"""SCons.Environment Base class for construction Environments. These are the primary objects used to communicate dependency and construction information to the build engine. Keyword arguments supplied when the construction Environment is created are construction variables used to initialize the Environment """ # # __COPYRIGHT__ # # 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. # __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__" import copy import os import os.path import popen2 import string from UserDict import UserDict import SCons.Action import SCons.Builder from SCons.Debug import logInstanceCreation import SCons.Defaults import SCons.Errors import SCons.Node import SCons.Node.Alias import SCons.Node.FS import SCons.Node.Python import SCons.Platform import SCons.SConsign import SCons.Sig import SCons.Sig.MD5 import SCons.Sig.TimeStamp import SCons.Subst import SCons.Tool import SCons.Util import SCons.Warnings class _Null: pass _null = _Null CleanTargets = {} CalculatorArgs = {} # Pull UserError into the global name space for the benefit of # Environment().SourceSignatures(), which has some import statements # which seem to mess up its ability to reference SCons directly. UserError = SCons.Errors.UserError def installFunc(target, source, env): """Install a source file into a target using the function specified as the INSTALL construction variable.""" try: install = env['INSTALL'] except KeyError: raise SCons.Errors.UserError('Missing INSTALL construction variable.') return install(target[0].path, source[0].path, env) def installString(target, source, env): return env.subst_target_source(env['INSTALLSTR'], 0, target, source) installAction = SCons.Action.Action(installFunc, installString) InstallBuilder = SCons.Builder.Builder(action=installAction, name='InstallBuilder') def alias_builder(env, target, source): pass AliasBuilder = SCons.Builder.Builder(action = alias_builder, target_factory = SCons.Node.Alias.default_ans.Alias, source_factory = SCons.Node.FS.Entry, multi = 1, is_explicit = None, name='AliasBuilder') def our_deepcopy(x): """deepcopy lists and dictionaries, and just copy the reference for everything else.""" if SCons.Util.is_Dict(x): copy = {} for key in x.keys(): copy[key] = our_deepcopy(x[key]) elif SCons.Util.is_List(x): copy = map(our_deepcopy, x) try: copy = x.__class__(copy) except AttributeError: pass else: copy = x return copy def apply_tools(env, tools, toolpath): # Store the toolpath in the Environment. if toolpath is not None: env['toolpath'] = toolpath if not tools: return # Filter out null tools from the list. for tool in filter(None, tools): if SCons.Util.is_List(tool) or type(tool)==type(()): toolname = tool[0] toolargs = tool[1] # should be a dict of kw args tool = apply(env.Tool, [toolname], toolargs) else: env.Tool(tool) # These names are controlled by SCons; users should never set or override # them. This warning can optionally be turned off, but scons will still # ignore the illegal variable names even if it's off. reserved_construction_var_names = \ ['TARGET', 'TARGETS', 'SOURCE', 'SOURCES'] def copy_non_reserved_keywords(dict): result = our_deepcopy(dict) for k in result.keys(): if k in reserved_construction_var_names: SCons.Warnings.warn(SCons.Warnings.ReservedVariableWarning, "Ignoring attempt to set reserved variable `%s'" % k) del result[k] return result def _set_reserved(env, key, value): msg = "Ignoring attempt to set reserved variable `%s'" % key SCons.Warnings.warn(SCons.Warnings.ReservedVariableWarning, msg) def _set_BUILDERS(env, key, value): try: bd = env._dict[key] for k in bd.keys(): del bd[k] except KeyError: env._dict[key] = BuilderDict(kwbd, env) env._dict[key].update(value) def _set_SCANNERS(env, key, value): env._dict[key] = value env.scanner_map_delete() class BuilderWrapper: """Wrapper class that associates an environment with a Builder at instantiation.""" def __init__(self, env, builder): self.env = env self.builder = builder def __call__(self, target=None, source=_null, *args, **kw): if source is _null: source = target target = None if not target is None and not SCons.Util.is_List(target): target = [target] if not source is None and not SCons.Util.is_List(source): source = [source] return apply(self.builder, (self.env, target, source) + args, kw) # This allows a Builder to be executed directly # through the Environment to which it's attached. # In practice, we shouldn't need this, because # builders actually get executed through a Node. # But we do have a unit test for this, and can't # yet rule out that it would be useful in the # future, so leave it for now. def execute(self, **kw): kw['env'] = self.env apply(self.builder.execute, (), kw) class BuilderDict(UserDict): """This is a dictionary-like class used by an Environment to hold the Builders. We need to do this because every time someone changes the Builders in the Environment's BUILDERS dictionary, we must update the Environment's attributes.""" def __init__(self, dict, env): # Set self.env before calling the superclass initialization, # because it will end up calling our other methods, which will # need to point the values in this dictionary to self.env. self.env = env UserDict.__init__(self, dict) def __setitem__(self, item, val): UserDict.__setitem__(self, item, val) try: self.setenvattr(item, val) except AttributeError: # Have to catch this because sometimes __setitem__ gets # called out of __init__, when we don't have an env # attribute yet, nor do we want one! pass def setenvattr(self, item, val): """Set the corresponding environment attribute for this Builder. If the value is already a BuilderWrapper, we pull the builder out of it and make another one, so that making a copy of an existing BuilderDict is guaranteed separate wrappers for each Builder + Environment pair.""" try: builder = val.builder except AttributeError: builder = val setattr(self.env, item, BuilderWrapper(self.env, builder)) def __delitem__(self, item): UserDict.__delitem__(self, item) delattr(self.env, item) def update(self, dict): for i, v in dict.items(): self.