From cdd68fba46bb94e627c78ae0f220c59db7f2a889 Mon Sep 17 00:00:00 2001
From: stevenknight <stevenknight@fdb21ef1-2011-0410-befe-b5e4ea1792b1>
Date: Wed, 26 Sep 2001 13:46:18 +0000
Subject: [PATCH] Change the env.Dictionary to an access method for an
 env._dict attribute.

git-svn-id: http://scons.tigris.org/svn/scons/trunk@70 fdb21ef1-2011-0410-befe-b5e4ea1792b1
---
 doc/design/engine.sgml               |  9 ---------
 src/engine/SCons/Environment.py      | 18 +++++++++++++-----
 src/engine/SCons/EnvironmentTests.py | 18 +++++++++++-------
 3 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/doc/design/engine.sgml b/doc/design/engine.sgml
index 3bb636b0..92343bf3 100644
--- a/doc/design/engine.sgml
+++ b/doc/design/engine.sgml
@@ -152,15 +152,6 @@
 	dict = env.Dictionary()
 	</programlisting>
 
-<REMARK>
-In the current source code, I implemented this as a dictionary attribute
-named <literal>Dictionary</literal>.  While reasonably Pythonic, this
-is ultimately Not Good.  We don't want people using a reference to the
-dictionary to change construction variables out from under an existing
-environment.  We should use an internal <literal>_dict</literal>
-attribute and control access to it through a method, as specified above.
-</REMARK>
-
   <para>
 
    If any arguments are supplied, then just the corresponding value(s)
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index 5561cced..508392ba 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -53,7 +53,7 @@ class Environment:
     """
 
     def __init__(self, **kw):
-	self.Dictionary = {}
+	self._dict = {}
 	if kw.has_key('BUILDERS'):
 	    builders = kw['BUILDERS']
 	    if not type(builders) is types.ListType:
@@ -61,7 +61,7 @@ class Environment:
 	else:
 	    import SCons.Defaults
 	    kw['BUILDERS'] = SCons.Defaults.Builders[:]
-	self.Dictionary.update(copy.deepcopy(kw))
+	self._dict.update(copy.deepcopy(kw))
 
 	class BuilderWrapper:
 	    """Wrapper class that allows an environment to
@@ -83,7 +83,7 @@ class Environment:
 
 
     def __cmp__(self, other):
-	return cmp(self.Dictionary, other.Dictionary)
+	return cmp(self._dict, other._dict)
 
     def Builders(self):
 	pass	# XXX
@@ -107,7 +107,7 @@ class Environment:
 	"""Update an existing construction Environment with new
 	construction variables and/or values.
 	"""
-	self.Dictionary.update(copy.deepcopy(kw))
+	self._dict.update(copy.deepcopy(kw))
 
     def	Depends(self, target, dependency):
 	"""Explicity specify that 'target's depend on 'dependency'."""
@@ -120,6 +120,14 @@ class Environment:
 	    tlist = tlist[0]
 	return tlist
 
+    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 subst(self, string):
 	"""Recursively interpolates construction variables from the
 	Environment into the specified string, returning the expanded
@@ -134,7 +142,7 @@ class Environment:
 	    key = m.group(1)
 	    if key[:1] == '{' and key[-1:] == '}':
 		key = key[1:-1]
-	    if _self.Dictionary.has_key(key): return _self.Dictionary[key]
+	    if _self._dict.has_key(key): return _self._dict[key]
 	    else: return ''
 	n = 1
 	while n != 0:
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index 149ba748..04881731 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -75,9 +75,9 @@ class EnvironmentTestCase(unittest.TestCase):
 	assert env1 == env1copy
 
 	env3 = env1.Copy(XXX = 'x3', ZZZ = 'z3')
-	assert env3.Dictionary['XXX'] == 'x3'
-	assert env3.Dictionary['YYY'] == 'y'
-	assert env3.Dictionary['ZZZ'] == 'z3'
+	assert env3.Dictionary('XXX') == 'x3'
+	assert env3.Dictionary('YYY') == 'y'
+	assert env3.Dictionary('ZZZ') == 'z3'
 	assert env1 == env1copy
 
     def test_Dictionary(self):
@@ -86,10 +86,14 @@ class EnvironmentTestCase(unittest.TestCase):
 	Fetch them from the Dictionary and check for well-known
 	defaults that get inserted.
 	"""
-	env = Environment(XXX = 'x', YYY = 'y')
-	assert env.Dictionary['XXX'] == 'x'
-	assert env.Dictionary['YYY'] == 'y'
-	assert env.Dictionary.has_key('BUILDERS')
+	env = Environment(XXX = 'x', YYY = 'y', ZZZ = 'z')
+	assert env.Dictionary('XXX') == 'x'
+	assert env.Dictionary('YYY') == 'y'
+	assert env.Dictionary('XXX', 'ZZZ') == ['x', 'z']
+	xxx, zzz = env.Dictionary('XXX', 'ZZZ')
+	assert xxx == 'x'
+	assert zzz == 'z'
+	assert env.Dictionary().has_key('BUILDERS')
 
     def test_Environment(self):
 	"""Test construction Environments creation
-- 
2.26.2