]+) seconds'),
    Stat('time-total', 'seconds',
         r'Total build time:\s+([\d.]+) seconds'),
]


class TimeSCons(TestSCons):
    """Class for timing SCons."""
    def __init__(self, *args, **kw):
        """
        In addition to normal TestSCons.TestSCons intialization,
        this enables verbose mode (which causes the command lines to
        be displayed in the output) and copies the contents of the
        directory containing the executing script to the temporary
        working directory.
        """
        self.variables = kw.get('variables')
        default_calibrate_variables = []
        if self.variables is not None:
            for variable, value in self.variables.items():
                value = os.environ.get(variable, value)
                try:
                    value = int(value)
                except ValueError:
                    try:
                        value = float(value)
                    except ValueError:
                        pass
                    else:
                        default_calibrate_variables.append(variable)
                else:
                    default_calibrate_variables.append(variable)
                self.variables[variable] = value
            del kw['variables']
        calibrate_keyword_arg = kw.get('calibrate')
        if calibrate_keyword_arg is None:
            self.calibrate_variables = default_calibrate_variables
        else:
            self.calibrate_variables = calibrate_keyword_arg
            del kw['calibrate']

        self.calibrate = os.environ.get('TIMESCONS_CALIBRATE', '0') != '0'

        if 'verbose' not in kw and not self.calibrate:
            kw['verbose'] = True

        TestSCons.__init__(self, *args, **kw)

        # TODO(sgk):    better way to get the script dir than sys.argv[0]
        self.test_dir = os.path.dirname(sys.argv[0])
        test_name = os.path.basename(self.test_dir)

        if not os.path.isabs(self.test_dir):
            self.test_dir = os.path.join(self.orig_cwd, self.test_dir)
        self.copy_timing_configuration(self.test_dir, self.workpath())

    def main(self, *args, **kw):
        """
        The main entry point for standard execution of timings.

        This method run SCons three times:

          Once with the --help option, to have it exit after just reading
          the configuration.

          Once as a full build of all targets.

          Once again as a (presumably) null or up-to-date build of
          all targets.

        The elapsed time to execute each build is printed after
        it has finished.
        """
        if 'options' not in kw and self.variables:
            options = []
            for variable, value in self.variables.items():
                options.append('%s=%s' % (variable, value))
            kw['options'] = ' '.join(options)
        if self.calibrate:
            self.calibration(*args, **kw)
        else:
            self.uptime()
            self.startup(*args, **kw)
            self.full(*args, **kw)
            self.null(*args, **kw)

    def trace(self, graph, name, value, units, sort=None):
        fmt = "TRACE: graph=%s name=%s value=%s units=%s"
        line = fmt % (graph, name, value, units)
        if sort is not None:
          line = line + (' sort=%s' % sort)
        line = line + '\n'
        sys.stdout.write(line)
        sys.stdout.flush()

    def report_traces(self, trace, stats):
        self.trace('TimeSCons-elapsed',
                   trace,
                   self.elapsed_time(),
                   "seconds",
                   sort=0)
        for name, args in stats.items():
            self.trace(name, trace, **args)

    def uptime(self):
        try:
            fp = open('/proc/loadavg')
        except EnvironmentError:
            pass
        else:
            avg1, avg5, avg15 = fp.readline().split(" ")[:3]
            fp.close()
            self.trace('load-average',  'average1', avg1, 'processes')
            self.trace('load-average',  'average5', avg5, 'processes')
            self.trace('load-average',  'average15', avg15, 'processes')

    def collect_stats(self, input):
        result = {}
        for stat in StatList:
            m = stat.expression.search(input)
            if m:
                value = stat.convert(m.group(1))
                # The dict keys match the keyword= arguments
                # of the trace() method above so they can be
                # applied directly to that call.
                result[stat.name] = {'value':value, 'units':stat.units}
        return result

    def add_timing_options(self, kw, additional=None):
        """
        Add the necessary timings options to the kw['options'] value.
        """
        options = kw.get('options', '')
        if additional is not None:
            options += additional
        kw['options'] = options + ' --debug=memory,time'

    def startup(self, *args, **kw):
        """
        Runs scons with the --help option.

