# MIT License
#
# Copyright 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.
"""SCons string substitution."""
import collections
import re
from inspect import signature, Parameter
from typing import Optional
import SCons.Errors
from SCons.Util import is_String, is_Sequence
# Indexed by the SUBST_* constants below.
_strconv = [
SCons.Util.to_String_for_subst,
SCons.Util.to_String_for_subst,
SCons.Util.to_String_for_signature,
]
AllowableExceptions = (IndexError, NameError)
[docs]
def SetAllowableExceptions(*excepts) -> None:
global AllowableExceptions
AllowableExceptions = [_f for _f in excepts if _f]
[docs]
def raise_exception(exception, target, s):
name = exception.__class__.__name__
msg = "%s `%s' trying to evaluate `%s'" % (name, exception, s)
if target:
raise SCons.Errors.BuildError(target[0], msg)
else:
raise SCons.Errors.UserError(msg)
[docs]
class Literal:
"""A wrapper for a string. If you use this object wrapped
around a string, then it will be interpreted as literal.
When passed to the command interpreter, all special
characters will be escaped."""
def __init__(self, lstr) -> None:
self.lstr = lstr
def __str__(self) -> str:
return self.lstr
[docs]
def escape(self, escape_func):
return escape_func(self.lstr)
[docs]
def for_signature(self):
return self.lstr
[docs]
def is_literal(self) -> bool:
return True
def __eq__(self, other):
if not isinstance(other, Literal):
return False
return self.lstr == other.lstr
def __neq__(self, other) -> bool:
return not self.__eq__(other)
def __hash__(self):
return hash(self.lstr)
[docs]
class SpecialAttrWrapper:
"""This is a wrapper for what we call a 'Node special attribute.'
This is any of the attributes of a Node that we can reference from
Environment variable substitution, such as $TARGET.abspath or
$SOURCES[1].filebase. We implement the same methods as Literal
so we can handle special characters, plus a for_signature method,
such that we can return some canonical string during signature
calculation to avoid unnecessary rebuilds."""
def __init__(self, lstr, for_signature=None) -> None:
"""The for_signature parameter, if supplied, will be the
canonical string we return from for_signature(). Else
we will simply return lstr."""
self.lstr = lstr
if for_signature:
self.forsig = for_signature
else:
self.forsig = lstr
def __str__(self) -> str:
return self.lstr
[docs]
def escape(self, escape_func):
return escape_func(self.lstr)
[docs]
def for_signature(self):
return self.forsig
[docs]
def is_literal(self) -> bool:
return True
[docs]
def quote_spaces(arg):
"""Generic function for putting double quotes around any string that
has white space in it."""
if ' ' in arg or '\t' in arg:
return '"%s"' % arg
else:
return str(arg)
[docs]
class CmdStringHolder(collections.UserString):
"""This is a special class used to hold strings generated by
scons_subst() and scons_subst_list(). It defines a special method
escape(). When passed a function with an escape algorithm for a
particular platform, it will return the contained string with the
proper escape sequences inserted.
"""
def __init__(self, cmd, literal=None) -> None:
super().__init__(cmd)
self.literal = literal
[docs]
def is_literal(self) -> bool:
return self.literal
[docs]
def escape(self, escape_func, quote_func=quote_spaces):
"""Escape the string with the supplied function. The
function is expected to take an arbitrary string, then
return it with all special characters escaped and ready
for passing to the command interpreter.
After calling this function, the next call to str() will
return the escaped string.
"""
if self.is_literal():
return escape_func(self.data)
elif ' ' in self.data or '\t' in self.data:
return quote_func(self.data)
else:
return self.data
[docs]
def escape_list(mylist, escape_func):
"""Escape a list of arguments by running the specified escape_func
on every object in the list that has an escape() method."""
def escape(obj, escape_func=escape_func):
try:
e = obj.escape
except AttributeError:
return obj
else:
return e(escape_func)
return list(map(escape, mylist))
[docs]
class NLWrapper:
"""A wrapper class that delays turning a list of sources or targets
into a NodeList until it's needed. The specified function supplied
when the object is initialized is responsible for turning raw nodes
into proxies that implement the special attributes like .abspath,
.source, etc. This way, we avoid creating those proxies just
"in case" someone is going to use $TARGET or the like, and only
go through the trouble if we really have to.
