vfs: include unique repo id in resolution cache key

[bup.git] / lib / bup / repo.py

diff --git a/lib/bup/repo.py b/lib/bup/repo.py
index 97547d539e481b776e915b05a2efe1d5e9929802..cc8a3fd2e7161043b2bb158b0c2d25b55081a28a 100644 (file)
--- a/lib/bup/repo.py
+++ b/lib/bup/repo.py
@@ -1,15 +1,29 @@
 
 from __future__ import absolute_import
+from os.path import realpath
 from functools import partial
 
 from bup import client, git
 
 
+_next_repo_id = 0
+_repo_ids = {}
+
+def _repo_id(key):
+    global _next_repo_id, _repo_ids
+    repo_id = _repo_ids.get(key)
+    if repo_id:
+        return repo_id
+    next_id = _next_repo_id = _next_repo_id + 1
+    _repo_ids[key] = next_id
+    return next_id
+
 class LocalRepo:
     def __init__(self, repo_dir=None):
-        self.repo_dir = repo_dir or git.repo()
+        self.repo_dir = realpath(repo_dir or git.repo())
         self._cp = git.cp(self.repo_dir)
         self.rev_list = partial(git.rev_list, repo_dir=self.repo_dir)
+        self._id = _repo_id(self.repo_dir)
 
     def close(self):
         pass
@@ -23,6 +37,12 @@ class LocalRepo:
     def __exit__(self, type, value, traceback):
         self.close()
 
+    def id(self):
+        """Return an identifier that differs from any other repository that
+        doesn't share the same repository-specific information
+        (e.g. refs, tags, etc.)."""
+        return self._id
+
     def cat(self, ref):
         """If ref does not exist, yield (None, None, None).  Otherwise yield
         (oidx, type, size), and then all of the data associated with
@@ -52,6 +72,7 @@ class RemoteRepo:
         self.address = address
         self.client = client.Client(address)
         self.rev_list = self.client.rev_list
+        self._id = _repo_id(self.address)
 
     def close(self):
         if self.client:
@@ -67,6 +88,12 @@ class RemoteRepo:
     def __exit__(self, type, value, traceback):
         self.close()
 
+    def id(self):
+        """Return an identifier that differs from any other repository that
+        doesn't share the same repository-specific information
+        (e.g. refs, tags, etc.)."""
+        return self._id
+
     def cat(self, ref):
         """If ref does not exist, yield (None, None, None).  Otherwise yield
         (oidx, type, size), and then all of the data associated with