More cases of neading to clean during execution

projects/vfs/src/python/vfs/impl.py

@@ -32,11 +32,14 @@ class Vfs(object):
                     if dest.is_symlink() and dest.readlink() == src:
                         continue
                     else:
+                        _log.warn(f"Replacing {dest}")
                         dest.unlink()
+                elif dest.is_dir():
+                    _log.warn(f"Replacing {dest}")
+                    rmtree(dest)
 
-                assert not dest.exists()
+                assert not dest.exists(), f"{dest} should not exist"
                 dest.symlink_to(src)
-                assert dest.exists()
 
             elif e[0] == "copy":
                 raise NotImplementedError()
@@ -47,6 +50,11 @@ class Vfs(object):
 
             elif e[0] == "mkdir":
                 _, dest = e
+                if dest.is_dir():
+                    continue
+                elif dest.exists() or dest.is_symlink():
+                    dest.unlink()
+
                 dest.mkdir(exist_ok=True)
 
             elif e[0] == "unlink":