__init__.py

"""SCons.Tool.qt5

Tool-specific initialization for Qt5.

There normally shouldn't be any need to import this module directly.
It will usually be imported through the generic SCons.Tool.Tool()
selection method.

"""

#
# Copyright (c) 2001-7,2010,2011,2012 The SCons Foundation
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#

import os.path
import re
import subprocess

import SCons.Action
import SCons.Builder
import SCons.Defaults
import SCons.Scanner
import SCons.Tool
import SCons.Util

class ToolQt5Warning(SCons.Warnings.Warning):
    pass

class GeneratedMocFileNotIncluded(ToolQt5Warning):
    pass

class QtdirNotFound(ToolQt5Warning):
    pass

SCons.Warnings.enableWarningClass(ToolQt5Warning)

try:
    sorted
except NameError:
    # Pre-2.4 Python has no sorted() function.
    #
    # The pre-2.4 Python list.sort() method does not support
    # list.sort(key=) nor list.sort(reverse=) keyword arguments, so
    # we must implement the functionality of those keyword arguments
    # by hand instead of passing them to list.sort().
    def sorted(iterable, cmp=None, key=None, reverse=0):
        if key is not None:
            result = [(key(x), x) for x in iterable]
        else:
            result = iterable[:]
        if cmp is None:
            # Pre-2.3 Python does not support list.sort(None).
            result.sort()
        else:
            result.sort(cmp)
        if key is not None:
            result = [t1 for t0,t1 in result]
        if reverse:
            result.reverse()
        return result

def _contents_regex(e):
    # get_contents() of scons nodes returns a binary buffer, so we convert the regexes also to binary here
    # this won't work for specific encodings like UTF-16, but most of the time we will be fine here.
    # note that the regexes used here are always pure ascii, so we don't have an issue here.
    e = e.encode('ascii')
    return e

qrcinclude_re = re.compile(r'<file[^>]*>([^<]*)</file>', re.M)

mocver_re = re.compile(_contents_regex(r'.*(\d+)\.(\d+)\.(\d+).*'))

def transformToWinePath(path) :
    pipe = subprocess.Popen('winepath -w "%s"'%path, shell=True, stdout=PIPE).stdout
    return pipe.read().strip().replace('\\','/')

header_extensions = [".h", ".hxx", ".hpp", ".hh"]
if SCons.Util.case_sensitive_suffixes('.h', '.H'):
    header_extensions.append('.H')
# TODO: The following two lines will work when integrated back to SCons
# TODO: Meanwhile the third line will do the work
#cplusplus = __import__('c++', globals(), locals(), [])
#cxx_suffixes = cplusplus.CXXSuffixes
cxx_suffixes = [".c", ".cxx", ".cpp", ".cc"]

def checkMocIncluded(target, source, env):
    moc = target[0]
    cpp = source[0]
    # looks like cpp.includes is cleared before the build stage :-(
    # not really sure about the path transformations (moc.cwd? cpp.cwd?) :-/
    path = SCons.Defaults.CScan.path_function(env, moc.cwd)
    includes = SCons.Defaults.CScan(cpp, env, path)
    if not moc in includes:
        SCons.Warnings.warn(
            GeneratedMocFileNotIncluded,
            "Generated moc file '%s' is not included by '%s'" %
            (str(moc), str(cpp)))

def find_file(filename, paths, node_factory):
    for dir in paths:
        node = node_factory(filename, dir)
        if node.rexists():
            return node
    return None

class _Automoc:
    """
    Callable class, which works as an emitter for Programs, SharedLibraries and
    StaticLibraries.
    """

    def __init__(self, objBuilderName):
        self.objBuilderName = objBuilderName
        # some regular expressions:
        # Q_OBJECT detection
        self.qo_search = re.compile(_contents_regex(r'[^A-Za-z0-9]Q_OBJECT[^A-Za-z0-9]'))
        # cxx and c comment 'eater'
        self.ccomment = re.compile(_contents_regex(r'/\*(.*?)\*/'),re.S)
        self.cxxcomment = re.compile(_contents_regex(r'//.*$'),re.M)
        # we also allow Q_OBJECT in a literal string
        self.literal_qobject = re.compile(_contents_regex(r'"[^\n]*Q_OBJECT[^\n]*"'))
        
    def create_automoc_options(self, env):
        """
        Create a dictionary with variables related to Automocing,
        based on the current environment.
        Is executed once in the __call__ routine.  
        """
        moc_options = {'auto_scan' : True,
                       'auto_scan_strategy' : 0,
                       'gobble_comments' : 0,
                       'debug' : 0,
                       'auto_cpppath' : True,
                       'cpppaths' : []}
        try:
            if int(env.subst('$QT5_AUTOSCAN')) == 0:
                moc_options['auto_scan'] = False
        except ValueError:
            pass
        try:
            moc_options['auto_scan_strategy'] = int(env.subst('$QT5_AUTOSCAN_STRATEGY'))
        except ValueError:
            pass
        try:
            moc_options['gobble_comments'] = int(env.subst('$QT5_GOBBLECOMMENTS'))
        except ValueError:
            pass
        try:
            moc_options['debug'] = int(env.subst('$QT5_DEBUG'))
        except ValueError:
            pass
        try:
            if int(env.subst('$QT5_AUTOMOC_SCANCPPPATH')) == 0:
                moc_options['auto_cpppath'] = False
        except ValueError:
            pass
        if moc_options['auto_cpppath']:
            paths = env.get('QT5_AUTOMOC_CPPPATH', [])
            if not paths:
                paths = env.get('CPPPATH', [])
            moc_options['cpppaths'].extend(paths)
        
