| Message ID | pull.1734.git.1731000007391.gitgitgadget@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | range-diff: optionally include merge commits' diffs in the analysis | expand |
"Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com> writes: > Let's add corresponding support for `git range-diff`, too. This makes it > more convenient to spot differences between iterations of non-linear > contributions, where so-called "evil merges" are sometimes necessary and > need to be reviewed, too. Nice addition. As the "diff of the diff" outer diff part would be two-"blob" diff, we won't have to worry about this option causing confusions to users, unlike things like "-U8", to which layer of diffs the option would apply. Will queue. Thanks.
Am 07.11.24 um 18:20 schrieb Johannes Schindelin via GitGitGadget: > +--diff-merges=<format>:: > + Instead of ignoring merge commits, generate diffs for them using the > + corresponding `--diff-merges=<format>` option of linkgit:git-log[1], > + and include them in the comparison. > ++ > +Note: Some of the formats supported by linkgit:git-log[1] make less sense in > +the context of the `range-diff` command than other formats, so choose wisely! Can we please be a bit more specific which options are usable or which are not usable? Perhaps you even mean to say that 'first-parent' is the only one that makes sense? At a minimum, we should mention that it is the one that makes most sense (if that is the case). -- Hannes
Hi Hannes On Fri, 8 Nov 2024, Johannes Sixt wrote: > Am 07.11.24 um 18:20 schrieb Johannes Schindelin via GitGitGadget: > > +--diff-merges=<format>:: > > + Instead of ignoring merge commits, generate diffs for them using the > > + corresponding `--diff-merges=<format>` option of linkgit:git-log[1], > > + and include them in the comparison. > > ++ > > +Note: Some of the formats supported by linkgit:git-log[1] make less sense in > > +the context of the `range-diff` command than other formats, so choose wisely! > > Can we please be a bit more specific which options are usable or which > are not usable? There are a couple of reasons: - Most importantly: I had not even studied that question in depth when I wrote the original patch, and not even when I submitted the first iteration. In my reviews of branch thickets, I used `--diff-merges=1` and it served my needs well. Therefore I can speak to this mode, but not really to the other modes. - Which options are usable or not may lack a universally-correct answer. One person might find `--diff-merges=separate` confusing while the next person may find it quite useful. - If the documentation points out an unsuitable mode, then an obvious follow-up wish would be to reject this mode in the command, with an error message. Some users might, however, need precisely this mode, so I am loathe to do that. Maybe this compromise: Change the "Note:" to recommend the `first-parent` mode, with a bit more explanation why that is so (it is consistent with the idea that a merge is kind of a "meta patch", comprising all the merged commits' patches, which is equivalent to the first-parent diff). > Perhaps you even mean to say that 'first-parent' is the only one that > makes sense? I would not go _so_ far as to say that. Before submitting the patch yesterday, I played a little with a few modes, using the commit graph as per the new t3206 test case. What that test case range-diffs looks like this: - * - changeA - changeB ------------ \ \ \ \ conflict \ \ / \ rename - changeA - changeB ----- clean In other words, the main branch modifies a file's contents twice, the topic branch renames it first, then makes the same modifications. The clean merge simply merges the topic, which makes the main branch tree-same to the topic branch. The conflicting merge misses the tip commit of the topic branch, i.e. changeB on the renamed file. The result is tree-same to the clean merge because changeB on the non-renamed file is already part of the main branch. Out of habit, I used `--diff-merge=first-parent` in the new test case, whose output reiterates what I just said: both merges introduce the same first-parent diff (renaming the file, no other changes): 1: 1e6226b < -: ------- s/12/B/ 2: 043e738 = 1: 6ddec15 merge What about `separate`? 