msvcdeps: Faster case correction

Visual Studio returns paths to dependencies with incorrect case.
ant_glob() is very slow for this use case (40~50% impact to overall
build time). This patch uses os.listdir() to find the correct case
of each path component.

waflib/extras/msvcdeps.py

@@ -50,23 +50,42 @@ def apply_msvcdeps_flags(taskgen):
 		if taskgen.env.get_flat(flag).find(PREPROCESSOR_FLAG) < 0:
 			taskgen.env.append_value(flag, PREPROCESSOR_FLAG)
 
+
+def get_correct_path_case(base_path, path):
+	'''
+	Return a case-corrected version of ``path`` by searching the filesystem for
+	``path``, relative to ``base_path``, using the case returned by the filesystem.
+	'''
+	components = Utils.split_path(path)
+
+	corrected_path = ''
+	if os.path.isabs(path):
+		corrected_path = components.pop(0).upper() + os.sep
+
+	for part in components:
+		part = part.lower()
+		search_path = os.path.join(base_path, corrected_path)
+		for item in os.listdir(search_path):
+			if item.lower() == part:
+				corrected_path = os.path.join(corrected_path, item)
+				break
+		else:
+			raise ValueError("Can't find %r in %r" % (part, search_path))
+
+	return corrected_path
+
+
 def path_to_node(base_node, path, cached_nodes):
 	'''
 	Take the base node and the path and return a node
 	Results are cached because searching the node tree is expensive
 	The following code is executed by threads, it is not safe, so a lock is needed...
 	'''
-	# normalize the path because ant_glob() does not understand
-	# parent path components (..)
+	# normalize the path to remove parent path components (..)
 	path = os.path.normpath(path)
 
 	# normalize the path case to increase likelihood of a cache hit
-	path = os.path.normcase(path)
-
-	# ant_glob interprets [] and () characters, so those must be replaced
-	path = path.replace('[', '?').replace(']', '?').replace('(', '[(]').replace(')', '[)]')
-
-	node_lookup_key = (base_node, path)
+	node_lookup_key = (base_node, os.path.normcase(path))
 
 	try:
 		node = cached_nodes[node_lookup_key]
@@ -76,8 +95,8 @@ def path_to_node(base_node, path, cached_nodes):
 			try:
 				node = cached_nodes[node_lookup_key]
 			except KeyError:
-				node_list = base_node.ant_glob([path], ignorecase=True, remove=False, quiet=True, regex=False)
-				node = cached_nodes[node_lookup_key] = node_list[0] if node_list else None
+				path = get_correct_path_case(base_node.abspath(), path)
+				node = cached_nodes[node_lookup_key] = base_node.find_node(path)
 
 	return node