Added an unmodified copy of SCons to third_party.

scons-2.0.1/engine/SCons/Variables/__init__.py

+"""engine.SCons.Variables
+
+This file defines the Variables class that is used to add user-friendly
+customizable variables to an SCons build.
+"""
+
+#
+# Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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.
+
+__revision__ = "src/engine/SCons/Variables/__init__.py 5134 2010/08/16 23:02:40 bdeegan"
+
+import os.path
+import sys
+
+import SCons.Environment
+import SCons.Errors
+import SCons.Util
+import SCons.Warnings
+
+from BoolVariable import BoolVariable  # okay
+from EnumVariable import EnumVariable  # okay
+from ListVariable import ListVariable  # naja
+from PackageVariable import PackageVariable # naja
+from PathVariable import PathVariable # okay
+
+
+class Variables(object):
+    instance=None
+
+    """
+    Holds all the options, updates the environment with the variables,
+    and renders the help text.
+    """
+    def __init__(self, files=[], args={}, is_global=1):
+        """
+        files - [optional] List of option configuration files to load
+            (backward compatibility) If a single string is passed it is
+                                     automatically placed in a file list
+        """
+        self.options = []
+        self.args = args
+        if not SCons.Util.is_List(files):
+            if files:
+                files = [ files ]
+            else:
+                files = []
+        self.files = files
+        self.unknown = {}
+
+        # create the singleton instance
+        if is_global:
+            self=Variables.instance
+
+            if not Variables.instance:
+                Variables.instance=self
+
+    def _do_add(self, key, help="", default=None, validator=None, converter=None):
+        class Variable(object):
+            pass
+
+        option = Variable()
+
+        # if we get a list or a tuple, we take the first element as the
+        # option key and store the remaining in aliases.
+        if SCons.Util.is_List(key) or SCons.Util.is_Tuple(key):
+            option.key     = key[0]
+            option.aliases = key[1:]
+        else:
+            option.key     = key
+            option.aliases = [ key ]
+        option.help = help
+        option.default = default
+        option.validator = validator
+        option.converter = converter
+
+        self.options.append(option)
+        
+        # options might be added after the 'unknown' dict has been set up,
+        # so we remove the key and all its aliases from that dict
+        for alias in list(option.aliases) + [ option.key ]:
+            if alias in self.unknown:
+                del self.unknown[alias]
+
+    def keys(self):
+        """
+        Returns the keywords for the options
+        """
+        return [o.key for o in self.options]
+
+    def Add(self, key, help="", default=None, validator=None, converter=None, **kw):
+        """
+        Add an option.
+
+        key - the name of the variable, or a list or tuple of arguments
+        help - optional help text for the options
+        default - optional default value
+        validator - optional function that is called to validate the option's value
+                    Called with (key, value, environment)
+        converter - optional function that is called to convert the option's value before
+                    putting it in the environment.
+        """
+
+        if SCons.Util.is_List(key) or isinstance(key, tuple):
+            self._do_add(*key)
+            return
+
+        if not SCons.Util.is_String(key) or \
+            not SCons.Environment.is_valid_construction_var(key):
+                raise SCons.Errors.UserError("Illegal Variables.Add() key `%s'" % str(key))
+
+        self._do_add(key, help, default, validator, converter)
+
+    def AddVariables(self, *optlist):
+        """
+        Add a list of options.
+
+        Each list element is a tuple/list of arguments to be passed on
+        to the underlying method for adding options.
+
+        Example:
+          opt.AddVariables(
+            ('debug', '', 0),
+            ('CC', 'The C compiler'),
+            ('VALIDATE', 'An option for testing validation', 'notset',
+             validator, None),
+            )
+        """
+        for o in optlist:
+            self._do_add(*o)
+
+
+    def Update(self, env, args=None):
+        """
+        Update an environment with the option variables.
+
+        env - the environment to update.
