Don't generate git patches that rename a file to multiple destinations
With this patch, instead of generating N renames, we'll generate
1 rename and N-1 copies.
Ideally the rename should come after the copies instead of before
them, but that'd be harder to do.
% new file
applying patch from stdin
% new empty file
applying patch from stdin
empty
% chmod +x
applying patch from stdin
% copy
applying patch from stdin
a
a
% rename
applying patch from stdin
copyx
empty
new
rename
% delete
applying patch from stdin
empty
new
rename
% regular diff
applying patch from stdin
% copy and modify
applying patch from stdin
a
a
b
a
a
% rename and modify
applying patch from stdin
copy2: No such file or directory
a
a
b
c
a
% one file renamed multiple times
applying patch from stdin
9 rename2 rename3 rename3-2 / rename3 (rename2)rename3-2 (rename2)
rename2: No such file or directory
rename3
rename3-2
a
a
b
c
a
a
a
b
c
a