__setitem__(i, v) class SubstitutionEnvironment: """Base class for different flavors of construction environments. This class contains a minimal set of methods that handle contruction variable expansion and conversion of strings to Nodes, which may or may not be actually useful as a stand-alone class. Which methods ended up in this class is pretty arbitrary right now. They're basically the ones which we've empirically determined are common to the different construction environment subclasses, and most of the others that use or touch the underlying dictionary of construction variables. Eventually, this class should contain all the methods that we determine are necessary for a "minimal" interface to the build engine. A full "native Python" SCons environment has gotten pretty heavyweight with all of the methods and Tools and construction variables we've jammed in there, so it would be nice to have a lighter weight alternative for interfaces that don't need all of the bells and whistles. (At some point, we'll also probably rename this class "Base," since that more reflects what we want this class to become, but because we've released comments that tell people to subclass Environment.Base to create their own flavors of construction environment, we'll save that for a future refactoring when this class actually becomes useful.) """ if SCons.Memoize.use_memoizer: __metaclass__ = SCons.Memoize.Memoized_Metaclass def __init__(self, **kw): """Initialization of an underlying SubstitutionEnvironment class. """ if __debug__: logInstanceCreation(self, 'Environment.SubstitutionEnvironment') self.fs = SCons.Node.FS.default_fs or SCons.Node.FS.FS() self.ans = SCons.Node.Alias.default_ans self.lookup_list = SCons.Node.arg2nodes_lookups self._dict = kw.copy() self._init_special() def _init_special(self): """Initial the dispatch table for special handling of special construction variables.""" self._special = {} for key in reserved_construction_var_names: self._special[key] = _set_reserved self._special['BUILDERS'] = _set_BUILDERS self._special['SCANNERS'] = _set_SCANNERS def __cmp__(self, other): return cmp(self._dict, other._dict) def __delitem__(self, key): "__cache_reset__" del self._dict[key] def __getitem__(self, key): return self._dict[key] def __setitem__(self, key, value): "__cache_reset__" special = self._special.get(key) if special: special(self, key, value) else: if not SCons.Util.is_valid_construction_var(key): raise SCons.Errors.UserError, "Illegal construction variable `%s'" % key self._dict[key] = value def get(self, key, default=None): "Emulates the get() method of dictionaries.""" return self._dict.get(key, default) def has_key(self, key): return self._dict.has_key(key) def items(self): return self._dict.items() def arg2nodes(self, args, node_factory=_null, lookup_list=_null): if node_factory is _null: node_factory = self.fs.File if lookup_list is _null: lookup_list = self.lookup_list if not args: return [] if SCons.Util.is_List(args): args = SCons.Util.flatten(args) else: args = [args] nodes = [] for v in args: if SCons.Util.is_String(v): n = None for l in lookup_list: n = l(v) if not n is None: break if not n is None: if SCons.Util.is_String(n): n = self.subst(n, raw=1) if node_factory: n = node_factory(n) if SCons.Util.is_List(n): nodes.extend(n) else: nodes.append(n) elif node_factory: v = node_factory(self.subst(v, raw=1)) if SCons.Util.is_List(v): nodes.extend(v) else: nodes.append(v) else: nodes.append(v) return nodes def gvars(self): return self._dict def lvars(self): return {} def subst(self, string, raw=0, target=None, source=None, conv=None): """Recursively interpolates construction variables from the Environment into the specified string, returning the expanded result. Construction variables are specified by a $ prefix in the string and begin with an initial underscore or alphabetic character followed by any number of underscores or alphanumeric characters. The construction variable names may be surrounded by curly braces to separate the name from trailing characters. """ gvars = self.gvars() lvars = self.lvars() lvars['__env__'] = self return SCons.Subst.scons_subst(string, self, raw, target, source, gvars, lvars, conv) def subst_kw(self, kw, raw=0, target=None, source=None): nkw = {} for k, v in kw.items(): k = self.subst(k, raw, target, source) if SCons.Util.is_String(v): v = self.subst(v, raw, target, source) nkw[k] = v return nkw def subst_list(self, string, raw=0, target=None, source=None, conv=None): """Calls through to SCons.Subst.scons_subst_list(). See the documentation for that function.""" gvars = self.gvars() lvars = self.lvars() lvars['__env__'] = self return SCons.Subst.scons_subst_list(string, self, raw, target, source, gvars, lvars, conv) def subst_path(self, path, target=None, source=None): """Substitute a path list, turning EntryProxies into Nodes and leaving Nodes (and other objects) as-is.""" if not SCons.Util.is_List(path): path = [path] def s(obj): """This is the "string conversion" routine that we have our substitutions use to return Nodes, not strings. This relies on the fact that an EntryProxy object has a get() method that returns the underlying Node that it wraps, which is a bit of architectural dependence that we might need to break or modify in the future in response to additional requirements.""" try: get = obj.get except AttributeError: pass else: obj = get() return obj r = [] for p in path: if SCons.Util.is_String(p): p = self.subst(p, target=target, source=source, conv=s) if SCons.Util.is_List(p): if len(p) == 1: p = p[0] else: # We have an object plus a string, or multiple # objects that we need to smush together. No choice # but to make them into a string. p = string.join(map(SCons.Util.to_String, p), '') else: p = s(p) r.append(p) return r subst_target_source = subst def backtick(self, command): try: popen2.Popen3 except AttributeError: (tochild, fromchild, childerr) = os.popen3(self.subst(command)) tochild.close() err = childerr.read() out = fromchild.read() fromchild.close() status = childerr.close() else: p = popen2.Popen3(command, 1) p.tochild.close() out = p.fromchild.read() err = p.childerr.read() status = p.wait() if err: import sys sys.stderr.write(err) if status: try: if os.WIFEXITED(status): status = os.WEXITSTATUS(status) except AttributeError: pass raise OSError("'%s' exited %s" % (command, status)) return out def Override(self, overrides): """ Produce a modified environment whose variables are overriden by the overrides dictionaries. "overrides" is a dictionary that will override the variables of this environment. This function is much more efficient than Copy() or creating a new Environment because it doesn't copy the construction environment dictionary, it just wraps the underlying construction environment, and doesn't even create a wrapper object if there are no overrides. """ if overrides: o = copy_non_reserved_keywords(overrides) overrides = {} for key, value in o.items(): overrides[key] = SCons.Subst.scons_subst_once(value, self, key) if overrides: env = OverrideEnvironment(self, overrides) return env else: return self def