In practice, this might be a wash performance-wise, but it's a little
cleaner conceptually...
"""
def __init__(self, list, func) -> None:
self.list = list
self.func = func
[docs]
def _return_nodelist(self):
return self.nodelist
[docs]
def _gen_nodelist(self):
mylist = self.list
if mylist is None:
mylist = []
elif not is_Sequence(mylist):
mylist = [mylist]
# The map(self.func) call is what actually turns
# a list into appropriate proxies.
self.nodelist = SCons.Util.NodeList(list(map(self.func, mylist)))
self._create_nodelist = self._return_nodelist
return self.nodelist
_create_nodelist = _gen_nodelist
[docs]
class Targets_or_Sources(collections.UserList):
"""A class that implements $TARGETS or $SOURCES expansions by in turn
wrapping a NLWrapper. This class handles the different methods used
to access the list, calling the NLWrapper to create proxies on demand.
Note that we subclass collections.UserList purely so that the
is_Sequence() function will identify an object of this class as
a list during variable expansion. We're not really using any
collections.UserList methods in practice.
"""
def __init__(self, nl) -> None:
self.nl = nl
def __getattr__(self, attr):
nl = self.nl._create_nodelist()
return getattr(nl, attr)
def __getitem__(self, i):
nl = self.nl._create_nodelist()
return nl[i]
def __str__(self) -> str:
nl = self.nl._create_nodelist()
return str(nl)
def __repr__(self) -> str:
nl = self.nl._create_nodelist()
return repr(nl)
[docs]
class Target_or_Source:
"""A class that implements $TARGET or $SOURCE expansions by in turn
wrapping a NLWrapper. This class handles the different methods used
to access an individual proxy Node, calling the NLWrapper to create
a proxy on demand.
"""
def __init__(self, nl) -> None:
self.nl = nl
def __getattr__(self, attr):
nl = self.nl._create_nodelist()
try:
nl0 = nl[0]
except IndexError:
# If there is nothing in the list, then we have no attributes to
# pass through, so raise AttributeError for everything.
raise AttributeError("NodeList has no attribute: %s" % attr)
return getattr(nl0, attr)
def __str__(self) -> str:
nl = self.nl._create_nodelist()
if nl:
return str(nl[0])
return ''
def __repr__(self) -> str:
nl = self.nl._create_nodelist()
if nl:
return repr(nl[0])
return ''
[docs]
class NullNodeList(SCons.Util.NullSeq):
def __call__(self, *args, **kwargs) -> str: return ''
def __str__(self) -> str: return ''
NullNodesList = NullNodeList()
[docs]
def subst_dict(target, source):
"""Create a dictionary for substitution of special
construction variables.
This translates the following special arguments:
target - the target (object or array of objects),
used to generate the TARGET and TARGETS
construction variables
source - the source (object or array of objects),
used to generate the SOURCES and SOURCE
construction variables
"""
dict = {}
if target:
def get_tgt_subst_proxy(thing):
try:
subst_proxy = thing.get_subst_proxy()
except AttributeError:
subst_proxy = thing # probably a string, just return it
return subst_proxy
tnl = NLWrapper(target, get_tgt_subst_proxy)
dict['TARGETS'] = Targets_or_Sources(tnl)
dict['TARGET'] = Target_or_Source(tnl)
