"Merge pull request #472 from marcellarius/fix-glob-ordering\n\nSort …

…filenames when globbing"

src/webassets/env.py

@@ -109,14 +109,19 @@ class Resolver(object):
     """
 
     def glob(self, basedir, expr):
-        """Generator that runs when a glob expression needs to be
-        resolved. Yields a list of absolute filenames.
+        """Evaluates a glob expression.
+         Yields a sorted list of absolute filenames.
         """
-        expr = path.join(basedir, expr)
-        for filename in glob.iglob(expr):
-            if path.isdir(filename):
-                continue
-            yield filename
+        def glob_generator(basedir, expr):
+            expr = path.join(basedir, expr)
+            for filename in glob.iglob(expr):
+                if path.isdir(filename):
+                    continue
+                yield path.normpath(filename)
+
+        # The order of files returned by the glob implementation is undefined,
+        # so sort alphabetically to maintain a deterministic ordering
+        return sorted(glob_generator(basedir, expr))
 
     def consider_single_directory(self, directory, item):
         """Searches for ``item`` within ``directory``. Is able to
@@ -128,7 +133,7 @@ def consider_single_directory(self, directory, item):
         expr = path.join(directory, item)
         if has_magic(expr):
             # Note: No error if glob returns an empty list
-            return list(self.glob(directory, item))
+            return self.glob(directory, item)
         else:
             if path.exists(expr):
                 return expr
@@ -151,14 +156,14 @@ def search_load_path(self, ctx, item):
             # We glob all paths.
             result = []
             for path in ctx.load_path:
-                result.extend(list(self.glob(path, item)))
+                result.extend(self.glob(path, item))
             return result
         else:
             # Single file, stop when we find the first match, or error
             # out otherwise. We still use glob() because then the load_path
             # itself can contain globs. Neat!
             for path in ctx.load_path:
-                result = list(self.glob(path, item))
+                result = self.glob(path, item)
                 if result:
                     return result
             raise IOError("'%s' not found in load path: %s" % (

tests/test_bundle_various.py

@@ -7,6 +7,7 @@
 
 import copy
 from os import path
+import uuid
 try:
     from urllib.request import \
         HTTPHandler, build_opener, install_opener, addinfourl
@@ -526,12 +527,26 @@ def test_do_not_glob_directories(self):
                            get_all_bundle_files(self.mkbundle('*'))))
 
     def test_glob_exclude_output(self):
-        """Never include the output file in the globbinb result.
+        """Never include the output file in the globbing result.
         """
         self.create_files(['out.js'])
         assert not list(filter(lambda s: 'out.js' in s,
             get_all_bundle_files(self.mkbundle('*', output='out.js'))))
 
+    def test_glob_ordering_consistent(self):
+        """Glob results should be sorted alphabetically
+        """
+        # Create randomly named files using a UUID for both name and contents.
+        unique_names = [uuid.uuid4().hex for i in range(10)]
+        files = {}
+        for name in unique_names:
+            files[name + ".uuid"] = name
+        self.create_files(files)
+        self.mkbundle("*.uuid", output="out").build()
+        content = self.get("out").split("\n")
+        expected_output = sorted(unique_names)
+        assert content == expected_output
+
 
 class MockHTTPHandler(HTTPHandler):