ParseFlags(self, *flags): """ Parse the set of flags and return a dict with the flags placed in the appropriate entry. The flags are treated as a typical set of command-line flags for a GNU-like toolchain and used to populate the entries in the dict immediately below. If one of the flag strings begins with a bang (exclamation mark), it is assumed to be a command and the rest of the string is executed; the result of that evaluation is then added to the dict. """ dict = { 'ASFLAGS' : [], 'CCFLAGS' : [], 'CPPDEFINES' : [], 'CPPFLAGS' : [], 'CPPPATH' : [], 'FRAMEWORKPATH' : [], 'FRAMEWORKS' : [], 'LIBPATH' : [], 'LIBS' : [], 'LINKFLAGS' : [], 'RPATH' : [], } # The use of the "me" parameter to provide our own name for # recursion is an egregious hack to support Python 2.1 and before. def do_parse(arg, me, self = self, dict = dict): # if arg is a sequence, recurse with each element if not arg: return if not SCons.Util.is_String(arg): for t in arg: me(t, me) return # if arg is a command, execute it if arg[0] == '!': arg = self.backtick(arg[1:]) # utility function to deal with -D option def append_define(name, dict = dict): t = string.split(name, '=') if len(t) == 1: dict['CPPDEFINES'].append(name) else: dict['CPPDEFINES'].append([t[0], string.join(t[1:], '=')]) # Loop through the flags and add them to the appropriate option. # This tries to strike a balance between checking for all possible # flags and keeping the logic to a finite size, so it doesn't # check for some that don't occur often. It particular, if the # flag is not known to occur in a config script and there's a way # of passing the flag to the right place (by wrapping it in a -W # flag, for example) we don't check for it. Note that most # preprocessor options are not handled, since unhandled options # are placed in CCFLAGS, so unless the preprocessor is invoked # separately, these flags will still get to the preprocessor. # Other options not currently handled: # -iqoutedir (preprocessor search path) # -u symbol (linker undefined symbol) # -s (linker strip files) # -static* (linker static binding) # -shared* (linker dynamic binding) # -symbolic (linker global binding) # -R dir (deprecated linker rpath) # IBM compilers may also accept -qframeworkdir=foo params = string.split(arg) append_next_arg_to = None # for multi-word args for arg in params: if append_next_arg_to: if append_next_arg_to == 'CPPDEFINES': append_define(arg) elif append_next_arg_to == '-include': t = ('-include', self.fs.File(arg)) dict['CCFLAGS'].append(t) elif append_next_arg_to == '-isysroot': t = ('-isysroot', arg) dict['CCFLAGS'].append(t) dict['LINKFLAGS'].append(t) elif append_next_arg_to == '-arch': t = ('-arch', arg) dict['CCFLAGS'].append(t) dict['LINKFLAGS'].append(t) else: dict[append_next_arg_to].append(arg) append_next_arg_to = None elif not arg[0] in ['-', '+']: dict['LIBS'].append(self.fs.File(arg)) elif arg[:2] == '-L': if arg[2:]: dict['LIBPATH'].append(arg[2:]) else: append_next_arg_to = 'LIBPATH' elif arg[:2] == '-l': if arg[2:]: dict['LIBS'].append(arg[2:]) else: append_next_arg_to = 'LIBS' elif arg[:2] == '-I': if arg[2:]: dict['CPPPATH'].append(arg[2:]) else: append_next_arg_to = 'CPPPATH' elif arg[:4] == '-Wa,': dict['ASFLAGS'].append(arg[4:]) dict['CCFLAGS'].append(arg) elif arg[:4] == '-Wl,': if arg[:11] == '-Wl,-rpath=': dict['RPATH'].append(arg[11:]) elif arg[:7] == '-Wl,-R,': dict['RPATH'].append(arg[7:]) elif arg[:6] == '-Wl,-R': dict['RPATH'].append(arg[6:]) else: dict['LINKFLAGS'].append(arg) elif arg[:4] == '-Wp,': dict['CPPFLAGS'].append(arg) elif arg[:2] == '-D': if arg[2:]: append_define(arg[2:]) else: appencd_next_arg_to = 'CPPDEFINES' elif arg == '-framework': append_next_arg_to = 'FRAMEWORKS' elif arg[:14] == '-frameworkdir=': dict['FRAMEWORKPATH'].append(arg[14:]) elif arg[:2] == '-F': if arg[2:]: dict['FRAMEWORKPATH'].append(arg[2:]) else: append_next_arg_to = 'FRAMEWORKPATH' elif arg == '-mno-cygwin': dict['CCFLAGS'].append(arg) dict['LINKFLAGS'].append(arg) elif arg == '-mwindows': dict['LINKFLAGS'].append(arg) elif arg == '-pthread': dict['CCFLAGS'].append(arg) dict['LINKFLAGS'].append(arg) elif arg[0] == '+': dict['CCFLAGS'].append(arg) dict['LINKFLAGS'].append(arg) elif arg in ['-include', '-isysroot', '-arch']: append_next_arg_to = arg else: dict['CCFLAGS'].append(arg) for arg in flags: do_parse(arg, do_parse) return dict def MergeFlags(self, args, unique=1): """ Merge the dict in args into the construction variables. If args is not a dict, it is converted into a dict using ParseFlags. If unique is not set, the flags are appended rather than merged. """ if not SCons.Util.is_Dict(args): args = self.ParseFlags(args) if not unique: apply(self.Append, (), args) return self for key, value in args.items(): if value == '': continue try: orig = self[key] except KeyError: orig = value else: if len(orig) == 0: orig = [] elif not SCons.Util.is_List(orig): orig = [orig] orig = orig + value t = [] if key[-4:] == 'PATH': ### keep left-most occurence for v in orig: if v not in t: t.append(v) else: ### keep right-most occurence orig.reverse() for v in orig: if v not in t: t.insert(0, v) self[key] = t return self class Base(SubstitutionEnvironment): """Base class for "real" construction Environments. These are the primary objects used to communicate dependency and construction information to the build engine. Keyword arguments supplied when the construction Environment is created are construction variables used to initialize the Environment. """ if SCons.Memoize.use_memoizer: __metaclass__ = SCons.Memoize.Memoized_Metaclass ####################################################################### # This is THE class for interacting with the SCons build engine, # and it contains a lot of stuff, so we're going to try to keep this # a little organized by grouping the methods. ####################################################################### ####################################################################### # Methods that make an Environment act like a dictionary. These have # the expected standard names for Python mapping objects. Note that # we don't actually make an Environment a subclass of UserDict for # performance reasons. Note also that we only supply methods for # dictionary functionality that we actually need and use. ####################################################################### def __init__(self, platform=None, tools=None, toolpath=None, options=None, **kw): """ Initialization of a basic SCons construction environment, including setting up special construction variables like BUILDER, PLATFORM, etc., and searching for