diff --git a/papers/papers b/papers/papers
index eeed970..1cc68db 100755
--- a/papers/papers
+++ b/papers/papers
@@ -1,5 +1,5 @@
 #!/usr/bin/env python2
 # -*- coding:utf-8 -*-
 
-import papers_cmd
+from papers import papers_cmd
 papers_cmd.execute()
\ No newline at end of file
diff --git a/papers/papers_cmd.py b/papers/papers_cmd.py
index 210b3cc..eb59bff 100644
--- a/papers/papers_cmd.py
+++ b/papers/papers_cmd.py
@@ -26,24 +26,25 @@ cmds = collections.OrderedDict([
         ('update',      commands.update_cmd),
         ])
 
-config = configs.read_config()
-ui = UI(config)
 
-# Extend with plugin commands
-plugin.load_plugins(config, ui, configs.get_plugins(config))
-for p in plugin.get_plugins().values():
-    cmds.update(collections.OrderedDict([(p.name, p)]))
-#
+def execute(raw_args = sys.argv):
+    config = configs.read_config()
+    ui = UI(config)
 
-parser = argparse.ArgumentParser(description="research papers repository")
-subparsers = parser.add_subparsers(title="valid commands", dest="command")
+    # Extend with plugin commands
+    plugin.load_plugins(config, ui, configs.get_plugins(config))
+    for p in plugin.get_plugins().values():
+        cmds.update(collections.OrderedDict([(p.name, p)]))
 
-for cmd_mod in cmds.values():
-    subparser = cmd_mod.parser(subparsers, config)  # why do we return the subparser ?
+    parser = argparse.ArgumentParser(description="research papers repository")
+    subparsers = parser.add_subparsers(title="valid commands", dest="command")
+
+    for cmd_mod in cmds.values():
+        subparser = cmd_mod.parser(subparsers, config)  # why do we return the subparser ?
 
-def execute(raw_args = sys.argv):
     args = parser.parse_args(raw_args[1:])
     args.config = config
+
     args.ui = ui
     cmd = args.command
     del args.command
diff --git a/tests/test_usecase.py b/tests/test_usecase.py
index e62fc46..56b6740 100644
--- a/tests/test_usecase.py
+++ b/tests/test_usecase.py
@@ -4,33 +4,75 @@ import pkgutil
 
 import testenv
 import fake_filesystem
+import fake_filesystem_shutil
 
-import papers
-from papers import papers_cmd
+real_os = os
+real_open = open
+
+fake_os, fake_open, fake_shutil = None, None
+
+def _create_fake_fs():
+    global fake_os, fake_open, fake_shutil
 
-def create_fake_fs():
     fake_fs = fake_filesystem.FakeFilesystem()
     fake_os = fake_filesystem.FakeOsModule(fake_fs)
     fake_open = fake_filesystem.FakeFileOpen(fake_fs)
-    fake_fs.CreateFile('/Users/fabien/bla')
+    fake_shutil = fake_filesystem_shutil.FakeShutilModule(fake_fs)
+
+    fake_fs.CreateDirectory(fake_os.path.expanduser('~'))
     __builtins__['open'] = fake_open
     __builtins__['file'] = fake_open
 
-    for importer, modname, ispkg in pkgutil.walk_packages(path=papers.__path__,
-                                                      prefix=papers.__name__+'.',
-                                                      onerror=lambda x: None):
+    sys.modules['os'] = fake_os
+    sys.modules['shutil'] = fake_shutil
+
+    import papers
+    for importer, modname, ispkg in pkgutil.walk_packages(
+                                        path=papers.__path__,
+                                        prefix=papers.__name__+'.',
+                                        onerror=lambda x: None):
         md = __import__(modname, fromlist = 'dummy')
         md.os = fake_os
+        md.shutil = fake_shutil
 
+    return fake_fs
 
-class TestUseCases(unittest.TestCase):
+class TestInit(unittest.TestCase):
 
     def test_init(self):
-        create_fake_fs()
-        papers_md.execute_papers('papers init -p paper_test2'.split())
-
-    def test_init(self):
-        create_fake_fs()
+        fs = _create_fake_fs()
+        from papers import papers_cmd
         papers_cmd.execute('papers init -p paper_test2'.split())
+        self.assertEqual(set(fake_os.listdir('/paper_test2/')), {'bibdata', 'doc', 'meta', 'papers.yaml'})
+
+class TestAdd(unittest.TestCase):
+
+    def test_add(self):
+
+        fs = _create_fake_fs()
+        from papers import papers_cmd
+        papers_cmd.execute('papers init'.split())
+
+        with real_open('data/pagerank.bib', 'r') as f:
+            fs.CreateFile('/data/page.bib', contents = f.read())
+        with real_open('data/pagerank.pdf', 'r') as f:
+            fs.CreateFile('/data/page.pdf', contents = f.read())
+
+        papers_cmd.execute('papers add -b /data/page.bib -d /data/page.pdf'.split())
+
+
+class TestAdd2(unittest.TestCase):
+    def test_add2(self):
+
+        fs = _create_fake_fs()
+        from papers import papers_cmd
+        papers_cmd.execute('papers init -p /not_default'.split())
+
+        with real_open('data/pagerank.bib', 'r') as f:
+            fs.CreateFile('/data/page.bib', contents = f.read())
+        with real_open('data/pagerank.pdf', 'r') as f:
+            fs.CreateFile('/data/page.pdf', contents = f.read())
+
+        papers_cmd.execute('papers add -b /data/page.bib -d /data/page.pdf'.split())