Re: [PATCH 03/18] branch-diff: first rudimentary implementation

> At this stage, `git branch-diff` can determine corresponding commits of
> two related commit ranges. This makes use of the recently introduced
> implementation of the Hungarian algorithm.
> 
> The core of this patch is a straight port of the ideas of tbdiff, the
> seemingly dormant project at https://github.com/trast/tbdiff.
> 
> The output does not at all match `tbdiff`'s output yet, as this patch
> really concentrates on getting the patch matching part right.
> 
> Note: due to differences in the diff algorithm (`tbdiff` uses the
> Pythong module `difflib`, Git uses its xdiff fork), the cost matrix
> calculated by `branch-diff` is different (but very similar) to the one
> calculated by `tbdiff`. Therefore, it is possible that they find
> different matching commits in corner cases (e.g. when a patch was split
> into two patches of roughly equal length).
> 
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
>  builtin/branch-diff.c | 337 +++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 334 insertions(+), 3 deletions(-)
> 
> diff --git a/builtin/branch-diff.c b/builtin/branch-diff.c
> index 97266cd326d..02dc06a57ca 100644
> --- a/builtin/branch-diff.c
> +++ b/builtin/branch-diff.c
> @@ -1,13 +1,17 @@
>  #include "cache.h"
>  #include "parse-options.h"
> +#include "string-list.h"
> +#include "run-command.h"
> +#include "argv-array.h"
> +#include "hashmap.h"
> +#include "xdiff-interface.h"
> +#include "hungarian.h"
>  
>  static const char * const builtin_branch_diff_usage[] = {
>  	N_("git rebase--helper [<options>] ( A..B C..D | A...B | base A B )"),
>  	NULL
>  };
>  
> -#define COLOR_DUAL_MODE 2
> -