        return moc_options

    def __automoc_strategy_simple(self, env, moc_options, 
                                  cpp, cpp_contents, out_sources):
        """
        Default Automoc strategy (Q_OBJECT driven): detect a header file
        (alongside the current cpp/cxx) that contains a Q_OBJECT
        macro...and MOC it.
        If a Q_OBJECT macro is also found in the cpp/cxx itself,
        it gets MOCed too.
        """
        
        h=None
        for h_ext in header_extensions:
            # try to find the header file in the corresponding source
            # directory
            hname = self.splitext(cpp.name)[0] + h_ext
            h = find_file(hname, [cpp.get_dir()]+moc_options['cpppaths'], env.File)
            if h:
                if moc_options['debug']:
                    print("scons: qt5: Scanning '%s' (header of '%s')" % (str(h), str(cpp)))
                h_contents = h.get_contents()
                if moc_options['gobble_comments']:
                    h_contents = self.ccomment.sub(_contents_regex(''), h_contents)
                    h_contents = self.cxxcomment.sub(_contents_regex(''), h_contents)
                h_contents = self.literal_qobject.sub(_contents_regex('""'), h_contents)
                break
        if not h and moc_options['debug']:
            print("scons: qt5: no header for '%s'." % (str(cpp)))
        if h and self.qo_search.search(h_contents):
            # h file with the Q_OBJECT macro found -> add moc_cpp
            moc_cpp = env.Moc5(h)
            if moc_options['debug']:
                print("scons: qt5: found Q_OBJECT macro in '%s', moc'ing to '%s'" % (str(h), str(moc_cpp)))
            
            # Now, check whether the corresponding CPP file
            # includes the moc'ed output directly...
            inc_moc_cpp = _contents_regex(r'^\s*#\s*include\s+"%s"' % str(moc_cpp[0]))
            if cpp and re.search(inc_moc_cpp, cpp_contents, re.M):
                if moc_options['debug']:
                    print("scons: qt5: CXX file '%s' directly includes the moc'ed output '%s', no compiling required" % (str(cpp), str(moc_cpp)))
                env.Depends(cpp, moc_cpp)
            else:
                moc_o = self.objBuilder(moc_cpp)
                if moc_options['debug']:
                    print("scons: qt5: compiling '%s' to '%s'" % (str(cpp), str(moc_o)))
                out_sources.extend(moc_o)
        if cpp and self.qo_search.search(cpp_contents):
            # cpp file with Q_OBJECT macro found -> add moc
            # (to be included in cpp)
            moc = env.Moc5(cpp)
            env.Ignore(moc, moc)
            if moc_options['debug']:
                print("scons: qt5: found Q_OBJECT macro in '%s', moc'ing to '%s'" % (str(cpp), str(moc)))

    def __automoc_strategy_include_driven(self, env, moc_options,
                                          cpp, cpp_contents, out_sources):
        """
        Automoc strategy #1 (include driven): searches for "include"
        statements of MOCed files in the current cpp/cxx file.
        This strategy tries to add support for the compilation
        of the qtsolutions...
        """
        if self.splitext(str(cpp))[1] in cxx_suffixes:
            added = False
            h_moc = "%s%s%s" % (env.subst('$QT5_XMOCHPREFIX'),
                                self.splitext(cpp.name)[0],
                                env.subst('$QT5_XMOCHSUFFIX'))
            cxx_moc = "%s%s%s" % (env.subst('$QT5_XMOCCXXPREFIX'),
                                  self.splitext(cpp.name)[0],
                                  env.subst('$QT5_XMOCCXXSUFFIX'))
            inc_h_moc = _contents_regex(r'#include\s+"%s"' % h_moc)
            inc_cxx_moc = _contents_regex(r'#include\s+"%s"' % cxx_moc)
            
            # Search for special includes in qtsolutions style
            if cpp and re.search(inc_h_moc, cpp_contents):
                # cpp file with #include directive for a MOCed header found -> add moc
                