and applying available Tools. Note that we do *not* call the underlying base class (SubsitutionEnvironment) initialization, because we need to initialize things in a very specific order that doesn't work with the much simpler base class initialization. """ if __debug__: logInstanceCreation(self, 'Environment.Base') self.fs = SCons.Node.FS.default_fs or SCons.Node.FS.FS() self.ans = SCons.Node.Alias.default_ans self.lookup_list = SCons.Node.arg2nodes_lookups self._dict = our_deepcopy(SCons.Defaults.ConstructionEnvironment) self._init_special() self._dict['BUILDERS'] = BuilderDict(self._dict['BUILDERS'], self) if platform is None: platform = self._dict.get('PLATFORM', None) if platform is None: platform = SCons.Platform.Platform() if SCons.Util.is_String(platform): platform = SCons.Platform.Platform(platform) self._dict['PLATFORM'] = str(platform) platform(self) # Apply the passed-in variables and customizable options to the # environment before calling the tools, because they may use # some of them during initialization. apply(self.Replace, (), kw) if options: options.Update(self) if tools is None: tools = self._dict.get('TOOLS', None) if tools is None: tools = ['default'] apply_tools(self, tools, toolpath) # Now re-apply the passed-in variables and customizable options # to the environment, since the values the user set explicitly # should override any values set by the tools. apply(self.Replace, (), kw) if options: options.Update(self) ####################################################################### # Utility methods that are primarily for internal use by SCons. # These begin with lower-case letters. ####################################################################### def get_builder(self, name): """Fetch the builder with the specified name from the environment. """ try: return self._dict['BUILDERS'][name] except KeyError: return None def get_calculator(self): "__cacheable__" try: module = self._calc_module c = apply(SCons.Sig.Calculator, (module,), CalculatorArgs) except AttributeError: # Note that we're calling get_calculator() here, so the # DefaultEnvironment() must have a _calc_module attribute # to avoid infinite recursion. c = SCons.Defaults.DefaultEnvironment().get_calculator() return c def get_factory(self, factory, default='File'): """Return a factory function for creating Nodes for this construction environment. __cacheable__ """ name = default try: is_node = issubclass(factory, SCons.Node.Node) except TypeError: # The specified factory isn't a Node itself--it's # most likely None, or possibly a callable. pass else: if is_node: # The specified factory is a Node (sub)class. Try to # return the FS method that corresponds to the Node's # name--that is, we return self.fs.Dir if they want a Dir, # self.fs.File for a File, etc. try: name = factory.__name__ except AttributeError: pass else: factory = None if not factory: # They passed us None, or we picked up a name from a specified # class, so return the FS method. (Note that we *don't* # use our own self.{Dir,File} methods because that would # cause env.subst() to be called twice on the file name, # interfering with files that have $$ in them.) factory = getattr(self.fs, name) return factory def _gsm(self): "__cacheable__" try: scanners = self._dict['SCANNERS'] except KeyError: return None sm = {} # Reverse the scanner list so that, if multiple scanners # claim they can scan the same suffix, earlier scanners # in the list will overwrite later scanners, so that # the result looks like a "first match" to the user. if not SCons.Util.is_List(scanners): scanners = [scanners] else: scanners = scanners[:] # copy so reverse() doesn't mod original scanners.reverse() for scanner in scanners: for k in scanner.get_skeys(self): sm[k] = scanner return sm def get_scanner(self, skey): """Find the appropriate scanner given a key (usually a file suffix). """ sm = self._gsm() try: return sm[skey] except (KeyError, TypeError): return None def _smd(self): "__reset_cache__" pass def scanner_map_delete(self, kw=None): """Delete the cached scanner map (if we need to). """ if not kw is None and not kw.has_key('SCANNERS'): return self._smd() def _update(self, dict): """Update an environment's values directly, bypassing the normal checks that occur when users try to set items. __cache_reset__ """ self._dict.update(dict) def use_build_signature(self): try: return self._build_signature except AttributeError: b = SCons.Defaults.DefaultEnvironment()._build_signature self._build_signature = b return b ####################################################################### # Public methods for manipulating an Environment. These begin with # upper-case letters. The essential characteristic of methods in # this section is that they do *not* have corresponding same-named # global functions. For example, a stand-alone Append() function # makes no sense, because Append() is all about appending values to # an Environment's construction variables. ####################################################################### def Append(self, **kw): """Append values to existing construction variables in an Environment. """ kw = copy_non_reserved_keywords(kw) for key, val in kw.items(): # It would be easier on the eyes to write this using # "continue" statements whenever we finish processing an item, # but Python 1.5.2 apparently doesn't let you use "continue" # within try:-except: blocks, so we have to nest our code. try: orig = self._dict[key] except KeyError: # No existing variable in the environment, so just set # it to the new value. self._dict[key] = val else: try: # Most straightforward: just try to add them # together. This will work in most cases, when the # original and new values are of compatible types. self._dict[key] = orig + val except TypeError: try: # Try to update a dictionary value with another. # If orig isn't a dictionary, it won't have an # update() method; if val isn't a dictionary, # it won't have a keys() method. Either way, # it's an AttributeError. orig.update(val) except AttributeError: try: # Check if the original is a list. add_to_orig = orig.append except AttributeError: # The original isn't a list, but the new # value is (by process of elimination), # so insert the original in the new value # (if there's one to insert) and replace # the variable with it. if orig: val.insert(0, orig) self._dict[key] = val else: # The original is a list, so append the new # value to it (if there's a value to append). if val: add_to_orig(val) self.scanner_map_delete(kw) def AppendENVPath(self, name, newpath, envname = 'ENV', sep = os.pathsep): """Append