        This serves as a way to isolate just the amount of startup time
        spent reading up the configuration, since --help exits before any
        "real work" is done.
        """
        self.add_timing_options(kw, ' --help')
        # Ignore the exit status.  If the --help run dies, we just
        # won't report any statistics for it, but we can still execute
        # the full and null builds.
        kw['status'] = None
        self.run(*args, **kw)
        sys.stdout.write(self.stdout())
        stats = self.collect_stats(self.stdout())
        # Delete the time-commands, since no commands are ever
        # executed on the help run and it is (or should be) always 0.0.
        del stats['time-commands']
        self.report_traces('startup', stats)

    def full(self, *args, **kw):
        """
        Runs a full build of SCons.
        """
        self.add_timing_options(kw)
        self.run(*args, **kw)
        sys.stdout.write(self.stdout())
        stats = self.collect_stats(self.stdout())
        self.report_traces('full', stats)
        self.trace('full-memory', 'initial', **stats['memory-initial'])
        self.trace('full-memory', 'prebuild', **stats['memory-prebuild'])
        self.trace('full-memory', 'final', **stats['memory-final'])

    def calibration(self, *args, **kw):
        """
        Runs a full build of SCons, but only reports calibration
        information (the variable(s) that were set for this configuration,
        and the elapsed time to run.
        """
        self.add_timing_options(kw)
        self.run(*args, **kw)
        for variable in self.calibrate_variables:
            value = self.variables[variable]
            sys.stdout.write('VARIABLE: %s=%s\n' % (variable, value))
        sys.stdout.write('ELAPSED: %s\n' % self.elapsed_time())

    def null(self, *args, **kw):
        """
        Runs an up-to-date null build of SCons.
        """
        # TODO(sgk):  allow the caller to specify the target (argument)
        # that must be up-to-date.
        self.add_timing_options(kw)
        self.up_to_date(arguments='.', **kw)
        sys.stdout.write(self.stdout())
        stats = self.collect_stats(self.stdout())
        # time-commands should always be 0.0 on a null build, because
        # no commands should be executed.  Remove it from the stats
        # so we don't trace it, but only if it *is* 0 so that we'll
        # get some indication if a supposedly-null build actually does
        # build something.
        if float(stats['time-commands']['value']) == 0.0:
            del stats['time-commands']
        self.report_traces('null', stats)
        self.trace('null-memory', 'initial', **stats['memory-initial'])
        self.trace('null-memory', 'prebuild', **stats['memory-prebuild'])
        self.trace('null-memory', 'final', **stats['memory-final'])

    def elapsed_time(self):
        """
        Returns the elapsed time of the most recent command execution.
        """
        return self.endTime - self.startTime

    def run(self, *args, **kw):
        """
        Runs a single build command, capturing output in the specified file.

        Because this class is about timing SCons, we record the start
        and end times of the elapsed execution, and also add the
        --debug=memory and --debug=time options to have SCons report
        its own memory and timing statistics.
        """
        self.startTime = time.time()
        try:
            result = TestSCons.run(self, *args, **kw)
        finally:
            self.endTime = time.time()
        return result

    def copy_timing_configuration(self, source_dir, dest_dir):
        """
        Copies the timing configuration from the specified source_dir (the
        directory in which the controlling script lives) to the specified
        dest_dir (a temporary working directory).

        This ignores all files and directories that begin with the string
        'TimeSCons-', and all '.svn' subdirectories.
        """
        for root, dirs, files in os.walk(source_dir):
            if '.svn' in dirs:
                dirs.remove('.svn')
            dirs = [ d for d in dirs if not d.startswith('TimeSCons-') ]
            files = [ f for f in files if not f.startswith('TimeSCons-') ]
            for dirname in dirs:
                source = os.path.join(root, dirname)
                destination = source.replace(source_dir, dest_dir)
                os.mkdir(destination)
                if sys.platform != 'win32':
                    shutil.copystat(source, destination)
            for filename in files:
                source = os.path.join(root, filename)
                destination = source.replace(source_dir, dest_dir)
                shutil.copy2(source, destination)


# In some environments, $AR will generate a warning message to stderr
# if the library doesn't previously exist and is being created.  One
# way to fix this is to tell AR to be quiet (sometimes the 'c' flag),
# but this is difficult to do in a platform-/implementation-specific
# method.  Instead, we will use the following as a stderr match for
# tests that use AR so that we will view zero or more "ar: creating
# <file>" messages to be successful executions of the test (see
# test/AR.py for sample usage).

noisy_ar=r'(ar: creating( archive)? \S+\n?)*'

# Local Variables:
# tab-width:4
# indent-tabs-mode:nil
# End:
# vim: set expandtab tabstop=4 shiftwidth=4: