Issue 1086: add support for generic batch build actions, and

specific support for batched compilation for Microsoft Visual C/C++.

Merged revisions 3819-3851,3854-3869,3871-3877,3880 via svnmerge from
http://scons.tigris.org/svn/scons/branches/sgk_batch

........
  r3820 | stevenknight | 2008-12-09 23:59:14 -0800 (Tue, 09 Dec 2008) | 6 lines

  Issue 1086:  Batch compilation support:
  * $MSVC_BATCH to control Visual C/C++ batch compilation.
  * New $CHANGED_SOURCES, $CHANGED_TARGETS, $UNCHANGED_SOURCES and
    $UNCHANGED_TARGETS construction variables.
  * New Action(batch_key=, targets=) keyword arguments.
........
  r3880 | stevenknight | 2009-01-07 20:50:41 -0800 (Wed, 07 Jan 2009) | 3 lines

  Use UniqueList objects to collect the all_children(), all_prerequisites()
  and all_sources() lists instead of calling uniquer_hashables() by hand.
........

1 files changed, 30 insertions, 17 deletions

diff --git a/src/engine/SCons/Util.py b/src/engine/SCons/Util.py
index cbec5dd..a9f7b70 100644
--- a/src/engine/SCons/Util.py
+++ b/src/engine/SCons/Util.py
@@ -1092,11 +1092,12 @@ class Selector(OrderedDict):
     """A callable ordered dictionary that maps file suffixes to
     dictionary values.  We preserve the order in which items are added
     so that get_suffix() calls always return the first suffix added."""
-    def __call__(self, env, source):
-        try:
-            ext = source[0].suffix
-        except IndexError:
-            ext = ""
+    def __call__(self, env, source, ext=None):
+        if ext is None:
+            try:
+                ext = source[0].suffix
+            except IndexError:
+                ext = ""
         try:
             return self[ext]
         except KeyError:
@@ -1561,20 +1562,32 @@ class Null:
             #cls._inst = type.__new__(cls, *args, **kwargs)
             cls._inst = apply(type.__new__, (cls,) + args, kwargs)
         return cls._inst
-    def __init__(self, *args, **kwargs): pass
-    def __call__(self, *args, **kwargs): return self
-    def __repr__(self): return "Null(0x%08X)" % id(self)
-    def __nonzero__(self): return False
-    def __getattr__(self, mname): return self
-    def __setattr__(self, name, value): return self
-    def __delattr__(self, name): return self
+    def __init__(self, *args, **kwargs):
+        pass
+    def __call__(self, *args, **kwargs):
+        return self
+    def __repr__(self):
+        return "Null(0x%08X)" % id(self)
+    def __nonzero__(self):
+        return False
+    def __getattr__(self, name):
+        return self
+    def __setattr__(self, name, value):
+        return self
+    def __delattr__(self, name):
+        return self
 
 class NullSeq(Null):
-  def __len__(self): return 0
-  def __iter__(self): return iter(())
-  def __getitem__(self, i): return self
-  def __delitem__(self, i): return self
-  def __setitem__(self, i, v): return self
+    def __len__(self):
+        return 0
+    def __iter__(self):
+        return iter(())
+    def __getitem__(self, i):
+        return self
+    def __delitem__(self, i):
+        return self
+    def __setitem__(self, i, v):
+        return self
 
 
 del __revision__