1 files changed, 48 insertions, 6 deletions

diff --git a/coverage/files.py b/coverage/files.py
index 632d6e31..40af7bf7 100644
--- a/coverage/files.py
+++ b/coverage/files.py
@@ -2,14 +2,14 @@
 
 from coverage.backward import to_string
 from coverage.misc import CoverageException
-import fnmatch, os, re, sys
+import fnmatch, os, os.path, re, sys
 
 class FileLocator(object):
     """Understand how filenames work."""
 
     def __init__(self):
         # The absolute path to our current directory.
-        self.relative_dir = abs_file(os.curdir) + os.sep
+        self.relative_dir = os.path.normcase(abs_file(os.curdir) + os.sep)
 
         # Cache of results of calling the canonical_filename() method, to
         # avoid duplicating work.
@@ -22,8 +22,9 @@ class FileLocator(object):
         `FileLocator` was constructed.
 
         """
-        if filename.startswith(self.relative_dir):
-            filename = filename.replace(self.relative_dir, "", 1)
+        fnorm = os.path.normcase(filename)
+        if fnorm.startswith(self.relative_dir):
+            filename = filename[len(self.relative_dir):]
         return filename
 
     def canonical_filename(self, filename):
@@ -74,9 +75,50 @@ class FileLocator(object):
         return None
 
 
+if sys.platform == 'win32':
+
+    def actual_path(path):
+        """Get the actual path of `path`, including the correct case."""
+        if path in actual_path.cache:
+            return actual_path.cache[path]
+
+        head, tail = os.path.split(path)
+        if not tail:
+            actpath = head
+        elif not head:
+            actpath = tail
+        else:
+            head = actual_path(head)
+            if head in actual_path.list_cache:
+                files = actual_path.list_cache[head]
+            else:
+                try:
+                    files = os.listdir(head)
+                except OSError:
+                    files = []
+                actual_path.list_cache[head] = files
+            normtail = os.path.normcase(tail)
+            for f in files:
+                if os.path.normcase(f) == normtail:
+                    tail = f
+                    break
+            actpath = os.path.join(head, tail)
+        actual_path.cache[path] = actpath
+        return actpath
+
+    actual_path.cache = {}
+    actual_path.list_cache = {}
+
+else:
+    def actual_path(filename):
+        """The actual path for non-Windows platforms."""
+        return filename
+
 def abs_file(filename):
     """Return the absolute normalized form of `filename`."""
-    return os.path.normcase(os.path.abspath(os.path.realpath(filename)))
+    path = os.path.abspath(os.path.realpath(filename))
+    path = actual_path(path)
+    return path
 
 
 def prep_patterns(patterns):
@@ -196,7 +238,7 @@ class PathAliases(object):
         # either separator.
         regex_pat = regex_pat.replace(r"\/", r"[\\/]")
         # We want case-insensitive matching, so add that flag.
-        regex = re.compile("(?i)" + regex_pat)
+        regex = re.compile(r"(?i)" + regex_pat)
 
         # Normalize the result: it must end with a path separator.
         result_sep = sep(result)