Re: git-status -- trying to understand all possible states

From: Junio C Hamano <gitster@pobox.com>
Date: Apr 1, 2014, 21:37 UTC
Message-ID: <xmqq4n2czq6n.fsf@gitster.dls.corp.google.com>
In-Reply-To: <4AF06B83-E928-4FE2-8094-F23CE3BA1EBC@toyland.org>

Michael Toy <michael@toyland.org> writes:

> Of the 24 possibilities (not counting ignored) in git-status,
> there are 7 that I can't figure out how to generate.

As the post [*1*] that triggered e92e9cd3 (Documentation improvements for the description of short format., 2010-04-23), which is where the bulk of the format description comes from, says, this is "Patches welcome" ;-) Some are just covering possible permutations and it is not surprising if they would not appear in practice.

> D           M    deleted from index

I doubt this is possible in practice; once you do not have the entry in the index, we do not even look at the working tree file, so it would be unusual to see M in the second column.

> D           D    unmerged, both deleted
> A           U    unmerged, added by us
> U           A    unmerged, added by them

    $ x="100644 $(git hash-object --stdin </dev/null)" &&
      printf "$x 2\tbar\n$x 1\tfoo\n$x 3\tbaz" |
      git update-index --index-info
    $ git status --short -suno
    AU bar
    UA baz
    DD foo
    $ git ls-files -u
    100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 2       bar
    100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 3       baz
    100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 1       foo

When you are using higher-level machinery to merge, "we added, they left it missing" (i.e. bar that has only stage #2) is automatically resolved to an addition by the trivial merge machinery. The "they added, we left it missing" (i.e. baz with only stage #3) case is identical. Also "both of us removed" (i.e. foo that has only stage #1) is resolved to a deletion by the trivial merge machinery. Hence you would not see these three unless you are developing Git using a low-level plumbing machinery.

[Reference]

*1* http://thread.gmane.org/gmane.comp.version-control.git/144455/focus=144468