2: 043e738 = 1: 6ddec15 merge 1: 1e6226b ! 2: 6ddec15 s/12/B/ @@ ## Metadata ## -Author: Thomas Rast <trast@inf.ethz.ch> +Author: A U Thor <author@example.com> ## Commit message ## - s/12/B/ + merge ## renamed-file ## @@ renamed-file: A This might look confusing at first because there are two merge diffs on the right-hand side, but only one on the left-hand side. But that is all good because the diff of the clean merge between merge head and merge is empty and therefore not shown. And the `range-diff` demonstrates that the conflicting merge had to recapitulate the tip commit of the `renamed-file` topic branch. The `combined` and `dense-combined` modes produce identical output to `first-parent` in this instance, which is expected. Now, let's use `remerge`, which should be illuminating with regards to "evil merges" [*1*], as it shows what was done on top of the automatic merge: 1: 1e6226b < -: ------- s/12/B/ 2: 043e738 < -: ------- merge -: ------- > 1: 6ddec15 merge Huh. That is a bit surprising at first. Let's use a higher creation factor to ask `range-diff` to match correspondences more loosely (I used 999, which kinda forces even non-sensical pairings): 1: 1e6226b ! 1: 6ddec15 s/12/B/ @@ ## Metadata ## -Author: Thomas Rast <trast@inf.ethz.ch> +Author: A U Thor <author@example.com> ## Commit message ## - s/12/B/ + merge ## renamed-file ## + remerge CONFLICT (content): Merge conflict in renamed-file + index 3f1c0da..25ddf7a 100644 + --- renamed-file + +++ renamed-file @@ renamed-file: A 9 10 B +-<<<<<<< 2901f77 (s/12/B/):file + B +-======= -12 -+B +->>>>>>> 3ce7af6 (s/11/B/):renamed-file 13 14 15 2: 043e738 < -: ------- merge (Note that if you repeat this experiment, you will see something different due to a bug in `--remerge-diff` that I will fix separately.) Hold on, that looks wrong! It is actually not wrong, `range-diff` just finds the changeB a better pairing than the merge commit with an empty diff... So: This mode can be useful to detect where merge conflicts had to be resolved. In short, I think that in `range-diff`'s context all of these modes have merit, depending on a particular use case. It's just that `first-parent` is probably the most natural to use in the common case. > At a minimum, we should mention that it is the one that makes most sense > (if that is the case). Yeah, I'll go with that and drop saying anything about other modes. Ciao, Johannes Footnote *1*: We should really find a much better name for this than "evil merge". There is nothing evil about me having to add `#include "environment.h"` in v2.45.1^, for example. It was necessary so that the code would build. Tedious, yes, but not evil.
Johannes Sixt <j6t@kdbg.org> writes: > Am 07.11.24 um 18:20 schrieb Johannes Schindelin via GitGitGadget: >> +--diff-merges=<format>:: >> + Instead of ignoring merge commits, generate diffs for them using the >> + corresponding `--diff-merges=<format>` option of linkgit:git-log[1], >> + and include them in the comparison. >> ++ >> +Note: Some of the formats supported by linkgit:git-log[1] make less sense in >> +the context of the `range-diff` command than other formats, so choose wisely! > > Can we please be a bit more specific which options are usable or which > are not usable? Perhaps you even mean to say that 'first-parent' is the > only one that makes sense? At a minimum, we should mention that it is > the one that makes most sense (if that is the case). Good suggestion. I am curious to see how well things like "--cc" and "--remerge-diff" fare in this use case. I suspect that in a case where the original round forgot to make necessary semantic conflict resolutions (aka "evil merge") that the new round has, all of them (including the "--first-parent") would essentially show the same change, but what is shown in such a case would be more readable with "--first-parent" by treating a merge as if it were just a single parent commit making a lot of changes, iow, merely one among other commits with equal footing.