path elements to the path 'name' in the 'ENV' dictionary for this environment. Will only add any particular path once, and will normpath and normcase all paths to help assure this. This can also handle the case where the env variable is a list instead of a string. """ orig = '' if self._dict.has_key(envname) and self._dict[envname].has_key(name): orig = self._dict[envname][name] nv = SCons.Util.AppendPath(orig, newpath, sep) if not self._dict.has_key(envname): self._dict[envname] = {} self._dict[envname][name] = nv def AppendUnique(self, **kw): """Append values to existing construction variables in an Environment, if they're not already there. """ kw = copy_non_reserved_keywords(kw) for key, val in kw.items(): if not self._dict.has_key(key) or not self._dict[key]: self._dict[key] = val elif SCons.Util.is_Dict(self._dict[key]) and \ SCons.Util.is_Dict(val): self._dict[key].update(val) elif SCons.Util.is_List(val): dk = self._dict[key] if not SCons.Util.is_List(dk): dk = [dk] val = filter(lambda x, dk=dk: x not in dk, val) self._dict[key] = dk + val else: dk = self._dict[key] if SCons.Util.is_List(dk): # By elimination, val is not a list. Since dk is a # list, wrap val in a list first. if not val in dk: self._dict[key] = dk + [val] else: self._dict[key] = self._dict[key] + val self.scanner_map_delete(kw) def Copy(self, tools=[], toolpath=None, **kw): """Return a copy of a construction Environment. The copy is like a Python "deep copy"--that is, independent copies are made recursively of each objects--except that a reference is copied when an object is not deep-copyable (like a function). There are no references to any mutable objects in the original Environment. """ clone = copy.copy(self) clone._dict = our_deepcopy(self._dict) try: cbd = clone._dict['BUILDERS'] clone._dict['BUILDERS'] = BuilderDict(cbd, clone) except KeyError: pass apply_tools(clone, tools, toolpath) # Apply passed-in variables after the new tools. kw = copy_non_reserved_keywords(kw) new = {} for key, value in kw.items(): new[key] = SCons.Subst.scons_subst_once(value, self, key) apply(clone.Replace, (), new) if __debug__: logInstanceCreation(self, 'Environment.EnvironmentCopy') return clone def Detect(self, progs): """Return the first available program in progs. __cacheable__ """ if not SCons.Util.is_List(progs): progs = [ progs ] for prog in progs: path = self.WhereIs(prog) if path: return prog return None def Dictionary(self, *args): if not args: return self._dict dlist = map(lambda x, s=self: s._dict[x], args) if len(dlist) == 1: dlist = dlist[0] return dlist def Dump(self, key = None): """ Using the standard Python pretty printer, dump the contents of the scons build environment to stdout. If the key passed in is anything other than None, then that will be used as an index into the build environment dictionary and whatever is found there will be fed into the pretty printer. Note that this key is case sensitive. """ import pprint pp = pprint.PrettyPrinter(indent=2) if key: dict = self.Dictionary(key) else: dict = self.Dictionary() return pp.pformat(dict) def FindIxes(self, paths, prefix, suffix): """ Search a list of paths for something that matches the prefix and suffix. paths - the list of paths or nodes. prefix - construction variable for the prefix. suffix - construction variable for the suffix. """ suffix = self.subst('$'+suffix) prefix = self.subst('$'+prefix) for path in paths: dir,name = os.path.split(str(path)) if name[:len(prefix)] == prefix and name[-len(suffix):] == suffix: return path def ParseConfig(self, command, function=None, unique=1): """ Use the specified function to parse the output of the command in order to modify the current environment. The 'command' can be a string or a list of strings representing a command and its arguments. 'Function' is an optional argument that takes the environment, the output of the command, and the unique flag. If no function is specified, MergeFlags, which treats the output as the result of a typical 'X-config' command (i.e. gtk-config), will merge the output into the appropriate variables. """ if function is None: def parse_conf(env, cmd, unique=unique): return env.MergeFlags(cmd, unique) function = parse_conf if SCons.Util.is_List(command): command = string.join(command) command = self.subst(command) return function(self, self.backtick(command)) def ParseDepends(self, filename, must_exist=None, only_one=0): """ Parse a mkdep-style file for explicit dependencies. This is completely abusable, and should be unnecessary in the "normal" case of proper SCons configuration, but it may help make the transition from a Make hierarchy easier for some people to swallow. It can also be genuinely useful when using a tool that can write a .d file, but for which writing a scanner would be too complicated. """ filename = self.subst(filename) try: fp = open(filename, 'r') except IOError: if must_exist: raise return lines = SCons.Util.LogicalLines(fp).readlines() lines = filter(lambda l: l[0] != '#', lines) tdlist = [] for line in lines: try: target, depends = string.split(line, ':', 1) except (AttributeError, TypeError, ValueError): # Python 1.5.2 throws TypeError if line isn't a string, # Python 2.x throws AttributeError because it tries # to call line.split(). Either can throw ValueError # if the line doesn't split into two or more elements. pass else: tdlist.append((string.split(target), string.split(depends))) if only_one: targets = reduce(lambda x, y: x+y, map(lambda p: p[0], tdlist)) if len(targets) > 1: raise SCons.Errors.UserError, "More than one dependency target found in `%s': %s" % (filename, targets) for target, depends in tdlist: self.Depends(target, depends) def Platform(self, platform): platform = self.subst(platform) return SCons.Platform.Platform(platform)(self) def Prepend(self, **kw): """Prepend values to existing construction variables in an Environment. """ kw = copy_non_reserved_keywords(kw) for key, val in kw.items(): # It would be easier on the eyes to write this using # "continue" statements whenever we finish processing an item, # but Python 1.5.2 apparently doesn't let you use "continue" # within try:-except: blocks, so we have to nest our code. try: orig = self._dict[key] except KeyError: # No existing variable in the environment, so just set # it to the new value. self._dict[key] = val else: try: # Most straightforward: just try to add them # together. This will work in most cases, when the # original and new values are of compatible types. self._dict[key] = val + orig except TypeError: try: # Try to update a dictionary value with another. # If orig