# This is a total cheat, but hopefully this dictionary goes
# away soon anyway. We just let these expand to $TARGETS
# because that's "good enough" for the use of ToolSurrogates
# (see test/ToolSurrogate.py) to generate documentation.
dict['CHANGED_TARGETS'] = '$TARGETS'
dict['UNCHANGED_TARGETS'] = '$TARGETS'
else:
dict['TARGETS'] = NullNodesList
dict['TARGET'] = NullNodesList
if source:
def get_src_subst_proxy(node):
try:
rfile = node.rfile
except AttributeError:
pass
else:
node = rfile()
try:
return node.get_subst_proxy()
except AttributeError:
return node # probably a String, just return it
snl = NLWrapper(source, get_src_subst_proxy)
dict['SOURCES'] = Targets_or_Sources(snl)
dict['SOURCE'] = Target_or_Source(snl)
# This is a total cheat, but hopefully this dictionary goes
# away soon anyway. We just let these expand to $TARGETS
# because that's "good enough" for the use of ToolSurrogates
# (see test/ToolSurrogate.py) to generate documentation.
dict['CHANGED_SOURCES'] = '$SOURCES'
dict['UNCHANGED_SOURCES'] = '$SOURCES'
else:
dict['SOURCES'] = NullNodesList
dict['SOURCE'] = NullNodesList
return dict
_callable_args_set = {'target', 'source', 'env', 'for_signature'}
[docs]
class StringSubber:
"""A class to construct the results of a scons_subst() call.
This binds a specific construction environment, mode, target and
source with two methods (substitute() and expand()) that handle
the expansion.
"""
def __init__(self, env, mode, conv, gvars) -> None:
self.env = env
self.mode = mode
self.conv = conv
self.gvars = gvars
[docs]
def expand(self, s, lvars):
"""Expand a single "token" as necessary, returning an
appropriate string containing the expansion.
This handles expanding different types of things (strings,
lists, callables) appropriately. It calls the wrapper
substitute() method to re-expand things as necessary, so that
the results of expansions of side-by-side strings still get
re-evaluated separately, not smushed together.
"""
if is_String(s):
try:
s0, s1 = s[:2]
except (IndexError, ValueError):
return s
if s0 != '$':
return s
if s1 == '$':
# In this case keep the double $'s which we'll later
# swap for a single dollar sign as we need to retain
# this information to properly avoid matching "$("" when
# the actual text was "$$("" (or "$)"" when "$$)"" )
return '$$'
elif s1 in '()':
return s
else:
key = s[1:]
if key[0] == '{' or '.' in key:
if key[0] == '{':
key = key[1:-1]
# Store for error messages if we fail to expand the
# value
old_s = s
s = None
if key in lvars:
s = lvars[key]
elif key in self.gvars:
s = self.gvars[key]
else:
try:
s = eval(key, self.gvars, lvars)
except KeyboardInterrupt:
raise
except Exception as e:
if e.__class__ in AllowableExceptions:
return ''
raise_exception(e, lvars['TARGETS'], old_s)
if s is None and NameError not in AllowableExceptions:
raise_exception(NameError(key), lvars['TARGETS'], old_s)
elif s is None:
return ''
# Before re-expanding the result, handle
# recursive expansion by copying the local
# variable dictionary and overwriting a null
# string for the value of the variable name
# we just expanded.
#
# This could potentially be optimized by only
# copying lvars when s contains more expansions,
# but lvars is usually supposed to be pretty
# small, and deeply nested variable expansions
# are probably more the exception than the norm,
# so it should be tolerable for now.
lv = lvars.copy()
var = key.split('.')[0]
lv[var] = ''
return self.substitute(s, lv)
elif is_Sequence(s):
def func(l, conv=self.conv, substitute=self.substitute, lvars=lvars):
return conv(substitute(l, lvars))
return list(map(func, s))
elif callable(s):
# SCons has the unusual Null class where any __getattr__ call returns it's self,
# which does not work the signature module, and the Null class returns an empty
# string if called on, so we make an exception in this condition for Null class
# Also allow callables where the only non default valued args match the expected defaults
# this should also allow functools.partial's to work.
if isinstance(s, SCons.Util.Null) or {k for k, v in signature(s).parameters.items() if
k in _callable_args_set or v.default == Parameter.empty} == _callable_args_set:
s = s(target=lvars['TARGETS'],
source=lvars['SOURCES'],
env=self.env,
for_signature=(self.mode == SUBST_SIG))
else:
# This probably indicates that it's a callable
# object that doesn't match our calling arguments
# (like an Action).
if self.mode == SUBST_RAW:
return s
s = self.conv(s)
return self.substitute(s, lvars)
elif s is None:
return ''
else:
return s
[docs]
def substitute(self, args, lvars):
"""Substitute expansions in an argument or list of arguments.