On Thu, Nov 7, 2024 at 9:20 AM Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com> wrote: > > From: Johannes Schindelin <johannes.schindelin@gmx.de> > > The `git log` command already offers support for including diffs for > merges, via the `--diff-merges=<format>` option. > > Let's add corresponding support for `git range-diff`, too. This makes it > more convenient to spot differences between iterations of non-linear > contributions, where so-called "evil merges" are sometimes necessary and > need to be reviewed, too. > > In my code reviews, I found the `--diff-merges=first-parent` option > particularly useful. Curious. Wouldn't --diff-merges=remerge-diff be more useful if you are particularly interested in so-called "evil merges" and whether they remain "evil" (i.e. empty remerge-diff) or gain additional bits of "evilness" (i.e. more changes shown in the remerge-diff)? first-parent would seem more like a workaround in such a case. Let me explain; first, let me refer to the result that you'd get after merging with no human changes (i.e. a non-evil merge) as a hypothetical "auto-merge" commit. Now, --diff-merges=first-parent could generally be broken down as the combination of diff from first parent to auto-merge + diff from auto-merge to evil-merge (even if the auto-merge wasn't actually recorded anywhere and is just a theoretical construct). Now, you aren't looking at a first-parent diff directly, you are diffing two first-parent diffs. In particular, you are comparing: pre-rebase first-parent diff = diff from first parent of merge to the auto-merge + diff from auto-merge to evil-merge to post-rebase first-parent diff = diff from first parent of merge to the auto-merge + diff from auto-merge to evil-merge Assuming you didn't drop or insert or modify any commits as part of the rebase, then the two "diff from first parent of merge to the auto-merge" should match. Since they match, taking the difference of these two causes that part to cancel out, meaning you are left just looking at the differences in the "evilness" of the actual merge. But if you did make other changes while rebasing, maybe dropping or tweaking a commit, then suddenly you aren't just looking at differences in the "evilness" of the actual merge anymore; it's mixed with those other changes making it more challenging to review and easy to miss the parts you are looking for. If you want to look for differences in whether the merge commit in question has changes other than those that a simple "git merge" would make, remerge-diff seems like a better choice. > Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> > --- > Support diff merges option in range diff > > The git range-diff command does the same with merge commits as git > rebase: It ignores them. > > However, when comparing branch thickets it can be quite illuminating to > watch out for inadvertent changes in merge commits, in particular when > some "evil" merges have been replayed, i.e. merges that needed to > introduce changes outside of the merge conflicts (e.g. when one branch > changed a function's signature and another branch introduced a caller of > said function), in case the replayed merge is no longer "evil" and > therefore potentially incorrect. > > Let's introduce support for the --diff-merges option that is passed > through to those git log commands. > > I had a need for this earlier this year and got it working, leaving the > GitGitGadget PR in a draft mode. Phil Blain found it and kindly > nerd-sniped me into readying it for submitting, so say thanks to Phil! > > Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1734%2Fdscho%2Fsupport-diff-merges-option-in-range-diff-v1 > Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1734/dscho/support-diff-merges-option-in-range-diff-v1 > Pull-Request: https://github.com/gitgitgadget/git/pull/1734 > > Documentation/git-range-diff.txt | 10 +++++++++- > builtin/range-diff.c | 11 +++++++++++ > range-diff.c | 15 +++++++++++---- > range-diff.h | 1 + > t/t3206-range-diff.sh | 16 ++++++++++++++++ > 5 files changed, 48 insertions(+), 5 deletions(-) > > diff --git a/Documentation/git-range-diff.txt b/Documentation/git-range-diff.txt > index fbdbe0befeb..a964e856c3c 100644 > --- a/Documentation/git-range-diff.txt > +++ b/Documentation/git-range-diff.txt > @@ -10,7 +10,7 @@ SYNOPSIS > [verse] > 'git range-diff' [--color=[<when>]] [--no-color] [<diff-options>] > [--no-dual-color] [--creation-factor=<factor>] > - [--left-only | --right-only] > + [--left-only | --right-only] [--diff-merges=<format>] > ( <range1> <range2> | <rev1>...