                # Try to find header file                    
                h=None
                hname=""
                for h_ext in header_extensions:
                    # Try to find the header file in the
                    # corresponding source directory
                    hname = self.splitext(cpp.name)[0] + h_ext
                    h = find_file(hname, [cpp.get_dir()]+moc_options['cpppaths'], env.File)
                    if h:
                        if moc_options['debug']:
                            print("scons: qt5: Scanning '%s' (header of '%s')" % (str(h), str(cpp)))
                        h_contents = h.get_contents()
                        if moc_options['gobble_comments']:
                            h_contents = self.ccomment.sub('', h_contents)
                            h_contents = self.cxxcomment.sub('', h_contents)
                        h_contents = self.literal_qobject.sub('""', h_contents)
                        break
                if not h and moc_options['debug']:
                    print("scons: qt5: no header for '%s'." % (str(cpp)))
                if h and self.qo_search.search(h_contents):
                    # h file with the Q_OBJECT macro found -> add moc_cpp
                    moc_cpp = env.XMoc5(h)
                    env.Ignore(moc_cpp, moc_cpp)
                    added = True
                    # Removing file from list of sources, because it is not to be
                    # compiled but simply included by the cpp/cxx file.
                    for idx, s in enumerate(out_sources):
                        if hasattr(s, "sources") and len(s.sources) > 0:
                            if str(s.sources[0]) == h_moc:
                                out_sources.pop(idx)
                                break
                    if moc_options['debug']:
                        print("scons: qt5: found Q_OBJECT macro in '%s', moc'ing to '%s'" % (str(h), str(h_moc)))
                else:
                    if moc_options['debug']:
                        print("scons: qt5: found no Q_OBJECT macro in '%s', but a moc'ed version '%s' gets included in '%s'" % (str(h), inc_h_moc, cpp.name))

            if cpp and re.search(inc_cxx_moc, cpp_contents):
                # cpp file with #include directive for a MOCed cxx file found -> add moc
                if self.qo_search.search(cpp_contents):
                    moc = env.XMoc5(target=cxx_moc, source=cpp)
                    env.Ignore(moc, moc)
                    added = True
                    if moc_options['debug']:
                        print("scons: qt5: found Q_OBJECT macro in '%s', moc'ing to '%s'" % (str(cpp), str(moc)))
                else:
                    if moc_options['debug']:
                        print("scons: qt5: found no Q_OBJECT macro in '%s', although a moc'ed version '%s' of itself gets included" % (cpp.name, inc_cxx_moc))

            if not added:
                # Fallback to default Automoc strategy (Q_OBJECT driven)
               self.__automoc_strategy_simple(env, moc_options, cpp,
                                              cpp_contents, out_sources)
        
    def __call__(self, target, source, env):
        """
        Smart autoscan function. Gets the list of objects for the Program
        or Lib. Adds objects and builders for the special qt5 files.
        """
        moc_options = self.create_automoc_options(env)
        
        # some shortcuts used in the scanner
        self.splitext = SCons.Util.splitext
        self.objBuilder = getattr(env, self.objBuilderName)

        # The following is kind of hacky to get builders working properly (FIXME)
        objBuilderEnv = self.objBuilder.env
        self.objBuilder.env = env
        mocBuilderEnv = env.Moc5.env
        env.Moc5.env = env
        xMocBuilderEnv = env.XMoc5.env
        env.XMoc5.env = env
        
        # make a deep copy for the result; MocH objects will be appended
        out_sources = source[:]

        for obj in source:
            if not moc_options['auto_scan']:
                break
            if isinstance(obj,str):  # big kludge!
                print("scons: qt5: '%s' MAYBE USING AN OLD SCONS VERSION AND NOT CONVERTED TO 'File'. Discarded." % str(obj))
                continue
            if not obj.has_builder():
                # binary obj file provided
                if moc_options['debug']:
                    print("scons: qt5: '%s' seems to be a binary. Discarded." % str(obj))
                continue
            cpp = obj.sources[0]
            if not self.splitext(str(cpp))[1] in cxx_suffixes:
                if moc_options['debug']:
                    print("scons: qt5: '%s' is no cxx file. Discarded." % str(cpp)) 
                # c or fortran source
                continue
            try:
                cpp_contents = cpp.get_contents()
                if moc_options['gobble_comments']:
                    cpp_contents = self.ccomment.sub('', cpp_contents)
                    cpp_contents = self.cxxcomment.sub('', cpp_contents)
                cpp_contents = self.literal_qobject.sub('""', cpp_contents)
            except: continue # may be an still not generated source
            
            if moc_options['auto_scan_strategy'] == 0:
                # Default Automoc strategy (Q_OBJECT driven)
                self.__automoc_strategy_simple(env, moc_options,
                                               cpp, cpp_contents, out_sources)
            else:
                # Automoc strategy #1 (include driven)
                self.__automoc_strategy_include_driven(env, moc_options,
                                                       cpp, cpp_contents, out_sources)

        # restore the original env attributes (FIXME)
        self.objBuilder.env = objBuilderEnv
        env.Moc5.env = mocBuilderEnv
        env.XMoc5.env = xMocBuilderEnv

        # We return the set of source entries as sorted sequence, else
        # the order might accidentally change from one build to another
        # and trigger unwanted rebuilds. For proper sorting, a key function
        # has to be specified...FS.Entry (and Base nodes in general) do not
        # provide a __cmp__, for performance reasons. 
        return (target, sorted(set(out_sources), key=lambda entry : str(entry)))