This serves as a wrapper for splitting up a string into
separate tokens.
"""
def sub_match(match):
return self.conv(self.expand(match.group(1), lvars))
if is_String(args) and not isinstance(args, CmdStringHolder):
args = str(args) # In case it's a UserString.
try:
result = _dollar_exps.sub(sub_match, args)
except TypeError:
# If the internal conversion routine doesn't return
# strings (it could be overridden to return Nodes, for
# example), then the 1.5.2 re module will throw this
# exception. Back off to a slower, general-purpose
# algorithm that works for all data types.
args = _separate_args.findall(args)
result = []
for a in args:
result.append(self.conv(self.expand(a, lvars)))
if len(result) == 1:
result = result[0]
else:
result = ''.join(map(str, result))
return result
else:
return self.expand(args, lvars)
[docs]
class ListSubber(collections.UserList):
"""A class to construct the results of a scons_subst_list() call.
Like StringSubber, this class binds a specific construction
environment, mode, target and source with two methods
(substitute() and expand()) that handle the expansion.
In addition, however, this class is used to track the state of
the result(s) we're gathering so we can do the appropriate thing
whenever we have to append another word to the result--start a new
line, start a new word, append to the current word, etc. We do
this by setting the "append" attribute to the right method so
that our wrapper methods only need ever call ListSubber.append(),
and the rest of the object takes care of doing the right thing
internally.
"""
def __init__(self, env, mode, conv, gvars) -> None:
super().__init__([])
self.env = env
self.mode = mode
self.conv = conv
self.gvars = gvars
if self.mode == SUBST_RAW:
self.add_strip = lambda x: self.append(x)
else:
self.add_strip = lambda x: None
self.in_strip = None
self.next_line()
[docs]
def expanded(self, s) -> bool:
"""Determines if the string s requires further expansion.
Due to the implementation of ListSubber expand will call
itself 2 additional times for an already expanded string. This
method is used to determine if a string is already fully
expanded and if so exit the loop early to prevent these
recursive calls.
"""
if not is_String(s) or isinstance(s, CmdStringHolder):
return False
s = str(s) # in case it's a UserString
return _separate_args.findall(s) is None
[docs]
def expand(self, s, lvars, within_list):
"""Expand a single "token" as necessary, appending the
expansion to the current result.
This handles expanding different types of things (strings,
lists, callables) appropriately. It calls the wrapper
substitute() method to re-expand things as necessary, so that
the results of expansions of side-by-side strings still get
re-evaluated separately, not smushed together.
"""
if is_String(s):
try:
s0, s1 = s[:2]
except (IndexError, ValueError):
self.append(s)
return
if s0 != '$':
self.append(s)
return
if s1 == '$':
self.append('$')
elif s1 == '(':
self.open_strip('$(')
elif s1 == ')':
self.close_strip('$)')
else:
key = s[1:]
if key[0] == '{' or key.find('.') >= 0:
if key[0] == '{':
key = key[1:-1]
# Store for error messages if we fail to expand the
# value
old_s = s
s = None
if key in lvars:
s = lvars[key]
elif key in self.gvars:
s = self.gvars[key]
else:
try:
s = eval(key, self.gvars, lvars)
except KeyboardInterrupt:
raise
except Exception as e:
if e.__class__ in AllowableExceptions:
return
raise_exception(e, lvars['TARGETS'], old_s)
if s is None and NameError not in AllowableExceptions:
raise_exception(NameError(), lvars['TARGETS'], old_s)
elif s is None:
return
# If the string is already full expanded there's no
# need to continue recursion.
if self.expanded(s):
self.append(s)