<rev2> | <base> <rev1> <rev2> ) > [[--] <path>...] > > @@ -81,6 +81,14 @@ to revert to color all lines according to the outer diff markers > Suppress commits that are missing from the second specified range > (or the "right range" when using the `<rev1>...<rev2>` format). > > +--diff-merges=<format>:: > + Instead of ignoring merge commits, generate diffs for them using the > + corresponding `--diff-merges=<format>` option of linkgit:git-log[1], > + and include them in the comparison. > ++ > +Note: Some of the formats supported by linkgit:git-log[1] make less sense in > +the context of the `range-diff` command than other formats, so choose wisely! > + Indeed. :-) > --[no-]notes[=<ref>]:: > This flag is passed to the `git log` program > (see linkgit:git-log[1]) that generates the patches. > diff --git a/builtin/range-diff.c b/builtin/range-diff.c > index 1b33ab66a7b..e41719e0f0d 100644 > --- a/builtin/range-diff.c > +++ b/builtin/range-diff.c > @@ -21,6 +21,7 @@ int cmd_range_diff(int argc, > { > struct diff_options diffopt = { NULL }; > struct strvec other_arg = STRVEC_INIT; > + struct strvec diff_merges_arg = STRVEC_INIT; > struct range_diff_options range_diff_opts = { > .creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT, > .diffopt = &diffopt, > @@ -36,6 +37,9 @@ int cmd_range_diff(int argc, > OPT_PASSTHRU_ARGV(0, "notes", &other_arg, > N_("notes"), N_("passed to 'git log'"), > PARSE_OPT_OPTARG), > + OPT_PASSTHRU_ARGV(0, "diff-merges", &diff_merges_arg, > + N_("style"), N_("passed to 'git log'"), > + PARSE_OPT_OPTARG), > OPT_BOOL(0, "left-only", &left_only, > N_("only emit output related to the first range")), > OPT_BOOL(0, "right-only", &right_only, > @@ -62,6 +66,12 @@ int cmd_range_diff(int argc, > if (!simple_color) > diffopt.use_color = 1; > > + /* If `--diff-merges` was specified, imply `--merges` */ > + if (diff_merges_arg.nr) { > + range_diff_opts.include_merges = 1; > + strvec_pushv(&other_arg, diff_merges_arg.v); > + } > + > for (i = 0; i < argc; i++) > if (!strcmp(argv[i], "--")) { > dash_dash = i; > @@ -155,6 +165,7 @@ int cmd_range_diff(int argc, > res = show_range_diff(range1.buf, range2.buf, &range_diff_opts); > > strvec_clear(&other_arg); > + strvec_clear(&diff_merges_arg); > strbuf_release(&range1); > strbuf_release(&range2); > > diff --git a/range-diff.c b/range-diff.c > index bbb0952264b..9e59733059b 100644 > --- a/range-diff.c > +++ b/range-diff.c > @@ -38,7 +38,8 @@ struct patch_util { > * as struct object_id (will need to be free()d). > */ > static int read_patches(const char *range, struct string_list *list, > - const struct strvec *other_arg) > + const struct strvec *other_arg, > + unsigned int include_merges) > { > struct child_process cp = CHILD_PROCESS_INIT; > struct strbuf buf = STRBUF_INIT, contents = STRBUF_INIT; > @@ -49,7 +50,7 @@ static int read_patches(const char *range, struct string_list *list, > size_t size; > int ret = -1; > > - strvec_pushl(&cp.args, "log", "--no-color", "-p", "--no-merges", > + strvec_pushl(&cp.args, "log", "--no-color", "-p", > "--reverse", "--date-order", "--decorate=no", > "--no-prefix", "--submodule=short", > /* > @@ -64,6 +65,8 @@ static int read_patches(const char *range, struct string_list *list, > "--pretty=medium", > "--show-notes-by-default", > NULL); > > -- Hannes > > > + if (!include_merges) > + strvec_push(&cp.args, "--no-merges"); > strvec_push(&cp.args, range); > if (other_arg) > strvec_pushv(&cp.args, other_arg->v); > @@ -96,11 +99,14 @@ static int read_patches(const char *range, struct string_list *list, > } > > if (skip_prefix(line, "commit ", &p)) { > + char *q; > if (util) { > string_list_append(list, buf.buf)->util = util; > strbuf_reset(&buf); > } > CALLOC_ARRAY(util, 1); > + if (include_merges && (q = strstr(p, " (from "))) > + *q = '\0'; > if (repo_get_oid(the_repository, p, &util->oid)) { > error(_("could not parse commit '%s'"), p); > FREE_AND_NULL(util); > @@ -571,13 +577,14 @@ int show_range_diff(const char *range1, const