Correct the order in which OutputDirectory and IntermediateDirectory are defined.

pylib/gyp/xcode_emulation.py

Index: pylib/gyp/xcode_emulation.py
===================================================================
--- pylib/gyp/xcode_emulation.py	(revision 1364)
+++ pylib/gyp/xcode_emulation.py	(working copy)
@@ -979,6 +979,7 @@
   """Takes a dict |env| whose values are strings that can refer to other keys,
   for example env['foo'] = '$(bar) and $(baz)'. Returns a list L of all keys of
   env such that key2 is after key1 in L if env[key2] refers to env[key1].
+  (This is really reversed topological order).

[Nico, 2012/05/10 19:20:23]

Remove useless comment addition

[bradn, 2012/05/10 20:17:56]

Yeah the double reversing thing seems goofy.
I had been wary of changing return values of these functions (as there are some
other callers), but consistency would be good.
Changing..

 
   Throws an Exception in case of dependency cycles.
   """
@@ -986,62 +987,22 @@
   # order is important. Below is the logic to compute the dependency graph
   # and sort it.
   regex = re.compile(r'\$\{([a-zA-Z0-9\-_]+)\}')
-
-  # First sort the list of keys.
-  key_list = sorted(env.keys())
-
-  # Phase 1: Create a set of edges of (DEPENDEE, DEPENDER) where in the graph,
-  # DEPENDEE -> DEPENDER. Also create sets of dependers and dependees.
-  edges = set()
-  dependees = set()
-  dependers = set()
-  for k in key_list:
-    matches = regex.findall(env[k])
-    if not len(matches):
-      continue
-
-    depends_on_other_var = False
+  def GetEdges(node):
+    # Get all variable references for variable defined in env.
+    matches = set([v for v in regex.findall(env[node]) if v in env])
     for dependee in matches:
       assert '${' not in dependee, 'Nested variables not supported: ' + dependee
-      if dependee in env:
-        edges.add((dependee, k))
-        dependees.add(dependee)
-        depends_on_other_var = True
-    if depends_on_other_var:
-      dependers.add(k)
+    return matches
 
-  # Phase 2: Create a list of graph nodes with no incoming edges.
-  sorted_nodes = []
-  edgeless_nodes = dependees - dependers
+  try:
+    order = gyp.common.TopologicallySorted(env.keys(), GetEdges)
+    order.reverse()

[Nico, 2012/05/10 19:20:23]

Err g.c.TS also reverses last thing. Maybe it shouldn't do that then?

[bradn, 2012/05/10 20:17:56]

Yeah, I think I'll just move to forward topological order everywhere.

+    return order
+  except CycleError, e:
+    raise Exception(
+        'Xcode environment variables are cyclically dependent: ' + str(e.nodes))
 
-  # Phase 3: Perform Kahn topological sort.
-  while len(edgeless_nodes):
-    # Find a node with no incoming edges, add it to the sorted list, and
-    # remove it from the list of nodes that aren't part of the graph.
-    node = edgeless_nodes.pop()
-    sorted_nodes.append(node)
-    key_list.remove(node)
 
-    # Find all the edges between |node| and other nodes.
-    edges_to_node = [e for e in edges if e[0] == node]
-    for edge in edges_to_node:
-      edges.remove(edge)
-      # If the node connected to |node| by |edge| has no other incoming edges,
-      # add it to |edgeless_nodes|.
-      if not len([e for e in edges if e[1] == edge[1]]):
-        edgeless_nodes.add(edge[1])
-
-  # Any remaining edges indicate a cycle.
-  if len(edges):
-    raise Exception('Xcode environment variables are cyclically dependent: ' +
-        str(edges))
-
-  # Append the "nodes" not in the graph to those that were just sorted.
-  sorted_nodes.extend(key_list)
-
-  return sorted_nodes
-
-
 def GetSpecPostbuildCommands(spec, quiet=False):
   """Returns the list of postbuilds explicitly defined on |spec|, in a form
   executable by a shell."""