doc/bugs/data_loss_on_Windows__58___git_annex_sync_--no-content_drops_last_copy_unexpectedly.mdwn

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+### Please describe the problem.
+A seemingly harmless script causes data loss by dropping last copy of file content.
+
+In my test this script only drops file content on Windows. On Linux it's working good, even on a crippled filesystem.
+
+### What steps will reproduce the problem?
+run the following script test.sh:
+[[!format sh """
+mkdir a
+cd a
+git init
+git annex init first
+mkdir folder
+echo foo > folder/1.txt
+git annex add .
+git annex sync
+cd ..
+git clone a b
+cd b
+git annex init second
+git annex sync
+cd ../a
+git remote add second ../b
+git annex sync
+git annex move --to second
+git annex sync
+mv folder folder1
+git annex add
+git annex sync
+cd ../b
+git annex sync
+"""]]
+
+### What version of git-annex are you using? On what operating system?
+git-annex version: 6.20161231-gc8eeb17
+
+Windows 10.0.14393 and also Windows 8
+
+### Please provide any additional information below.
+
+[[!format sh """
+# a complete transcript of the problem occurring.
+$ ./test.sh
+Initialized empty Git repository in A:/a/.git/
+init first
+  Detected a filesystem without fifo support.
+
+  Disabling ssh connection caching.
+
+  Detected a crippled filesystem.
+
+  Enabling direct mode.
+ok
+(recording state in git...)
+add folder/1.txt ok
+(recording state in git...)
+commit  ok
+Cloning into 'b'...
+done.
+init second
+  Detected a filesystem without fifo support.
+
+  Disabling ssh connection caching.
+
+  Detected a crippled filesystem.
+(merging origin/git-annex into git-annex...)
+(recording state in git...)
+
+  Enabling direct mode.
+ok
+(recording state in git...)
+commit  ok
+pull origin
+ok
+push origin
+Counting objects: 6, done.
+Delta compression using up to 8 threads.
+Compressing objects: 100% (5/5), done.
+Writing objects: 100% (6/6), 664 bytes | 0 bytes/s, done.
+Total 6 (delta 0), reused 0 (delta 0)
+To A:/a
+ * [new branch]      git-annex -> synced/git-annex
+ok
+commit  ok
+pull second
+From ../b
+ * [new branch]      annex/direct/master -> second/annex/direct/master
+ * [new branch]      git-annex           -> second/git-annex
+ * [new branch]      master              -> second/master
+ * [new branch]      synced/master       -> second/synced/master
+ok
+move folder/1.txt (to second...)
+1.txt
+              4 100%    0.00kB/s    0:00:00 (xfr#1, to-chk=0/1)
+(checksum...) ok
+(recording state in git...)
+commit  ok
+pull second
+remote: Counting objects: 5, done.
+remote: Compressing objects: 100% (4/4), done.
+remote: Total 5 (delta 1), reused 0 (delta 0)
+Unpacking objects: 100% (5/5), done.
+From ../b
+   fd774cb..1aba4de  git-annex  -> second/git-annex
+ok
+(merging second/git-annex into git-annex...)
+(recording state in git...)
+push second
+Counting objects: 10, done.
+Delta compression using up to 8 threads.
+Compressing objects: 100% (8/8), done.
+Writing objects: 100% (10/10), 827 bytes | 0 bytes/s, done.
+Total 10 (delta 3), reused 0 (delta 0)
+To ../b
+ * [new branch]      git-annex -> synced/git-annex
+ok
+add folder1/1.txt ok
+(recording state in git...)
+commit  (recording state in git...)
+ok
+pull second
+ok
+push second
+Counting objects: 7, done.
+Delta compression using up to 8 threads.
+Compressing objects: 100% (5/5), done.
+Writing objects: 100% (7/7), 687 bytes | 0 bytes/s, done.
+Total 7 (delta 0), reused 0 (delta 0)
+To ../b
+   7ba3e8a..ee8025b  git-annex -> synced/git-annex
+   0758cf9..6e91185  annex/direct/master -> synced/master
+ok
+commit  ok
+merge synced/master
+Updating 0758cf9..6e91185
+Fast-forward
+ {folder => folder1}/1.txt | 0
+ 1 file changed, 0 insertions(+), 0 deletions(-)
+ rename {folder => folder1}/1.txt (100%)
+error: duplicate parent 6e91185c7c64569b275a09be1a104a1d8955e1fb ignored
+ok
+pull origin
+From A:/a
+   0758cf9..6e91185  annex/direct/master -> origin/annex/direct/master
+   fd774cb..ee8025b  git-annex           -> origin/git-annex
+   0758cf9..6e91185  master              -> origin/master
+   0758cf9..6e91185  synced/master       -> origin/synced/master
+ok
+push origin
+Counting objects: 1, done.
+Writing objects: 100% (1/1), 185 bytes | 0 bytes/s, done.
+Total 1 (delta 0), reused 0 (delta 0)
+To A:/a
+   fd774cb..ee8025b  git-annex -> synced/git-annex
+   6e91185..a886805  annex/direct/master -> synced/master
+ok
+
+$ # script done here
+$ cd b
+$ git annex whereis
+whereis folder1/1.txt (1 copy)
+        2a9ef292-1729-4533-ac50-f68d2d0badb6 -- second [here]
+ok
+
+$ cat folder1/1.txt
+../.git/annex/objects/W5/55/SHA256E-s4--b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c.txt/SHA256E-s4--b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c.txt
+
+$ git annex get
+get folder1/1.txt (not available)
+  No other repository is known to contain the file.
+failed
+git-annex: get: 1 failed
+
+
+# End of transcript or log.
+"""]]
+
+
+### Conclusion
+
+I'm so attracted to git-annex's idea, but seems it's still not robust enough to use on Windows platform - v5 direct mode repo is as far as I can get, yet it still throws away my data like this...