isn't a dictionary, it won't have an # update() method; if val isn't a dictionary, # it won't have a keys() method. Either way, # it's an AttributeError. orig.update(val) except AttributeError: try: # Check if the added value is a list. add_to_val = val.append except AttributeError: # The added value isn't a list, but the # original is (by process of elimination), # so insert the the new value in the original # (if there's one to insert). if val: orig.insert(0, val) else: # The added value is a list, so append # the original to it (if there's a value # to append). if orig: add_to_val(orig) self._dict[key] = val self.scanner_map_delete(kw) def PrependENVPath(self, name, newpath, envname = 'ENV', sep = os.pathsep): """Prepend path elements to the path 'name' in the 'ENV' dictionary for this environment. Will only add any particular path once, and will normpath and normcase all paths to help assure this. This can also handle the case where the env variable is a list instead of a string. """ orig = '' if self._dict.has_key(envname) and self._dict[envname].has_key(name): orig = self._dict[envname][name] nv = SCons.Util.PrependPath(orig, newpath, sep) if not self._dict.has_key(envname): self._dict[envname] = {} self._dict[envname][name] = nv def PrependUnique(self, **kw): """Append values to existing construction variables in an Environment, if they're not already there. """ kw = copy_non_reserved_keywords(kw) for key, val in kw.items(): if not self._dict.has_key(key) or not self._dict[key]: self._dict[key] = val elif SCons.Util.is_Dict(self._dict[key]) and \ SCons.Util.is_Dict(val): self._dict[key].update(val) elif SCons.Util.is_List(val): dk = self._dict[key] if not SCons.Util.is_List(dk): dk = [dk] val = filter(lambda x, dk=dk: x not in dk, val) self._dict[key] = val + dk else: dk = self._dict[key] if SCons.Util.is_List(dk): # By elimination, val is not a list. Since dk is a # list, wrap val in a list first. if not val in dk: self._dict[key] = [val] + dk else: self._dict[key] = val + dk self.scanner_map_delete(kw) def Replace(self, **kw): """Replace existing construction variables in an Environment with new construction variables and/or values. """ try: kwbd = our_deepcopy(kw['BUILDERS']) del kw['BUILDERS'] self.__setitem__('BUILDERS', kwbd) except KeyError: pass kw = copy_non_reserved_keywords(kw) self._update(our_deepcopy(kw)) self.scanner_map_delete(kw) def ReplaceIxes(self, path, old_prefix, old_suffix, new_prefix, new_suffix): """ Replace old_prefix with new_prefix and old_suffix with new_suffix. env - Environment used to interpolate variables. path - the path that will be modified. old_prefix - construction variable for the old prefix. old_suffix - construction variable for the old suffix. new_prefix - construction variable for the new prefix. new_suffix - construction variable for the new suffix. """ old_prefix = self.subst('$'+old_prefix) old_suffix = self.subst('$'+old_suffix) new_prefix = self.subst('$'+new_prefix) new_suffix = self.subst('$'+new_suffix) dir,name = os.path.split(str(path)) if name[:len(old_prefix)] == old_prefix: name = name[len(old_prefix):] if name[-len(old_suffix):] == old_suffix: name = name[:-len(old_suffix)] return os.path.join(dir, new_prefix+name+new_suffix) def SetDefault(self, **kw): for k in kw.keys(): if self._dict.has_key(k): del kw[k] apply(self.Replace, (), kw) def Tool(self, tool, toolpath=None, **kw): if SCons.Util.is_String(tool): tool = self.subst(tool) if toolpath is None: toolpath = self.get('toolpath', []) toolpath = map(self.subst, toolpath) tool = apply(SCons.Tool.Tool, (tool, toolpath), kw) tool(self) def WhereIs(self, prog, path=None, pathext=None, reject=[]): """Find prog in the path. __cacheable__ """ if path is None: try: path = self['ENV']['PATH'] except KeyError: pass elif SCons.Util.is_String(path): path = self.subst(path) if pathext is None: try: pathext = self['ENV']['PATHEXT'] except KeyError: pass elif SCons.Util.is_String(pathext): pathext = self.subst(pathext) path = SCons.Util.WhereIs(prog, path, pathext, reject) if path: return path return None ####################################################################### # Public methods for doing real "SCons stuff" (manipulating # dependencies, setting attributes on targets, etc.). These begin # with upper-case letters. The essential characteristic of methods # in this section is that they all *should* have corresponding # same-named global functions. ####################################################################### def Action(self, *args, **kw): def subst_string(a, self=self): if SCons.Util.is_String(a): a = self.subst(a) return a nargs = map(subst_string, args) nkw = self.subst_kw(kw) return apply(SCons.Action.Action, nargs, nkw) def AddPreAction(self, files, action): nodes = self.arg2nodes(files, self.fs.Entry) action = SCons.Action.Action(action) uniq = {} for executor in map(lambda n: n.get_executor(), nodes): uniq[executor] = 1 for executor in uniq.keys(): executor.add_pre_action(action) return nodes def AddPostAction(self, files, action): nodes = self.arg2nodes(files, self.fs.Entry) action = SCons.Action.Action(action) uniq = {} for executor in map(lambda n: n.get_executor(), nodes): uniq[executor] = 1 for executor in uniq.keys(): executor.add_post_action(action) return nodes def Alias(self, target, source=[], action=None, **kw): tlist = self.arg2nodes(target, self.ans.Alias) if not SCons.Util.is_List(source): source = [source] source = filter(None, source) if not action: if not source: # There are no source files and no action, so just # return a target list of classic Alias Nodes, without # any builder. The externally visible effect is that # this will make the wrapping Script.BuildTask class # say that there's "Nothing to be done" for this Alias, # instead of that it's "up to date." return tlist # No action, but there are sources. Re-call all the target # builders to add the sources to each target. result = [] for t in tlist: bld = t.get_builder(AliasBuilder) result.extend(bld(self, t, source)) return result nkw = self.subst_kw(kw) nkw.update({ 'action' : SCons.Action.Action(action), 'source_factory' : self.fs.Entry, 'multi' : 1, 'is_explicit' : None, }) bld = apply(SCons.Builder.Builder, (), nkw) # Apply the Builder separately to each target so that the Aliases # stay separate. If we did one "normal" Builder call with the # whole target list, then all of the target Aliases would be # associated under a single Executor. result = [] for t in tlist: # Calling the convert() method will cause a new Executor to be # created from scratch, so we have to explicitly