return
# Before re-expanding the result, handle
# recursive expansion by copying the local
# variable dictionary and overwriting a null
# string for the value of the variable name
# we just expanded.
lv = lvars.copy()
var = key.split('.')[0]
lv[var] = ''
self.substitute(s, lv, 0)
self.this_word()
elif is_Sequence(s):
for a in s:
self.substitute(a, lvars, 1)
self.next_word()
elif callable(s):
# SCons has the unusual Null class where any __getattr__ call returns it's self,
# which does not work the signature module, and the Null class returns an empty
# string if called on, so we make an exception in this condition for Null class
# Also allow callables where the only non default valued args match the expected defaults
# this should also allow functools.partial's to work.
if isinstance(s, SCons.Util.Null) or {k for k, v in signature(s).parameters.items() if
k in _callable_args_set or v.default == Parameter.empty} == _callable_args_set:
s = s(target=lvars['TARGETS'],
source=lvars['SOURCES'],
env=self.env,
for_signature=(self.mode != SUBST_CMD))
else:
# This probably indicates that it's a callable
# object that doesn't match our calling arguments
# (like an Action).
if self.mode == SUBST_RAW:
self.append(s)
return
s = self.conv(s)
self.substitute(s, lvars, within_list)
elif s is None:
self.this_word()
else:
self.append(s)
[docs]
def substitute(self, args, lvars, within_list) -> None:
"""Substitute expansions in an argument or list of arguments.
This serves as a wrapper for splitting up a string into
separate tokens.
"""
if is_String(args) and not isinstance(args, CmdStringHolder):
args = str(args) # In case it's a UserString.
args = _separate_args.findall(args)
for a in args:
if a[0] in ' \t\n\r\f\v':
if '\n' in a:
self.next_line()
elif within_list:
self.append(a)
else:
self.next_word()
else:
self.expand(a, lvars, within_list)
else:
self.expand(args, lvars, within_list)
[docs]
def next_line(self) -> None:
"""Arrange for the next word to start a new line. This
is like starting a new word, except that we have to append
another line to the result."""
collections.UserList.append(self, [])
self.next_word()
[docs]
def this_word(self) -> None:
"""Arrange for the next word to append to the end of the
current last word in the result."""
self.append = self.add_to_current_word
[docs]
def next_word(self) -> None:
"""Arrange for the next word to start a new word."""
self.append = self.add_new_word
[docs]
def add_to_current_word(self, x) -> None:
"""Append the string x to the end of the current last word
in the result. If that is not possible, then just add
it as a new word. Make sure the entire concatenated string
inherits the object attributes of x (in particular, the
escape function) by wrapping it as CmdStringHolder."""
if not self.in_strip or self.mode != SUBST_SIG:
try:
current_word = self[-1][-1]
except IndexError:
self.add_new_word(x)
else:
# All right, this is a hack and it should probably
# be refactored out of existence in the future.
# The issue is that we want to smoosh words together
# and make one file name that gets escaped if
# we're expanding something like foo$EXTENSION,
# but we don't want to smoosh them together if
# it's something like >$TARGET, because then we'll
# treat the '>' like it's part of the file name.
# So for now, just hard-code looking for the special
# command-line redirection characters...
try:
last_char = str(current_word)[-1]
except IndexError:
last_char = '\0'
if last_char in '<>|':
self.add_new_word(x)
else:
y = current_word + x
# We used to treat a word appended to a literal
# as a literal itself, but this caused problems
# with interpreting quotes around space-separated
# targets on command lines. Removing this makes
# none of the "substantive" end-to-end tests fail,
# so we'll take this out but leave it commented
# for now in case there's a problem not covered
# by the test cases and we need to resurrect this.
#literal1 = self.literal(self[-1][-1])
#literal2 = self.literal(x)
y = self.conv(y)
if is_String(y):
#y = CmdStringHolder(y, literal1 or literal2)
y = CmdStringHolder(y, None)
self[-1][-1] = y
[docs]
def add_new_word(self, x) -> None:
if not self.in_strip or self.mode != SUBST_SIG:
literal = self.literal(x)
x = self.conv(x)
if is_String(x):
x = CmdStringHolder(x, literal)
self[-1].append(x)
self.append = self.add_to_current_word
[docs]
def literal(self, x):
try:
l = x.is_literal
except AttributeError:
return None
else:
return l()
[docs]
def open_strip(self, x) -> None:
"""Handle the "open strip" $( token."""
