3 files changed, 45 insertions, 3 deletions
diff --git a/mammoth/docx/__init__.py b/mammoth/docx/__init__.py
index a71ca0c..2bee161 100644
--- a/mammoth/docx/__init__.py
+++ b/mammoth/docx/__init__.py
@@ -1,7 +1,7 @@
 from functools import partial
 import os
 
-from .. import results, lists
+from .. import results, lists, zips
 from .document_xml import read_document_xml_element
 from .content_types_xml import empty_content_types, read_content_types_xml_element
 from .relationships_xml import read_relationships_xml_element, Relationships
@@ -125,8 +125,8 @@ def _part_with_body_reader(document_path, zip_file):
 
 
 def _find_relationships_path_for(name):
-    parts = name.split("/")
-    return "/".join(parts[:-1] + ["_rels/" + parts[-1] + ".rels"])
+    dirname, basename = zips.split_path(name)
+    return zips.join_path(dirname, "_rels", basename + ".rels")
     
 
 def _read_relationships(zip_file, name):
diff --git a/mammoth/zips.py b/mammoth/zips.py
index 432be5d..cca0b49 100644
--- a/mammoth/zips.py
+++ b/mammoth/zips.py
@@ -54,3 +54,15 @@ def update_zip(fileobj, files):
     fileobj.seek(0)
     destination_fileobj.seek(0)
     shutil.copyfileobj(destination_fileobj, fileobj)
+
+
+def split_path(path):
+    parts = path.rsplit("/", 1)
+    if len(parts) == 1:
+        return ("", path)
+    else:
+        return tuple(parts)
+
+
+def join_path(*args):
+    return "/".join(list(filter(None, args)))
diff --git a/tests/zips_tests.py b/tests/zips_tests.py
new file mode 100644
index 0000000..671b5cb
--- /dev/null
+++ b/tests/zips_tests.py
@@ -0,0 +1,30 @@
+from nose.tools import istest, assert_equal
+
+from mammoth import zips
+
+
+@istest
+def split_path_splits_zip_paths_on_last_forward_slash():
+    assert_equal(("a", "b"), zips.split_path("a/b"))
+    assert_equal(("a/b", "c"), zips.split_path("a/b/c"))
+    assert_equal(("/a/b", "c"), zips.split_path("/a/b/c"))
+
+
+@istest
+def when_path_has_no_forward_slashes_then_split_path_returns_empty_dirname():
+    assert_equal(("", "name"), zips.split_path("name"))
+
+
+@istest
+def join_path_joins_arguments_with_forward_slashes():
+    assert_equal("a/b", zips.join_path("a", "b"))
+    assert_equal("a/b/c", zips.join_path("a/b", "c"))
+    assert_equal("/a/b/c", zips.join_path("/a/b", "c"))
+
+
+@istest
+def empty_parts_are_ignored_when_joining_paths():
+    assert_equal("a", zips.join_path("", "a"))
+    assert_equal("b", zips.join_path("", "b"))
+    assert_equal("a/b", zips.join_path("a", "", "b"))
+