AutomocShared = _Automoc('SharedObject')
AutomocStatic = _Automoc('StaticObject')

def _detect(env):
    """Not really safe, but fast method to detect the Qt5 library"""
    try: return env['QT5DIR']
    except KeyError: pass

    try: return env['QTDIR']
    except KeyError: pass

    try: return os.environ['QT5DIR']
    except KeyError: pass

    try: return os.environ['QTDIR']
    except KeyError: pass

    moc = env.WhereIs('moc-qt5') or env.WhereIs('moc5') or env.WhereIs('moc')
    if moc:
        pipes = subprocess.Popen('%s -v' % moc,
                                 shell=True, stdin=subprocess.PIPE,
                                 stdout=subprocess.PIPE,
                                 stderr=subprocess.PIPE,
                                 close_fds=True)
        vernumber = pipes.stdout.read()
        vernumber = mocver_re.match(vernumber)
        if vernumber:
            vernumber = [ int(x) for x in vernumber.groups() ]
            if vernumber < [5, 0, 0]:
                vernumber = '.'.join([str(x) for x in vernumber])
                moc = None
                SCons.Warnings.warn(
                    QtdirNotFound,
                    "QT5DIR variable not defined, and detected moc is for Qt %s" % vernumber)

        QT5DIR = os.path.dirname(os.path.dirname(moc))
        SCons.Warnings.warn(
            QtdirNotFound,
            "QT5DIR variable is not defined, using moc executable as a hint (QT5DIR=%s)" % QT5DIR)
        return QT5DIR

    raise SCons.Errors.StopError(
        QtdirNotFound,
        "Could not detect Qt 5 installation")
    return None


def __scanResources(node, env, path, arg):
    # Helper function for scanning .qrc resource files
    # I've been careful on providing names relative to the qrc file
    # If that was not needed this code could be simplified a lot
    def recursiveFiles(basepath, path) :
        result = []
        for item in os.listdir(os.path.join(basepath, path)) :
            itemPath = os.path.join(path, item)
            if os.path.isdir(os.path.join(basepath, itemPath)) :
                result += recursiveFiles(basepath, itemPath)
            else:
                result.append(itemPath)
        return result
    # we assume the default xml encoding (utf-8) here
    contents = node.get_contents().decode('utf-8')
    includes = qrcinclude_re.findall(contents)
    qrcpath = os.path.dirname(node.path)
    dirs = [included for included in includes if os.path.isdir(os.path.join(qrcpath,included))]
    # dirs need to include files recursively
    for dir in dirs :
        includes.remove(dir)
        includes+=recursiveFiles(qrcpath,dir)
    return includes

#
# Scanners
#
__qrcscanner = SCons.Scanner.Scanner(name = 'qrcfile',
    function = __scanResources,
    argument = None,
    skeys = ['.qrc'])

#
# Emitters
#
def __qrc_path(head, prefix, tail, suffix):
    if head:
        if tail:
            return os.path.join(head, "%s%s%s" % (prefix, tail, suffix))
        else:
            return "%s%s%s" % (prefix, head, suffix)
    else:
        return "%s%s%s" % (prefix, tail, suffix)
def __qrc_emitter(target, source, env):
    sourceBase, sourceExt = os.path.splitext(SCons.Util.to_String(source[0]))
    sHead = None
    sTail = sourceBase
    if sourceBase:
        sHead, sTail = os.path.split(sourceBase)

    t = __qrc_path(sHead, env.subst('$QT5_QRCCXXPREFIX'),
                   sTail, env.subst('$QT5_QRCCXXSUFFIX'))

    return t, source

#
# Action generators
#
def __moc_generator_from_h(source, target, env, for_signature):
    pass_defines = False
    try:
        if int(env.subst('$QT5_CPPDEFINES_PASSTOMOC')) == 1:
            pass_defines = True
    except ValueError:
        pass
    
    if pass_defines:
        return '$QT5_MOC $QT5_MOCDEFINES $QT5_MOCFROMHFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE'
    else:
        return '$QT5_MOC $QT5_MOCFROMHFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE'

def __moc_generator_from_cxx(source, target, env, for_signature):
    pass_defines = False
    try:
        if int(env.subst('$QT5_CPPDEFINES_PASSTOMOC')) == 1:
            pass_defines = True
    except ValueError:
        pass
    
    if pass_defines:
        return ['$QT5_MOC $QT5_MOCDEFINES $QT5_MOCFROMCXXFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE',
                SCons.Action.Action(checkMocIncluded,None)]
    else:
        return ['$QT5_MOC $QT5_MOCFROMCXXFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE',
                SCons.Action.Action(checkMocIncluded,None)]

def __mocx_generator_from_h(source, target, env, for_signature):
    pass_defines = False
    try:
        if int(env.subst('$QT5_CPPDEFINES_PASSTOMOC')) == 1:
            pass_defines = True
    except ValueError:
        pass
    
    if pass_defines:
        return '$QT5_MOC $QT5_MOCDEFINES $QT5_MOCFROMHFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE'
    else:
        return '$QT5_MOC $QT5_MOCFROMHFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE'

def __mocx_generator_from_cxx(source, target, env, for_signature):
    pass_defines = False
    try:
        if int(env.subst('$QT5_CPPDEFINES_PASSTOMOC')) == 1:
            pass_defines = True
    except ValueError:
        pass
    
    if pass_defines:
        return ['$QT5_MOC $QT5_MOCDEFINES $QT5_MOCFROMCXXFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE',
                SCons.Action.Action(checkMocIncluded,None)]
    else:
        return ['$QT5_MOC $QT5_MOCFROMCXXFLAGS $QT5_MOCINCFLAGS -o $TARGET $SOURCE',
                SCons.Action.Action(checkMocIncluded,None)]

