doc/bugs/git_annex_unused_considers_remote_branches_which_makes_it_inconsistent.mdwn

@@ -0,0 +1,100 @@
+The "git annex unused" command considers remote branches as well as local branches.  This means that an
+object may be considered unused or not depending on what remotes are present and when they were last synced.
+
+I ran into this issue when experimenting with using repos on removable storage.  I'll post more about
+what I was trying to do in the forum.  I'm posting this in bugs as I believe the inconsistent behavior
+should probably be considered a bug.
+
+#What steps will reproduce the problem?
+
+Here is a sample session illustrating the problem.  At the end, you can see that the object is
+not shown as unused, then the remote is removed and it is shown as unused, then the remote is added
+back and the file is once again not shown as unused.
+
+    /tmp/git $ mkdir 1 2
+    /tmp/git $ cd 1
+    /tmp/git/1 $ git init
+    Initialized empty Git repository in /tmp/git/1/.git/
+    /tmp/git/1 $ git annex init 1
+    init 1 ok
+    (Recording state in git...)
+    /tmp/git/1 $ git remote add 2 ../2
+    /tmp/git/1 $ dd if=/dev/urandom of=file.bin count=100
+    100+0 records in
+    100+0 records out
+    51200 bytes (51 kB) copied, 0.0113172 s, 4.5 MB/s
+    /tmp/git/1 $ git annex add file.bin 
+    add file.bin (checksum...) ok
+    (Recording state in git...)
+    /tmp/git/1 $ git commit -m 'added file'
+    [master (root-commit) 3c1ad30] added file
+     1 files changed, 1 insertions(+), 0 deletions(-)
+     create mode 120000 file.bin
+    /tmp/git/1 $ cd ../2
+    /tmp/git/2 $ git init
+    Initialized empty Git repository in /tmp/git/2/.git/
+    /tmp/git/2 $ git annex init 2
+    init 2 ok
+    (Recording state in git...)
+    /tmp/git/2 $ git remote add 1 ../1
+    /tmp/git/2 $ git fetch 1
+    warning: no common commits
+    remote: Counting objects: 13, done.
+    remote: Compressing objects: 100% (9/9), done.
+    remote: Total 13 (delta 0), reused 0 (delta 0)
+    Unpacking objects: 100% (13/13), done.
+    From ../1
+     * [new branch]      git-annex  -> 1/git-annex
+     * [new branch]      master     -> 1/master
+    /tmp/git/2 $ git checkout -b master 1/master
+    Branch master set up to track remote branch master from 1.
+    Already on 'master'
+    /tmp/git/2 $ cd ../1
+    /tmp/git/1 $ git fetch 2
+    remote: Counting objects: 5, done.
+    remote: Compressing objects: 100% (3/3), done.
+    remote: Total 5 (delta 0), reused 0 (delta 0)
+    Unpacking objects: 100% (5/5), done.
+    From ../2
+     * [new branch]      git-annex  -> 2/git-annex
+     * [new branch]      master     -> 2/master
+    /tmp/git/1 $ git rm file.bin 
+    rm 'file.bin'
+    /tmp/git/1 $ git commit -m 'rmed file'
+    [master ab242b0] rmed file
+     1 files changed, 0 insertions(+), 1 deletions(-)
+     delete mode 120000 file.bin
+    /tmp/git/1 $ git annex unused
+    unused . (checking for unused data...) (checking master...) (checking 2/master...) ok
+    /tmp/git/1 $ git remote rm 2
+    /tmp/git/1 $ git annex unused
+    unused . (checking for unused data...) (checking master...) 
+      Some annexed data is no longer used by any files:
+        NUMBER  KEY
+        1       SHA256E-s51200--e400e5abea095ad4364d8f97c5fe1a3f8a6db670b2dfee951d7c9674afc9a21d.bin
+      (To see where data was previously used, try: git log --stat -S'KEY')
+      
+      To remove unwanted data: git-annex dropunused NUMBER
+      
+    ok
+    /tmp/git/1 $ git remote add 2 ../2
+    /tmp/git/1 $ git fetch 2
+    From ../2
+     * [new branch]      git-annex  -> 2/git-annex
+     * [new branch]      master     -> 2/master
+    /tmp/git/1 $ git annex unused
+    unused . (checking for unused data...) (checking master...) (checking 2/master...) ok
+    /tmp/git/1 $ 
+
+
+#What is the expected output? What do you see instead?
+
+I expected that the object's unused status would not change based on which remotes this particular
+repo knows about.  In other words, I expected the unused status to be based on the local branches
+and possibly information in the git-annex branch.
+
+#What version of git-annex are you using? On what operating system?
+
+Gentoo Linux, git annex version 3.20121211
+
+#Please provide any additional information below.