char *range2, > > struct string_list branch1 = STRING_LIST_INIT_DUP; > struct string_list branch2 = STRING_LIST_INIT_DUP; > + unsigned int include_merges = range_diff_opts->include_merges; > > if (range_diff_opts->left_only && range_diff_opts->right_only) > res = error(_("options '%s' and '%s' cannot be used together"), "--left-only", "--right-only"); > > - if (!res && read_patches(range1, &branch1, range_diff_opts->other_arg)) > + if (!res && read_patches(range1, &branch1, range_diff_opts->other_arg, include_merges)) > res = error(_("could not parse log for '%s'"), range1); > - if (!res && read_patches(range2, &branch2, range_diff_opts->other_arg)) > + if (!res && read_patches(range2, &branch2, range_diff_opts->other_arg, include_merges)) > res = error(_("could not parse log for '%s'"), range2); > > if (!res) { > diff --git a/range-diff.h b/range-diff.h > index 2f69f6a434d..cd85000b5a0 100644 > --- a/range-diff.h > +++ b/range-diff.h > @@ -16,6 +16,7 @@ struct range_diff_options { > int creation_factor; > unsigned dual_color:1; > unsigned left_only:1, right_only:1; > + unsigned include_merges:1; > const struct diff_options *diffopt; /* may be NULL */ > const struct strvec *other_arg; /* may be NULL */ > }; > diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh > index 86010931ab6..c18a3fdab83 100755 > --- a/t/t3206-range-diff.sh > +++ b/t/t3206-range-diff.sh > @@ -909,4 +909,20 @@ test_expect_success 'submodule changes are shown irrespective of diff.submodule' > test_cmp expect actual > ' > > +test_expect_success '--diff-merges' ' > + renamed_oid=$(git rev-parse --short renamed-file) && > + tree=$(git merge-tree unmodified renamed-file) && > + clean=$(git commit-tree -m merge -p unmodified -p renamed-file $tree) && > + clean_oid=$(git rev-parse --short $clean) && > + conflict=$(git commit-tree -m merge -p unmodified -p renamed-file^ $tree) && > + conflict_oid=$(git rev-parse --short $conflict) && > + > + git range-diff --diff-merges=1 $clean...$conflict >actual && > + cat >expect <<-EOF && > + 1: $renamed_oid < -: ------- s/12/B/ > + 2: $clean_oid = 1: $conflict_oid merge > + EOF > + test_cmp expect actual > +' > + > test_done > > base-commit: 777489f9e09c8d0dd6b12f9d90de6376330577a2 > -- > gitgitgadget Didn't spot any problems with the patch itself.
diff --git a/Documentation/git-range-diff.txt b/Documentation/git-range-diff.txt index fbdbe0befeb..a964e856c3c 100644 --- a/Documentation/git-range-diff.txt +++ b/Documentation/git-range-diff.txt @@ -10,7 +10,7 @@ SYNOPSIS [verse] 'git range-diff' [--color=[<when>]] [--no-color] [<diff-options>] [--no-dual-color] [--creation-factor=<factor>] - [--left-only | --right-only] + [--left-only | --right-only] [--diff-merges=<format>] ( <range1> <range2> | <rev1>...<rev2> | <base> <rev1> <rev2> ) [[--] <path>...] @@ -81,6 +81,14 @@ to revert to color all lines according to the outer diff markers Suppress commits that are missing from the second specified range (or the "right range" when using the `<rev1>...<rev2>` format). +--diff-merges=<format>:: + Instead of ignoring merge commits, generate diffs for them using the + corresponding `--diff-merges=<format>` option of linkgit:git-log[1], + and include them in the comparison. ++ +Note: Some of the formats supported by linkgit:git-log[1] make less sense in +the context of the `range-diff` command than other formats, so choose wisely! + --[no-]notes[=<ref>]:: This flag is passed to the `git log` program (see linkgit:git-log[1]) that generates the patches. diff --git a/builtin/range-diff.c b/builtin/range-diff.c index 1b33ab66a7b..e41719e0f0d 100644 --- a/builtin/range-diff.c +++ b/builtin/range-diff.c @@ -21,6 +21,7 @@ int cmd_range_diff(int argc, { struct diff_options diffopt = { NULL }; struct strvec other_arg = STRVEC_INIT; + struct strvec diff_merges_arg = STRVEC_INIT; struct range_diff_options range_diff_opts = { .creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT, .diffopt = &diffopt, @@ -36,6 +37,9 @@ int cmd_range_diff(int argc, OPT_PASSTHRU_ARGV(0, "notes", &other_arg, N_("notes"), N_("passed to 'git log'"), PARSE_OPT_OPTARG), + OPT_PASSTHRU_ARGV(0, "diff-merges", &diff_merges_arg, + N_("style"), N_("passed to 'git log'"), + PARSE_OPT_OPTARG), OPT_BOOL(0, "left-only", &left_only, N_("only emit