+        """
+
+        values = {}
+
+        # first set the defaults:
+        for option in self.options:
+            if not option.default is None:
+                values[option.key] = option.default
+
+        # next set the value specified in the options file
+        for filename in self.files:
+            if os.path.exists(filename):
+                dir = os.path.split(os.path.abspath(filename))[0]
+                if dir:
+                    sys.path.insert(0, dir)
+                try:
+                    values['__name__'] = filename
+                    exec open(filename, 'rU').read() in {}, values
+                finally:
+                    if dir:
+                        del sys.path[0]
+                    del values['__name__']
+
+        # set the values specified on the command line
+        if args is None:
+            args = self.args
+
+        for arg, value in args.items():
+            added = False
+            for option in self.options:
+                if arg in list(option.aliases) + [ option.key ]:
+                    values[option.key] = value
+                    added = True
+            if not added:
+                self.unknown[arg] = value
+
+        # put the variables in the environment:
+        # (don't copy over variables that are not declared as options)
+        for option in self.options:
+            try:
+                env[option.key] = values[option.key]
+            except KeyError:
+                pass
+
+        # Call the convert functions:
+        for option in self.options:
+            if option.converter and option.key in values:
+                value = env.subst('${%s}'%option.key)
+                try:
+                    try:
+                        env[option.key] = option.converter(value)
+                    except TypeError:
+                        env[option.key] = option.converter(value, env)
+                except ValueError, x:
+                    raise SCons.Errors.UserError('Error converting option: %s\n%s'%(option.key, x))
+
+
+        # Finally validate the values:
+        for option in self.options:
+            if option.validator and option.key in values:
+                option.validator(option.key, env.subst('${%s}'%option.key), env)
+
+    def UnknownVariables(self):
+        """
+        Returns any options in the specified arguments lists that
+        were not known, declared options in this object.
+        """
+        return self.unknown
+
+    def Save(self, filename, env):
+        """
+        Saves all the options in the given file.  This file can
+        then be used to load the options next run.  This can be used
+        to create an option cache file.
+
+        filename - Name of the file to save into
+        env - the environment get the option values from
+        """
+
+        # Create the file and write out the header
+        try:
+            fh = open(filename, 'w')
+
+            try:
+                # Make an assignment in the file for each option
+                # within the environment that was assigned a value
+                # other than the default.
+                for option in self.options:
+                    try:
+                        value = env[option.key]
+                        try:
+                            prepare = value.prepare_to_store
+                        except AttributeError:
+                            try:
+                                eval(repr(value))
+                            except KeyboardInterrupt:
+                                raise
+                            except:
+                                # Convert stuff that has a repr() that
+                                # cannot be evaluated into a string
+                                value = SCons.Util.to_String(value)
+                        else:
+                            value = prepare()
+
+                        defaultVal = env.subst(SCons.Util.to_String(option.default))
+                        if option.converter:
+                            defaultVal = option.converter(defaultVal)
+
+                        if str(env.subst('${%s}' % option.key)) != str(defaultVal):
+                            fh.write('%s = %s\n' % (option.key, repr(value)))
+                    except KeyError:
+                        pass
+            finally:
+                fh.close()
+
+        except IOError, x:
+            raise SCons.Errors.UserError('Error writing options to file: %s\n%s' % (filename, x))
+
+    def GenerateHelpText(self, env, sort=None):
+        """
+        Generate the help text for the options.
+
+        env - an environment that is used to get the current values
+              of the options.
+        """
+
+        if sort:
+            options = sorted(self.options, key=lambda x: x.key)
+        else:
+            options = self.options
+
+        def format(opt, self=self, env=env):
+            if opt.key in env:
+                actual = env.subst('${%s}' % opt.key)
+            else:
+                actual = None
+            return self.FormatVariableHelpText(env, opt.key, opt.help, opt.default, actual, opt.aliases)
+        lines = [_f for _f in map(format, options) if _f]
+
+        return ''.join(lines)
+
+    format  = '\n%s: %s\n    default: %s\n    actual: %s\n'
+    format_ = '\n%s: %s\n    default: %s\n    actual: %s\n    aliases: %s\n'
+
+    def FormatVariableHelpText(self, env, key, help, default, actual, aliases=[]):
+        # Don't display the key name itself as an alias.
+        aliases = [a for a in aliases if a != key]
+        if len(aliases)==0:
+            return self.format % (key, help, default, actual)
+        else:
+            return self.format_ % (key, help, default, actual, aliases)
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4: