initial report about failure to commit

doc/bugs/cannot_commit___34__annex_add__34__ed_modified_file_which_switched_its_largefile_status_to_be_committed_to_git_now.mdwn

@@ -0,0 +1,70 @@
+### Please describe the problem.
+
+Leads to a failure of 'git commit' upon attempt to commit a file which went from "largefile" to small, according to .gitattributes settings, if we `git annex add file` before committing the change.
+
+### What version of git-annex are you using? On what operating system?
+
+6.20180720+gitg03978571f-1~ndall+1
+
+### Please provide any additional information below.
+
+Here is a full script to reproduce it:
+[[!format sh """
+#!/bin/bash
+
+set -ex
+
+builtin cd /tmp; 
+
+if [ -e /tmp/repo ]; then
+    chmod -R +w /tmp/repo; 
+    rm -rf /tmp/repo; 
+fi
+mkdir /tmp/repo; 
+cd /tmp/repo; 
+git init; 
+git annex init; 
+echo '* annex.largefiles=(largerthan=5b)' >.gitattributes; 
+git add .gitattributes; 
+git commit -m 'added .gitattri'; 
+echo 123456 > file; 
+git annex add file; 
+git commit -m add1; 
+ls -l; 
+
+git annex unlock file; 
+echo 123 >| file
+git annex add file
+
+# this would work but commit to git-annex, not git despite .gitattributes settings
+# git commit -m edit -a 
+# This one would fail to commit at all, complaining about "partial commit"
+git commit -m edit file
+ls -l file; 
+
+git status
+
+
+"""]]
+
+which leads to 
+[[!format sh """
+...
++ git annex add file
+add file (non-large file; adding content to git repository) ok
+add file (non-large file; adding content to git repository) ok
+(recording state in git...)
++ git commit -m edit file
+git-annex: Cannot make a partial commit with unlocked annexed files. You should `git annex add` the files you want to commit, and then run git commit.
+"""]]
+
+additional observations:
+
+- works fine if remains large file (e.g. we just append to it)
+- does not fail if we do `git commit -a` not `git commit file`, but it commits it to annex not to git, despite previous `git annex add` message rightfully says that "non-large file; adding content to git repository" 
+
+Expected behavior:
+- have consistent behavior between `commit -a` and `commit file`
+- commit without a failure, committing to git (since .gitattributes instructs so and even `git annex add` reports that)
+
+[[!meta author=yoh]]