self.add_strip(x)
self.in_strip = 1
[docs]
def close_strip(self, x) -> None:
"""Handle the "close strip" $) token."""
self.add_strip(x)
self.in_strip = None
# Constants for the "mode" parameter to scons_subst_list() and
# scons_subst(). SUBST_RAW gives the raw command line. SUBST_CMD
# gives a command line suitable for passing to a shell. SUBST_SIG
# gives a command line appropriate for calculating the signature
# of a command line...if this changes, we should rebuild.
SUBST_CMD = 0
SUBST_RAW = 1
SUBST_SIG = 2
_rm = re.compile(r'\$[()]')
# Note the pattern below only matches $( or $) when there is no
# preceeding $. (Thus the (?<!\$))
_rm_split = re.compile(r'(?<!\$)(\$[()])')
# Indexed by the SUBST_* constants above.
_regex_remove = [ _rm, None, _rm_split ]
[docs]
def _rm_list(list):
return [l for l in list if l not in ('$(', '$)')]
[docs]
def _remove_list(list):
result = []
depth = 0
for l in list:
if l == '$(':
depth += 1
elif l == '$)':
depth -= 1
if depth < 0:
break
elif depth == 0:
result.append(l)
if depth != 0:
return None
return result
# Indexed by the SUBST_* constants above.
_list_remove = [ _rm_list, None, _remove_list ]
# Regular expressions for splitting strings and handling substitutions,
# for use by the scons_subst() and scons_subst_list() functions:
#
# The first expression compiled matches all of the $-introduced tokens
# that we need to process in some way, and is used for substitutions.
# The expressions it matches are:
#
# "$$"
# "$("
# "$)"
# "$variable" [must begin with alphabetic or underscore]
# "${any stuff}"
#
# The second expression compiled is used for splitting strings into tokens
# to be processed, and it matches all of the tokens listed above, plus
# the following that affect how arguments do or don't get joined together:
#
# " " [white space]
# "non-white-space" [without any dollar signs]
# "$" [single dollar sign]
#
_dollar_exps_str = r'\$[\$\(\)]|\$[_a-zA-Z][\.\w]*|\${[^}]*}'
_dollar_exps = re.compile(r'(%s)' % _dollar_exps_str)
_separate_args = re.compile(r'(%s|\s+|[^\s$]+|\$)' % _dollar_exps_str)
# This regular expression is used to replace strings of multiple white
# space characters in the string result from the scons_subst() function.
_space_sep = re.compile(r'[\t ]+(?![^{]*})')
[docs]
def scons_subst(strSubst, env, mode=SUBST_RAW, target=None, source=None, gvars={}, lvars={}, conv=None, overrides: Optional[dict] = None):
"""Expand a string or list containing construction variable
substitutions.
This is the work-horse function for substitutions in file names
and the like. The companion scons_subst_list() function (below)
handles separating command lines into lists of arguments, so see
that function if that's what you're looking for.
"""
if (isinstance(strSubst, str) and '$' not in strSubst) or isinstance(strSubst, CmdStringHolder):
return strSubst
if conv is None:
conv = _strconv[mode]
