git query file permissions of a file in an arbitrary commit

$ git init
$ date > file1.txt
$ git add .
$ git commit -a -m "ok"
$ git log --raw file1.txt

Last cmd works ok. I get:

:000000 100644 0000000... c0d0a60... A  file1.txt

But if I do:

$ git log --raw HEAD:file1开发者_如何学Go.txt

I get nothing.

What am I missing? I need to get the second form working so that I can query the perms of the file in any arbitrary commit, not just the currently checkout working tree.

The log command takes a set-of-commits and a path. In the first form you are giving it a path and set-of-commits defaults to HEAD (all commits reachable from HEAD). In the second form you are giving it an object id that does not name a commit, but is not a path either, so it can't do anything.

You need to give it a commit set and the path:

• Commit set containing just one commit is commitish^!. So in your case HEAD^!.
• Path is still just file1.txt

So use:

git log --raw HEAD^! file1.txt

Of course (as J-16 SDiZ correctly noted) using git ls-tree, which is designed for the purpose, is better than abusing git log. So that would be:

git ls-tree HEAD file1.txt

unlike log, ls-tree takes a treeis (of which a commitish is a special-case), so you don't have to add funny suffixes like ^!.

You need:

git log --raw HEAD^1..HEAD file1.txt