Re: Filename quoting / parsing problem

Andreas Gruenbacher [off-list ref] writes:

Git quotes file names as documented in the git-diff manual page:

  TAB, LF, double quote and backslash characters in pathnames are represented
  as \t, \n, \" and \\, respectively.  If there is need for such substitution
  then the whole pathname is put in double quotes.

Spaces in file names currently do not trigger quoting.  (And \r triggers 
quoting even though the man page doesn't say so).

Any control character is quoted; the documentation quoted above lists only
the common ones that have non-octal representation.

        $ git init one
        Initialized empty Git repository in /var/tmp/gomi/one/.git/
        $ cd one
        $ >hello && git add hello && git commit -m 'hello'
        [master (root-commit) 5338884] hello
         0 files changed, 0 insertions(+), 0 deletions(-)
         create mode 100644 hello
        $ >'a^Afile' ; >'b file' ; 'c file '
        $ git add 'a^Afile' 'b file' 'c file '

In the above sequence that attempts to reproduce the issue, "^A" actually
is a byte with value \001 (typically you would type ^V^A to get it from
the terminal on the shell).  "^G" seems to get "\a" even though it is not
in the list (that is why I said "only the common ones" above).

        $ git ls-files -s | cat -e
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	"a\001file"$
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	b file$
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	c file $
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	hello$

I used "cat -e" to make it easier to see that "c file " not only has SP in
it but it has trailing space.  Let's try the result.

        $ git diff --cached | cat -e
        diff --git "a/a\001file" "b/a\001file"$
        new file mode 100644$
        index 0000000..e69de29$
        diff --git a/b file b/b file$
        new file mode 100644$
        index 0000000..e69de29$
        diff --git a/c file  b/c file $
        new file mode 100644$
        index 0000000..e69de29$
        $ git diff --cached >P.diff

And as you described, "b file" and "c file " are not quoted and they do
not have ---/+++ lines.

But observe this:

	$ git reset --hard
        $ ls
        P.diff	hello
	$ git ls-files -s
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	hello

We are now back in the state without any of these files, and P.diff records
a patch to recreate these three files, one with quoting and the other two
without.

	$ git apply --index P.diff
        $ git ls-files -s | cat -e
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	"a\001file"$
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	b file$
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	c file $
        100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 0	hello$

This demonstrates that The claim below is false, doesn't it?

Not parseable:
    diff --git a/baz  b/baz 
    new file mode 100644
    index 0000000..e69de29

Both "b file" and "c file " are parsed by "git apply" perfectly fine.