initialize # it with the target's existing sources, plus our new ones, # so nothing gets lost. b = t.get_builder() if b is None or b is AliasBuilder: b = bld else: nkw['action'] = b.action + action b = apply(SCons.Builder.Builder, (), nkw) t.convert() result.extend(b(self, t, t.sources + source)) return result def AlwaysBuild(self, *targets): tlist = [] for t in targets: tlist.extend(self.arg2nodes(t, self.fs.File)) for t in tlist: t.set_always_build() return tlist def BuildDir(self, build_dir, src_dir, duplicate=1): build_dir = self.arg2nodes(build_dir, self.fs.Dir)[0] src_dir = self.arg2nodes(src_dir, self.fs.Dir)[0] self.fs.BuildDir(build_dir, src_dir, duplicate) def Builder(self, **kw): nkw = self.subst_kw(kw) return apply(SCons.Builder.Builder, [], nkw) def CacheDir(self, path): self.fs.CacheDir(self.subst(path)) def Clean(self, targets, files): global CleanTargets tlist = self.arg2nodes(targets, self.fs.Entry) flist = self.arg2nodes(files, self.fs.Entry) for t in tlist: try: CleanTargets[t].extend(flist) except KeyError: CleanTargets[t] = flist def Configure(self, *args, **kw): nargs = [self] if args: nargs = nargs + self.subst_list(args)[0] nkw = self.subst_kw(kw) nkw['_depth'] = kw.get('_depth', 0) + 1 try: nkw['custom_tests'] = self.subst_kw(nkw['custom_tests']) except KeyError: pass return apply(SCons.SConf.SConf, nargs, nkw) def Command(self, target, source, action, **kw): """Builds the supplied target files from the supplied source files using the supplied action. Action may be any type that the Builder constructor will accept for an action.""" bkw = { 'action' : action, 'target_factory' : self.fs.Entry, 'source_factory' : self.fs.Entry, } try: bkw['source_scanner'] = kw['source_scanner'] except KeyError: pass else: del kw['source_scanner'] bld = apply(SCons.Builder.Builder, (), bkw) return apply(bld, (self, target, source), kw) def Depends(self, target, dependency): """Explicity specify that 'target's depend on 'dependency'.""" tlist = self.arg2nodes(target, self.fs.Entry) dlist = self.arg2nodes(dependency, self.fs.Entry) for t in tlist: t.add_dependency(dlist) return tlist def Dir(self, name, *args, **kw): """ """ return apply(self.fs.Dir, (self.subst(name),) + args, kw) def NoClean(self, *targets): """Tags a target so that it will not be cleaned by -c""" tlist = [] for t in targets: tlist.extend(self.arg2nodes(t, self.fs.Entry)) for t in tlist: t.set_noclean() return tlist def Entry(self, name, *args, **kw): """ """ return apply(self.fs.Entry, (self.subst(name),) + args, kw) def Environment(self, **kw): return apply(SCons.Environment.Environment, [], self.subst_kw(kw)) def Execute(self, action, *args, **kw): """Directly execute an action through an Environment """ action = apply(self.Action, (action,) + args, kw) return action([], [], self) def File(self, name, *args, **kw): """ """ return apply(self.fs.File, (self.subst(name),) + args, kw) def FindFile(self, file, dirs): file = self.subst(file) nodes = self.arg2nodes(dirs, self.fs.Dir) return SCons.Node.FS.find_file(file, tuple(nodes)) def Flatten(self, sequence): return SCons.Util.flatten(sequence) def GetBuildPath(self, files): result = map(str, self.arg2nodes(files, self.fs.Entry)) if SCons.Util.is_List(files): return result else: return result[0] def Ignore(self, target, dependency): """Ignore a dependency.""" tlist = self.arg2nodes(target, self.fs.Entry) dlist = self.arg2nodes(dependency, self.fs.Entry) for t in tlist: t.add_ignore(dlist) return tlist def Install(self, dir, source): """Install specified files in the given directory.""" try: dnodes = self.arg2nodes(dir, self.fs.Dir) except TypeError: raise SCons.Errors.UserError, "Target `%s' of Install() is a file, but should be a directory. Perhaps you have the Install() arguments backwards?" % str(dir) try: sources = self.arg2nodes(source, self.fs.File) except TypeError: if SCons.Util.is_List(source): raise SCons.Errors.UserError, "Source `%s' of Install() contains one or more non-files. Install() source must be one or more files." % repr(map(str, source)) else: raise SCons.Errors.UserError, "Source `%s' of Install() is not a file. Install() source must be one or more files." % str(source) tgt = [] for dnode in dnodes: for src in sources: target = self.fs.File(src.name, dnode) tgt.extend(InstallBuilder(self, target, src)) return tgt def InstallAs(self, target, source): """Install sources as targets.""" sources = self.arg2nodes(source, self.fs.File) targets = self.arg2nodes(target, self.fs.File) result = [] for src, tgt in map(lambda x, y: (x, y), sources, targets): result.extend(InstallBuilder(self, tgt, src)) return result def Literal(self, string): return SCons.Subst.Literal(string) def Local(self, *targets): ret = [] for targ in targets: if isinstance(targ, SCons.Node.Node): targ.set_local() ret.append(targ) else: for t in self.arg2nodes(targ, self.fs.Entry): t.set_local() ret.append(t) return ret def Precious(self, *targets): tlist = [] for t in targets: tlist.extend(self.arg2nodes(t, self.fs.Entry)) for t in tlist: t.set_precious() return tlist def Repository(self, *dirs, **kw): dirs = self.arg2nodes(list(dirs), self.fs.Dir) apply(self.fs.Repository, dirs, kw) def Scanner(self, *args, **kw): nargs = [] for arg in args: if SCons.Util.is_String(arg): arg = self.subst(arg) nargs.append(arg) nkw = self.subst_kw(kw) return apply(SCons.Scanner.Scanner, nargs, nkw) def SConsignFile(self, name=".sconsign", dbm_module=None): if not name is None: name = self.subst(name) if not os.path.isabs(name): name = os.path.join(str(self.fs.SConstruct_dir), name) SCons.SConsign.File(name, dbm_module) def SideEffect(self, side_effect, target): """Tell scons that side_effects are built as side effects of building targets.""" side_effects = self.arg2nodes(side_effect, self.fs.Entry) targets = self.arg2nodes(target, self.fs.Entry) for side_effect in side_effects: if side_effect.multiple_side_effect_has_builder(): raise SCons.Errors.UserError, "Multiple ways to build the same target were specified for: %s" % str(side_effect) side_effect.add_source(targets) side_effect.side_effect = 1 self.Precious(side_effect) for target in targets: target.side_effects.append(side_effect) return side_effects def SourceCode(self, entry, builder): """Arrange for a source code builder for (part of) a tree.""" entries = self.arg2nodes(entry, self.fs.Entry) for entry in entries: entry.set_src_builder(builder) return entries def SourceSignatures(self, type): type = self.subst(type) if type == 'MD5': import SCons.Sig.MD5 self._calc_module = SCons.Sig.MD5 elif type == 'timestamp': import SCons.Sig.TimeStamp