output related to the first range")), OPT_BOOL(0, "right-only", &right_only, @@ -62,6 +66,12 @@ int cmd_range_diff(int argc, if (!simple_color) diffopt.use_color = 1; + /* If `--diff-merges` was specified, imply `--merges` */ + if (diff_merges_arg.nr) { + range_diff_opts.include_merges = 1; + strvec_pushv(&other_arg, diff_merges_arg.v); + } + for (i = 0; i < argc; i++) if (!strcmp(argv[i], "--")) { dash_dash = i; @@ -155,6 +165,7 @@ int cmd_range_diff(int argc, res = show_range_diff(range1.buf, range2.buf, &range_diff_opts); strvec_clear(&other_arg); + strvec_clear(&diff_merges_arg); strbuf_release(&range1); strbuf_release(&range2); diff --git a/range-diff.c b/range-diff.c index bbb0952264b..9e59733059b 100644 --- a/range-diff.c +++ b/range-diff.c @@ -38,7 +38,8 @@ struct patch_util { * as struct object_id (will need to be free()d). */ static int read_patches(const char *range, struct string_list *list, - const struct strvec *other_arg) + const struct strvec *other_arg, + unsigned int include_merges) { struct child_process cp = CHILD_PROCESS_INIT; struct strbuf buf = STRBUF_INIT, contents = STRBUF_INIT; @@ -49,7 +50,7 @@ static int read_patches(const char *range, struct string_list *list, size_t size; int ret = -1; - strvec_pushl(&cp.args, "log", "--no-color", "-p", "--no-merges", + strvec_pushl(&cp.args, "log", "--no-color", "-p", "--reverse", "--date-order", "--decorate=no", "--no-prefix", "--submodule=short", /* @@ -64,6 +65,8 @@ static int read_patches(const char *range, struct string_list *list, "--pretty=medium", "--show-notes-by-default", NULL); + if (!include_merges) + strvec_push(&cp.args, "--no-merges"); strvec_push(&cp.args, range); if (other_arg) strvec_pushv(&cp.args, other_arg->v); @@ -96,11 +99,14 @@ static int read_patches(const char *range, struct string_list *list, } if (skip_prefix(line, "commit ", &p)) { + char *q; if (util) { string_list_append(list, buf.buf)->util = util; strbuf_reset(&buf); } CALLOC_ARRAY(util, 1); + if (include_merges && (q = strstr(p, " (from "))) + *q = '\0'; if (repo_get_oid(the_repository, p, &util->oid)) { error(_("could not parse commit '%s'"), p); FREE_AND_NULL(util); @@ -571,13 +577,14 @@ int show_range_diff(const char *range1, const char *range2, struct string_list branch1 = STRING_LIST_INIT_DUP; struct string_list branch2 = STRING_LIST_INIT_DUP; + unsigned int include_merges = range_diff_opts->include_merges; if (range_diff_opts->left_only && range_diff_opts->right_only) res = error(_("options '%s' and '%s' cannot be used together"), "--left-only", "--right-only"); - if (!res && read_patches(range1, &branch1, range_diff_opts->other_arg)) + if (!res && read_patches(range1, &branch1, range_diff_opts->other_arg, include_merges)) res = error(_("could not parse log for '%s'"), range1); - if (!res && read_patches(range2, &branch2, range_diff_opts->other_arg)) + if (!res && read_patches(range2, &branch2, range_diff_opts->other_arg, include_merges)) res = error(_("could not parse log for '%s'"), range2); if (!res) { diff --git a/range-diff.h b/range-diff.h index 2f69f6a434d..cd85000b5a0 100644 --- a/range-diff.h +++ b/range-diff.h @@ -16,6 +16,7 @@ struct range_diff_options { int creation_factor; unsigned dual_color:1; unsigned left_only:1, right_only:1; + unsigned include_merges:1; const struct diff_options *diffopt; /* may be NULL */ const struct strvec *other_arg; /* may be NULL */ }; diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh index 86010931ab6..c18a3fdab83 100755 --- a/t/t3206-range-diff.sh +++ b/t/t3206-range-diff.sh @@ -909,4 +909,20 @@ test_expect_success 'submodule changes are shown irrespective of diff.submodule' test_cmp expect actual ' +test_expect_success '--diff-merges' ' + renamed_oid=$(git rev-parse --short renamed-file) && + tree=$(git merge-tree unmodified renamed-file) && + clean=$(git commit-tree -m merge -p unmodified -p renamed-file $tree) && + clean_oid=$(git rev-parse --short $clean) && + conflict=$(git commit-tree -m merge -p unmodified -p renamed-file^ $tree) && + conflict_oid=$(git rev-parse --short $conflict) && + + git range-diff --diff-merges=1 $clean...$conflict >actual && + cat >expect <<-EOF && + 1: $renamed_oid < -: ------- s/12/B/ + 2: $clean_oid = 1: $conflict_oid merge + EOF + test_cmp expect actual +' + test_done