On 07/21, Johannes Schindelin via GitGitGadget wrote:
> From: Johannes Schindelin <johannes.schindelin@xxxxxx>
>
> Just like tbdiff, we now show the diff between matching patches. This is
> a "diff of two diffs", so it can be a bit daunting to read for the
> beginner.
>
> An alternative would be to display an interdiff, i.e. the hypothetical
> diff which is the result of first reverting the old diff and then
> applying the new diff.
>
> Especially when rebasing often, an interdiff is often not feasible,
> though: if the old diff cannot be applied in reverse (due to a moving
> upstream), an interdiff can simply not be inferred.
>
> This commit brings `range-diff` closer to feature parity with regard
> to tbdiff.
>
> To make `git range-diff` respect e.g. color.diff.* settings, we have
> to adjust git_branch_config() accordingly.
>
> Note: while we now parse diff options such as --color, the effect is not
> yet the same as in tbdiff, where also the commit pairs would be colored.
> This is left for a later commit.
>
> Note also: while tbdiff accepts the `--no-patches` option to suppress
> these diffs between patches, we prefer the `-s` option that is
> automatically supported via our use of diff_opt_parse().
One slightly unfortunate thing here is that we don't show these
options in 'git range-diff -h', which would be nice to have. I don't
know if that's possible in git right now, if it's not easily possible,
I definitely wouldn't want to delay this series for that, and we could
just add it to the list of possible future enhancements that other
people mentioned.
> Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx>
> ---
> builtin/range-diff.c | 25 ++++++++++++++++++++++---
> range-diff.c | 34 +++++++++++++++++++++++++++++++---
> range-diff.h | 4 +++-
> 3 files changed, 56 insertions(+), 7 deletions(-)
>
> [...]
>
> diff --git a/range-diff.c b/range-diff.c
> index 2d94200d3..71883a4b7 100644
> --- a/range-diff.c
> +++ b/range-diff.c
> @@ -6,6 +6,7 @@
> #include "hashmap.h"
> #include "xdiff-interface.h"
> #include "linear-assignment.h"
> +#include "diffcore.h"
>
> struct patch_util {
> /* For the search for an exact match */
> @@ -258,7 +259,31 @@ static const char *short_oid(struct patch_util *util)
> return find_unique_abbrev(&util->oid, DEFAULT_ABBREV);
> }
>
> -static void output(struct string_list *a, struct string_list *b)
> +static struct diff_filespec *get_filespec(const char *name, const char *p)
> +{
> + struct diff_filespec *spec = alloc_filespec(name);
> +
> + fill_filespec(spec, &null_oid, 0, 0644);
> + spec->data = (char *)p;
> + spec->size = strlen(p);
> + spec->should_munmap = 0;
> + spec->is_stdin = 1;
> +
> + return spec;
> +}
> +
> +static void patch_diff(const char *a, const char *b,
> + struct diff_options *diffopt)
> +{
> + diff_queue(&diff_queued_diff,
> + get_filespec("a", a), get_filespec("b", b));
> +
> + diffcore_std(diffopt);
> + diff_flush(diffopt);
> +}
> +
> +static void output(struct string_list *a, struct string_list *b,
> + struct diff_options *diffopt)
> {
> int i = 0, j = 0;
>
> @@ -300,6 +325,9 @@ static void output(struct string_list *a, struct string_list *b)
> printf("%d: %s ! %d: %s\n",
> b_util->matching + 1, short_oid(a_util),
> j + 1, short_oid(b_util));
> + if (!(diffopt->output_format & DIFF_FORMAT_NO_OUTPUT))
Looking at this line, it looks like it would be easy to support
'--no-patches' as well, which may be slightly easier to understand that
'-s' to someone new to the command. But again that can be added later
if someone actually cares about it.
> + patch_diff(a->items[b_util->matching].string,
> + b->items[j].string, diffopt);
> a_util->shown = 1;
> j++;
> }
> @@ -307,7 +335,7 @@ static void output(struct string_list *a, struct string_list *b)
> }
>
> int show_range_diff(const char *range1, const char *range2,
> - int creation_factor)
> + int creation_factor, struct diff_options *diffopt)
> {
> int res = 0;
>
> @@ -322,7 +350,7 @@ int show_range_diff(const char *range1, const char *range2,
> if (!res) {
> find_exact_matches(&branch1, &branch2);
> get_correspondences(&branch1, &branch2, creation_factor);
> - output(&branch1, &branch2);
> + output(&branch1, &branch2, diffopt);
> }
>
> string_list_clear(&branch1, 1);
> diff --git a/range-diff.h b/range-diff.h
> index dd30449c4..aea9d43f3 100644
> --- a/range-diff.h
> +++ b/range-diff.h
> @@ -1,7 +1,9 @@
> #ifndef BRANCH_DIFF_H
> #define BRANCH_DIFF_H
>
> +#include "diff.h"
> +
> int show_range_diff(const char *range1, const char *range2,
> - int creation_factor);
> + int creation_factor, struct diff_options *diffopt);
>
> #endif
> --
> gitgitgadget
>