def __qrc_generator(source, target, env, for_signature):
    name_defined = False
    try:
        if env.subst('$QT5_QRCFLAGS').find('-name') >= 0:
            name_defined = True
    except ValueError:
        pass
    
    if name_defined:
        return '$QT5_RCC $QT5_QRCFLAGS $SOURCE -o $TARGET'
    else:
        qrc_suffix = env.subst('$QT5_QRCSUFFIX')
        src = str(source[0])
        head, tail = os.path.split(src)
        if tail:
            src = tail
        qrc_suffix = env.subst('$QT5_QRCSUFFIX')
        if src.endswith(qrc_suffix):
            qrc_stem = src[:-len(qrc_suffix)]
        else:
            qrc_stem = src
        return '$QT5_RCC $QT5_QRCFLAGS -name %s $SOURCE -o $TARGET' % qrc_stem

#
# Builders
#
__ts_builder = SCons.Builder.Builder(        
        action = SCons.Action.Action('$QT5_LUPDATECOM','$QT5_LUPDATECOMSTR'),
        suffix = '.ts',
        source_factory = SCons.Node.FS.Entry)
__qm_builder = SCons.Builder.Builder(
        action = SCons.Action.Action('$QT5_LRELEASECOM','$QT5_LRELEASECOMSTR'),
        src_suffix = '.ts',
        suffix = '.qm')
__qrc_builder = SCons.Builder.Builder(
        action = SCons.Action.CommandGeneratorAction(__qrc_generator,
                                                    {'cmdstr':'$QT5_QRCCOMSTR'}),
        source_scanner = __qrcscanner,
        src_suffix = '$QT5_QRCSUFFIX',
        suffix = '$QT5_QRCCXXSUFFIX',
        prefix = '$QT5_QRCCXXPREFIX',
        single_source = 1)
__ex_moc_builder = SCons.Builder.Builder(
        action = SCons.Action.CommandGeneratorAction(__moc_generator_from_h,
                                                  {'cmdstr':'$QT5_MOCFROMHCOMSTR'}))
__ex_uic_builder = SCons.Builder.Builder(
        action = SCons.Action.Action('$QT5_UICCOM', '$QT5_UICCOMSTR'),
        src_suffix = '.ui')


#
# Wrappers (pseudo-Builders)
#
def Ts5(env, target, source=None, *args, **kw):
    """
    A pseudo-Builder wrapper around the LUPDATE executable of Qt5.
        lupdate [options] [source-file|path]... -ts ts-files
    """
    if not SCons.Util.is_List(target):
        target = [target]
    if not source:
        source = target[:]
    if not SCons.Util.is_List(source):
        source = [source]

    # Check QT5_CLEAN_TS and use NoClean() function
    clean_ts = False
    try:
        if int(env.subst('$QT5_CLEAN_TS')) == 1:
            clean_ts = True
    except ValueError:
        pass
    
    result = []
    for t in target:
        obj = __ts_builder.__call__(env, t, source, **kw)
        # Prevent deletion of the .ts file, unless explicitly specified
        if not clean_ts:
            env.NoClean(obj)
        # Always make our target "precious", such that it is not deleted
        # prior to a rebuild
        env.Precious(obj)
        # Add to resulting target list        
        result.extend(obj)

    return result

def Qm5(env, target, source=None, *args, **kw):
    """
    A pseudo-Builder wrapper around the LRELEASE executable of Qt5.
        lrelease [options] ts-files [-qm qm-file]
    """
    if not SCons.Util.is_List(target):
        target = [target]
    if not source:
        source = target[:]
    if not SCons.Util.is_List(source):
        source = [source]

    result = []    
    for t in target:
        result.extend(__qm_builder.__call__(env, t, source, **kw))

    return result

def Qrc5(env, target, source=None, *args, **kw):
    """
    A pseudo-Builder wrapper around the RCC executable of Qt5.
        rcc [options] qrc-files -o out-file
    """
    if not SCons.Util.is_List(target):
        target = [target]
    if not source:
        source = target[:]
    if not SCons.Util.is_List(source):
        source = [source]

    result = []
    for t, s in zip(target, source):
        result.extend(__qrc_builder.__call__(env, t, s, **kw))

    return result

def ExplicitMoc5(env, target, source, *args, **kw):
    """
    A pseudo-Builder wrapper around the MOC executable of Qt5.
        moc [options] <header-file>
    """
    if not SCons.Util.is_List(target):
        target = [target]
    if not SCons.Util.is_List(source):
        source = [source]

    result = []
    for t in target:
        # Is it a header or a cxx file?
        result.extend(__ex_moc_builder.__call__(env, t, source, **kw))

    return result

def ExplicitUic5(env, target, source, *args, **kw):
    """
    A pseudo-Builder wrapper around the UIC executable of Qt5.
        uic [options] <uifile>
    """
    if not SCons.Util.is_List(target):
        target = [target]
    if not SCons.Util.is_List(source):
        source = [source]

    result = []
    for t in target:
        result.extend(__ex_uic_builder.__call__(env, t, source, **kw))

    return result

def generate(env):
    """Add Builders and construction variables for qt5 to an Environment."""

