424bef6b6 (smudge: check for known annexed inodes before checking
annex.largefiles, 2021-05-03) fixed a case where an unlocked annexed
file that annex.largefiles does not match could get its unchanged
content checked into git.  This was in response to
<https://git-annex.branchable.com/forum/one-off_unlocked_annex_files_that_go_against_large/>.

In a comment there, Joey said:

> I've made a change that seems to work, and will probably not break
> other cases, although this is a complex and subtle area.

I'm following up with a change in behavior flagged by a DataLad test.
As with most things in this area, I have a hard time reasoning about
what the expected behavior should be and whether it should be
considered a bug.  Here's the reproducer:

[[!format sh """
set -eu

cd "$(mktemp -d "${TMPDIR:-/tmp}"/ga-XXXXXXX)"

git version
git annex version | head -1

git init -q
git annex init

echo a >foo
git annex add foo
git commit --quiet -m 'add foo'

git annex unlock foo
printf '* annex.largefiles=nothing\n' >.gitattributes

sleep 1

git annex add foo
git commit -q -m 'commit unlocked' -- foo

set -x
export PS4='> '
git diff HEAD^- -- foo
git diff --cached
"""]]

Here's the output with 8.20210428:

```
git version 2.31.1.659.g12c5fe8677
git-annex version: 8.20210428
[...]
> git diff HEAD^- -- foo
diff --git a/foo b/foo
deleted file mode 120000
index 8a2a0c9..0000000
--- a/foo
+++ /dev/null
@@ -1 +0,0 @@
-.git/annex/objects/3z/F8/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7
\ No newline at end of file
diff --git a/foo b/foo
new file mode 100644
index 0000000..7898192
--- /dev/null
+++ b/foo
@@ -0,0 +1 @@
+a
> git diff --cached
```

And here's the output with a recent commit on master following
424bef6b6:

```
git version 2.31.1.659.g12c5fe8677
git-annex version: 8.20210429-ge811a50e2
[...]
> git diff HEAD^- -- foo
diff --git a/foo b/foo
deleted file mode 120000
index 8a2a0c9..0000000
--- a/foo
+++ /dev/null
@@ -1 +0,0 @@
-.git/annex/objects/3z/F8/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7
\ No newline at end of file
diff --git a/foo b/foo
new file mode 100644
index 0000000..3de500c
--- /dev/null
+++ b/foo
@@ -0,0 +1 @@
+/annex/objects/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7
> git diff --cached
diff --git a/foo b/foo
index 3de500c..7898192 100644
--- a/foo
+++ b/foo
@@ -1 +1 @@
-/annex/objects/SHA256E-s2--87428fc522803d31065e7bce3cf03fe475096631e5e07bbd7a0fde60c4cf25c7
+a
```

Before 424bef6b6, `git annex add foo + git commit ... foo` results in
a commit that has foo's content tracked in git.  After 424bef6b6, the
unlocked file is still recorded, and the switch to being tracked by
git ends up staged in the index.

The new behavior isn't seen if the pathspec is dropped from `git
commit`.  Also, without the sleep, it isn't triggered reliably
(presumably because the index and foo have the same mtime, bypassing
the clean filter).

Thanks for taking a look.

[[!meta author=kyle]]
[[!tag projects/datalad]]

> commit reverted; [[done]] --[[Joey]]