self._calc_module = SCons.Sig.TimeStamp else: raise UserError, "Unknown source signature type '%s'"%type def Split(self, arg): """This function converts a string or list into a list of strings or Nodes. This makes things easier for users by allowing files to be specified as a white-space separated list to be split. The input rules are: - A single string containing names separated by spaces. These will be split apart at the spaces. - A single Node instance - A list containing either strings or Node instances. Any strings in the list are not split at spaces. In all cases, the function returns a list of Nodes and strings.""" if SCons.Util.is_List(arg): return map(self.subst, arg) elif SCons.Util.is_String(arg): return string.split(self.subst(arg)) else: return [self.subst(arg)] def TargetSignatures(self, type): type = self.subst(type) if type == 'build': self._build_signature = 1 elif type == 'content': self._build_signature = 0 else: raise SCons.Errors.UserError, "Unknown target signature type '%s'"%type def Value(self, value): """ """ return SCons.Node.Python.Value(value) class OverrideEnvironment(Base): """A proxy that overrides variables in a wrapped construction environment by returning values from an overrides dictionary in preference to values from the underlying subject environment. This is a lightweight (I hope) proxy that passes through most use of attributes to the underlying Environment.Base class, but has just enough additional methods defined to act like a real construction environment with overridden values. It can wrap either a Base construction environment, or another OverrideEnvironment, which can in turn nest arbitrary OverrideEnvironments... Note that we do *not* call the underlying base class (SubsitutionEnvironment) initialization, because we get most of those from proxying the attributes of the subject construction environment. But because we subclass SubstitutionEnvironment, this class also has inherited arg2nodes() and subst*() methods; those methods can't be proxied because they need *this* object's methods to fetch the values from the overrides dictionary. """ if SCons.Memoize.use_memoizer: __metaclass__ = SCons.Memoize.Memoized_Metaclass def __init__(self, subject, overrides={}): if __debug__: logInstanceCreation(self, 'Environment.OverrideEnvironment') self.__dict__['__subject'] = subject self.__dict__['overrides'] = overrides # Methods that make this class act like a proxy. def __getattr__(self, name): return getattr(self.__dict__['__subject'], name) def __setattr__(self, name, value): return setattr(self.__dict__['__subject'], name, value) # Methods that make this class act like a dictionary. def __getitem__(self, key): try: return self.__dict__['overrides'][key] except KeyError: return self.__dict__['__subject'].__getitem__(key) def __setitem__(self, key, value): if not SCons.Util.is_valid_construction_var(key): raise SCons.Errors.UserError, "Illegal construction variable `%s'" % key self.__dict__['overrides'][key] = value def __delitem__(self, key): try: del self.__dict__['overrides'][key] except KeyError: deleted = 0 else: deleted = 1 try: result = self.__dict__['__subject'].__delitem__(key) except KeyError: if not deleted: raise result = None return result def get(self, key, default=None): """Emulates the get() method of dictionaries.""" try: return self.__dict__['overrides'][key] except KeyError: return self.__dict__['__subject'].get(key, default) def has_key(self, key): try: self.__dict__['overrides'][key] return 1 except KeyError: return self.__dict__['__subject'].has_key(key) def Dictionary(self): """Emulates the items() method of dictionaries.""" d = self.__dict__['__subject'].Dictionary().copy() d.update(self.__dict__['overrides']) return d def items(self): """Emulates the items() method of dictionaries.""" return self.Dictionary().items() # Overridden private construction environment methods. def _update(self, dict): """Update an environment's values directly, bypassing the normal checks that occur when users try to set items. """ self.__dict__['overrides'].update(dict) def gvars(self): return self.__dict__['__subject'].gvars() def lvars(self): lvars = self.__dict__['__subject'].lvars() lvars.update(self.__dict__['overrides']) return lvars # Overridden public construction environment methods. def Replace(self, **kw): kw = copy_non_reserved_keywords(kw) self.__dict__['overrides'].update(our_deepcopy(kw)) # The entry point that will be used by the external world # to refer to a construction environment. This allows the wrapper # interface to extend a construction environment for its own purposes # by subclassing SCons.Environment.Base and then assigning the # class to SCons.Environment.Environment. Environment = Base # An entry point for returning a proxy subclass instance that overrides # the subst*() methods so they don't actually perform construction # variable substitution. This is specifically intended to be the shim # layer in between global function calls (which don't want construction # variable substitution) and the DefaultEnvironment() (which would # substitute variables if left to its own devices).""" # # We have to wrap this in a function that allows us to delay definition of # the class until it's necessary, so that when it subclasses Environment # it will pick up whatever Environment subclass the wrapper interface # might have assigned to SCons.Environment.Environment. def NoSubstitutionProxy(subject): class _NoSubstitutionProxy(Environment): def __init__(self, subject): self.__dict__['__subject'] = subject def __getattr__(self, name): return getattr(self.__dict__['__subject'], name) def __setattr__(self, name, value): return setattr(self.__dict__['__subject'], name, value) def raw_to_mode(self, dict): try: raw = dict['raw'] except KeyError: pass else: del dict['raw'] dict['mode'] = raw def subst(self, string, *args, **kwargs): return string def subst_kw(self, kw, *args, **kwargs): return kw def subst_list(self, string, *args, **kwargs): nargs = (string, self,) + args nkw = kwargs.copy() nkw['gvars'] = {} self.raw_to_mode(nkw) return apply(SCons.Subst.scons_subst_list, nargs, nkw) def subst_target_source(self, string, *args, **kwargs): nargs = (string, self,) + args nkw = kwargs.copy() nkw['gvars'] = {} self.raw_to_mode(nkw) return apply(SCons.Subst.scons_subst, nargs, nkw) return _NoSubstitutionProxy(subject) if SCons.Memoize.use_old_memoization(): _Base = Base class Base(SCons.Memoize.Memoizer, _Base): def __init__(self, *args, **kw): SCons.Memoize.Memoizer.__init__(self) apply(_Base.__init__, (self,)+args, kw) Environment = Base