    suffixes = [
        '-qt5',
        '-qt5.exe',
        '5',
        '5.exe',
        '',
        '.exe',
    ]
    command_suffixes = ['-qt5', '5', '']
        
    def locateQt5Command(env, command, qtdir) :
        triedPaths = []
        for suffix in suffixes :
            fullpath = os.path.join(qtdir,'bin',command + suffix)
            if os.access(fullpath, os.X_OK) :
                return fullpath
            triedPaths.append(fullpath)

        fullpath = env.Detect([command+s for s in command_suffixes])
        if not (fullpath is None) : return fullpath

        raise Exception("Qt5 command '" + command + "' not found. Tried: " + ', '.join(triedPaths))

    CLVar = SCons.Util.CLVar
    Action = SCons.Action.Action
    Builder = SCons.Builder.Builder

    env['QT5DIR']  = _detect(env)
    # TODO: 'Replace' should be 'SetDefault'
#    env.SetDefault(
    env.Replace(
        QT5DIR  = _detect(env),
        QT5_BINPATH = os.path.join('$QT5DIR', 'bin'),
        # TODO: This is not reliable to QT5DIR value changes but needed in order to support '-qt5' variants
        QT5_MOC = locateQt5Command(env,'moc', env['QT5DIR']),
        QT5_UIC = locateQt5Command(env,'uic', env['QT5DIR']),
        QT5_RCC = locateQt5Command(env,'rcc', env['QT5DIR']),
        QT5_LUPDATE = locateQt5Command(env,'lupdate', env['QT5DIR']),
        QT5_LRELEASE = locateQt5Command(env,'lrelease', env['QT5DIR']),

        QT5_AUTOSCAN = 1, # Should the qt5 tool try to figure out, which sources are to be moc'ed?
        QT5_AUTOSCAN_STRATEGY = 0, # While scanning for files to moc, should we search for includes in qtsolutions style?
        QT5_GOBBLECOMMENTS = 0, # If set to 1, comments are removed before scanning cxx/h files.
        QT5_CPPDEFINES_PASSTOMOC = 1, # If set to 1, all CPPDEFINES get passed to the moc executable.
        QT5_CLEAN_TS = 0, # If set to 1, translation files (.ts) get cleaned on 'scons -c'
        QT5_AUTOMOC_SCANCPPPATH = 1, # If set to 1, the CPPPATHs (or QT5_AUTOMOC_CPPPATH) get scanned for moc'able files
        QT5_AUTOMOC_CPPPATH = [], # Alternative paths that get scanned for moc files

        # Some Qt5 specific flags. I don't expect someone wants to
        # manipulate those ...
        QT5_UICFLAGS = CLVar(''),
        QT5_MOCFROMHFLAGS = CLVar(''),
        QT5_MOCFROMCXXFLAGS = CLVar('-i'),
        QT5_QRCFLAGS = '',
        QT5_LUPDATEFLAGS = '',
        QT5_LRELEASEFLAGS = '',

        # suffixes/prefixes for the headers / sources to generate
        QT5_UISUFFIX = '.ui',
        QT5_UICDECLPREFIX = 'ui_',
        QT5_UICDECLSUFFIX = '.h',
        QT5_MOCINCPREFIX = '-I',
        QT5_MOCHPREFIX = 'moc_',
        QT5_MOCHSUFFIX = '$CXXFILESUFFIX',
        QT5_MOCCXXPREFIX = '',
        QT5_MOCCXXSUFFIX = '.moc',
        QT5_QRCSUFFIX = '.qrc',
        QT5_QRCCXXSUFFIX = '$CXXFILESUFFIX',
        QT5_QRCCXXPREFIX = 'qrc_',
        QT5_MOCDEFPREFIX = '-D',
        QT5_MOCDEFSUFFIX = '',
        QT5_MOCDEFINES = '${_defines(QT5_MOCDEFPREFIX, CPPDEFINES, QT5_MOCDEFSUFFIX, __env__)}',
        QT5_MOCCPPPATH = [],
        QT5_MOCINCFLAGS = '$( ${_concat(QT5_MOCINCPREFIX, QT5_MOCCPPPATH, INCSUFFIX, __env__, RDirs)} $)',

        # Commands for the qt5 support ...
        QT5_UICCOM = '$QT5_UIC $QT5_UICFLAGS -o $TARGET $SOURCE',
        QT5_LUPDATECOM = '$QT5_LUPDATE $QT5_LUPDATEFLAGS $SOURCES -ts $TARGET',
        QT5_LRELEASECOM = '$QT5_LRELEASE $QT5_LRELEASEFLAGS -qm $TARGET $SOURCES',
        
        # Specialized variables for the Extended Automoc support
        # (Strategy #1 for qtsolutions)
        QT5_XMOCHPREFIX = 'moc_',
        QT5_XMOCHSUFFIX = '.cpp',
        QT5_XMOCCXXPREFIX = '',
        QT5_XMOCCXXSUFFIX = '.moc',
                