# Doing this every time is a bit of a waste, since the Executor
# has typically already populated the OverrideEnvironment with
# $TARGET/$SOURCE variables. We're keeping this (for now), though,
# because it supports existing behavior that allows us to call
# an Action directly with an arbitrary target+source pair, which
# we use in Tool/tex.py to handle calling $BIBTEX when necessary.
# If we dropped that behavior (or found another way to cover it),
# we could get rid of this call completely and just rely on the
# Executor setting the variables.
if 'TARGET' not in lvars:
d = subst_dict(target, source)
if d:
lvars = lvars.copy()
lvars.update(d)
# Allow last ditch chance to override lvars
if overrides:
lvars.update(overrides)
# We're (most likely) going to eval() things. If Python doesn't
# find a __builtins__ value in the global dictionary used for eval(),
# it copies the current global values for you. Avoid this by
# setting it explicitly and then deleting, so we don't pollute the
# construction environment Dictionary(ies) that are typically used
# for expansion.
gvars['__builtins__'] = __builtins__
ss = StringSubber(env, mode, conv, gvars)
result = ss.substitute(strSubst, lvars)
try:
del gvars['__builtins__']
except KeyError:
pass
res = result
if is_String(result):
# Remove $(-$) pairs and any stuff in between,
# if that's appropriate.
remove = _regex_remove[mode]
if remove:
if mode == SUBST_SIG:
result = _list_remove[mode](remove.split(result))
if result is None:
raise SCons.Errors.UserError("Unbalanced $(/$) in: " + res)
result = ' '.join(result)
else:
result = remove.sub('', result)
if mode != SUBST_RAW:
# Compress strings of white space characters into
# a single space.
result = _space_sep.sub(' ', result).strip()
# Now replace escaped $'s currently "$$"
# This is needed because we now retain $$ instead of
# replacing them during substition to avoid
# improperly trying to escape "$$(" as being "$("
result = result.replace('$$','$')
elif is_Sequence(result):
remove = _list_remove[mode]
if remove:
result = remove(result)
if result is None:
raise SCons.Errors.UserError("Unbalanced $(/$) in: " + str(res))
return result
[docs]
def scons_subst_list(strSubst, env, mode=SUBST_RAW, target=None, source=None, gvars={}, lvars={}, conv=None, overrides: Optional[dict] = None):
"""Substitute construction variables in a string (or list or other
object) and separate the arguments into a command list.
The companion scons_subst() function (above) handles basic
substitutions within strings, so see that function instead
if that's what you're looking for.
"""
if conv is None:
conv = _strconv[mode]
# Doing this every time is a bit of a waste, since the Executor
# has typically already populated the OverrideEnvironment with
# $TARGET/$SOURCE variables. We're keeping this (for now), though,
# because it supports existing behavior that allows us to call
# an Action directly with an arbitrary target+source pair, which
# we use in Tool/tex.py to handle calling $BIBTEX when necessary.
# If we dropped that behavior (or found another way to cover it),
# we could get rid of this call completely and just rely on the
# Executor setting the variables.
if 'TARGET' not in lvars:
d = subst_dict(target, source)
if d:
lvars = lvars.copy()
lvars.update(d)
# Allow caller to specify last ditch override of lvars
if overrides:
lvars.update(overrides)
# We're (most likely) going to eval() things. If Python doesn't
# find a __builtins__ value in the global dictionary used for eval(),
# it copies the current global values for you. Avoid this by
# setting it explicitly and then deleting, so we don't pollute the
# construction environment Dictionary(ies) that are typically used
# for expansion.
gvars['__builtins__'] = __builtins__
ls = ListSubber(env, mode, conv, gvars)
ls.substitute(strSubst, lvars, 0)
try:
del gvars['__builtins__']
except KeyError:
pass
return ls.data
[docs]
def scons_subst_once(strSubst, env, key):
"""Perform single (non-recursive) substitution of a single
construction variable keyword.
This is used when setting a variable when copying or overriding values
in an Environment. We want to capture (expand) the old value before
we override it, so people can do things like:
env2 = env.Clone(CCFLAGS = '$CCFLAGS -g')
We do this with some straightforward, brute-force code here...
"""
if isinstance(strSubst, str) and strSubst.find('$') < 0:
return strSubst
matchlist = ['$' + key, '${' + key + '}']
val = env.get(key, '')
def sub_match(match, val=val, matchlist=matchlist):
a = match.group(1)
if a in matchlist:
a = val
if is_Sequence(a):
return ' '.join(map(str, a))
else:
return str(a)
if is_Sequence(strSubst):
result = []
for arg in strSubst:
if is_String(arg):
if arg in matchlist:
arg = val
if is_Sequence(arg):
result.extend(arg)
else:
result.append(arg)
else:
result.append(_dollar_exps.sub(sub_match, arg))
else:
result.append(arg)
return result
elif is_String(strSubst):
return _dollar_exps.sub(sub_match, strSubst)
else:
return strSubst
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