        )

    env.AddMethod(Ts5, "Ts5")
    env.AddMethod(Qm5, "Qm5")
    env.AddMethod(Qrc5, "Qrc5")
    env.AddMethod(ExplicitMoc5, "ExplicitMoc5")
    env.AddMethod(ExplicitUic5, "ExplicitUic5")

    # Interface builder
    uic5builder = Builder(
        action = SCons.Action.Action('$QT5_UICCOM', '$QT5_UICCOMSTR'),
        src_suffix='$QT5_UISUFFIX',
        suffix='$QT5_UICDECLSUFFIX',
        prefix='$QT5_UICDECLPREFIX',
        single_source = True
        #TODO: Consider the uiscanner on new scons version
        )
    env['BUILDERS']['Uic5'] = uic5builder

    # Metaobject builder
    mocBld = Builder(action={}, prefix={}, suffix={})
    for h in header_extensions:
        act = SCons.Action.CommandGeneratorAction(__moc_generator_from_h,
                                                  {'cmdstr':'$QT5_MOCFROMHCOMSTR'})
        mocBld.add_action(h, act)
        mocBld.prefix[h] = '$QT5_MOCHPREFIX'
        mocBld.suffix[h] = '$QT5_MOCHSUFFIX'
    for cxx in cxx_suffixes:
        act = SCons.Action.CommandGeneratorAction(__moc_generator_from_cxx,
                                                  {'cmdstr':'$QT5_MOCFROMCXXCOMSTR'})
        mocBld.add_action(cxx, act)
        mocBld.prefix[cxx] = '$QT5_MOCCXXPREFIX'
        mocBld.suffix[cxx] = '$QT5_MOCCXXSUFFIX'
    env['BUILDERS']['Moc5'] = mocBld

    # Metaobject builder for the extended auto scan feature 
    # (Strategy #1 for qtsolutions)
    xMocBld = Builder(action={}, prefix={}, suffix={})
    for h in header_extensions:
        act = SCons.Action.CommandGeneratorAction(__mocx_generator_from_h,
                                                  {'cmdstr':'$QT5_MOCXFROMHCOMSTR'})
        xMocBld.add_action(h, act)
        xMocBld.prefix[h] = '$QT5_XMOCHPREFIX'
        xMocBld.suffix[h] = '$QT5_XMOCHSUFFIX'
    for cxx in cxx_suffixes:
        act = SCons.Action.CommandGeneratorAction(__mocx_generator_from_cxx,
                                                  {'cmdstr':'$QT5_MOCXFROMCXXCOMSTR'})
        xMocBld.add_action(cxx, act)
        xMocBld.prefix[cxx] = '$QT5_XMOCCXXPREFIX'
        xMocBld.suffix[cxx] = '$QT5_XMOCCXXSUFFIX'
    env['BUILDERS']['XMoc5'] = xMocBld

    # Add the Qrc5 action to the CXX file builder (registers the
    # *.qrc extension with the Environment)     
    cfile_builder, cxxfile_builder = SCons.Tool.createCFileBuilders(env)
    qrc_act = SCons.Action.CommandGeneratorAction(__qrc_generator,
                                                  {'cmdstr':'$QT5_QRCCOMSTR'})
    cxxfile_builder.add_action('$QT5_QRCSUFFIX', qrc_act)    
    cxxfile_builder.add_emitter('$QT5_QRCSUFFIX', __qrc_emitter)    
    env.Append(SCANNERS=__qrcscanner)

    # We use the emitters of Program / StaticLibrary / SharedLibrary
    # to scan for moc'able files
    # We can't refer to the builders directly, we have to fetch them
    # as Environment attributes because that sets them up to be called
    # correctly later by our emitter.
    env.AppendUnique(PROGEMITTER =[AutomocStatic],
                     SHLIBEMITTER=[AutomocShared],
                     LIBEMITTER  =[AutomocStatic],
                    )

    # TODO: Does dbusxml2cpp need an adapter
    env.AddMethod(enable_modules, "EnableQt5Modules")

def enable_modules(self, modules, debug=False, crosscompiling=False) :
    import sys

    validModules = [
        # Qt Essentials
        'QtCore',
        'QtGui',
        'QtMultimedia',
        'QtMultimediaQuick_p',
        'QtMultimediaWidgets',
        'QtNetwork',
        'QtPlatformSupport',
        'QtQml',
        'QtQmlDevTools',
        'QtQuick',
        'QtQuickParticles',
        'QtSql',
        'QtQuickTest',
        'QtTest',
        'QtWebKit',
        'QtWebKitWidgets',
        'QtWidgets',
        # Qt Add-Ons
        'QtConcurrent',
        'QtDBus',
        'QtOpenGL',
        'QtPrintSupport',
        'QtDeclarative',
        'QtScript',
        'QtScriptTools',
        'QtSvg',
        'QtUiTools',
        'QtXml',
        'QtXmlPatterns',
        # Qt Tools
        'QtHelp',
        'QtDesigner',
        'QtDesignerComponents',
        # Other
        'QtCLucene',
        'QtConcurrent',
        'QtV8'
        ]
    pclessModules = [
    ]
    staticModules = [
    ]
    invalidModules=[]
    for module in modules:
        if module not in validModules :
            invalidModules.append(module)
    if invalidModules :
        raise Exception("Modules %s are not Qt5 modules. Valid Qt5 modules are: %s"% (
            str(invalidModules),str(validModules)))

    moduleDefines = {
        'QtScript'   : ['QT_SCRIPT_LIB'],
        'QtSvg'      : ['QT_SVG_LIB'],
        'QtSql'      : ['QT_SQL_LIB'],
        'QtXml'      : ['QT_XML_LIB'],
        'QtOpenGL'   : ['QT_OPENGL_LIB'],
        'QtGui'      : ['QT_GUI_LIB'],
        'QtNetwork'  : ['QT_NETWORK_LIB'],
        'QtCore'     : ['QT_CORE_LIB'],
        'QtWidgets'  : ['QT_WIDGETS_LIB'],
    }
    for module in modules :
        try : self.AppendUnique(CPPDEFINES=moduleDefines[module])
        except: pass
    debugSuffix = ''
    if sys.platform in ["darwin", "linux2", "linux"] and not crosscompiling :
        if debug : debugSuffix = '_debug'
        for module in modules :
            if module not in pclessModules : continue
            self.AppendUnique(LIBS=[module.replace('Qt','Qt5')+debugSuffix])
            self.AppendUnique(LIBPATH=[os.path.join("$QT5DIR","lib")])
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include")])
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include",module)])
        pcmodules = [module.replace('Qt','Qt5')+debugSuffix for module in modules if module not in pclessModules ]
        if 'Qt5DBus' in pcmodules:
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include","Qt5DBus")])
        if "Qt5Assistant" in pcmodules:
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include","Qt5Assistant")])
            pcmodules.remove("Qt5Assistant")
            pcmodules.append("Qt5AssistantClient")
        self.AppendUnique(RPATH=[os.path.join("$QT5DIR","lib")])
        self.ParseConfig('pkg-config %s --libs --cflags'% ' '.join(pcmodules))
        self["QT5_MOCCPPPATH"] = self["CPPPATH"]
        return
    if sys.platform == "win32" or crosscompiling :
        if crosscompiling:
            transformedQtdir = transformToWinePath(self['QT5DIR'])
            self['QT5_MOC'] = "QT5DIR=%s %s"%( transformedQtdir, self['QT5_MOC'])
        self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include")])
        try: modules.remove("QtDBus")
        except: pass
        if debug : debugSuffix = 'd'
        if "QtAssistant" in modules:
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include","QtAssistant")])
            modules.remove("QtAssistant")
            modules.append("QtAssistantClient")
        self.AppendUnique(LIBS=['qtmain'+debugSuffix])
        self.AppendUnique(LIBS=[lib.replace("Qt","Qt5")+debugSuffix for lib in modules if lib not in staticModules])
        self.PrependUnique(LIBS=[lib+debugSuffix for lib in modules if lib in staticModules])
        if 'QtOpenGL' in modules:
            self.AppendUnique(LIBS=['opengl32'])
        self.AppendUnique(CPPPATH=[ '$QT5DIR/include/'])
        self.AppendUnique(CPPPATH=[ '$QT5DIR/include/'+module for module in modules])
        if crosscompiling :
            self["QT5_MOCCPPPATH"] = [
                path.replace('$QT5DIR', transformedQtdir)
                    for path in self['CPPPATH'] ]
        else :
            self["QT5_MOCCPPPATH"] = self["CPPPATH"]
        self.AppendUnique(LIBPATH=[os.path.join('$QT5DIR','lib')])
        return
        
    """
    if sys.platform=="darwin" :
        # TODO: Test debug version on Mac
        self.AppendUnique(LIBPATH=[os.path.join('$QT5DIR','lib')])
        self.AppendUnique(LINKFLAGS="-F$QT5DIR/lib")
        self.AppendUnique(LINKFLAGS="-L$QT5DIR/lib") #TODO clean!
        if debug : debugSuffix = 'd'
        for module in modules :
#            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include")])
#            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include",module)])
# port qt5-mac:
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include", "qt5")])
            self.AppendUnique(CPPPATH=[os.path.join("$QT5DIR","include", "qt5", module)])
            if module in staticModules :
                self.AppendUnique(LIBS=[module+debugSuffix]) # TODO: Add the debug suffix
                self.AppendUnique(LIBPATH=[os.path.join("$QT5DIR","lib")])
            else :
#                self.Append(LINKFLAGS=['-framework', module])
# port qt5-mac:
                self.Append(LIBS=module)
        if 'QtOpenGL' in modules:
            self.AppendUnique(LINKFLAGS="-F/System/Library/Frameworks")
            self.Append(LINKFLAGS=['-framework', 'AGL']) #TODO ughly kludge to avoid quotes
            self.Append(LINKFLAGS=['-framework', 'OpenGL'])
        self["QT5_MOCCPPPATH"] = self["CPPPATH"]
        return
# This should work for mac but doesn't
#    env.AppendUnique(FRAMEWORKPATH=[os.path.join(env['QT5DIR'],'lib')])
#    env.AppendUnique(FRAMEWORKS=['QtCore','QtGui','QtOpenGL', 'AGL'])
    """

def exists(env):
    return _detect(env)