From: Dominique Martinet Date: Wed, 31 Dec 2025 03:42:17 GMT Subject: [RFC PATCH] builtin/format-patch: print a warning for skipped merge commits? Message-ID: <20251231034217.2498648-1-asmadeus@codewreck.org> Git format-patch historically silently ignores merge commits, because a merge commit simply cannot be fully described by a simple patch. This can be surprising for users, especially when coupled with newer merge-heavy workflows such as encouraged by jj: trying to generate a patch from a jj commit that was a git merge with "content" will not generate anything, without any message. This RFC patch illustrates how we could easily print a warning, but perhaps the warning would only make sense if no other commit has been formatted? I don't think it hurts all that much to print all the time but I can see it being annoying in some use-cases, so it'd likely deserve a config knob if we inconditionally print that... Also perhaps pretty-printing the merge commit a bit better like printing the subject... Please let me know what you think would make sense here and I'll send a more proper patch (tests..) Thanks! Reported-by: Julien Moutinho Signed-off-by: Dominique Martinet --- builtin/log.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/builtin/log.c b/builtin/log.c index d4cf9c59c81a..b21274461cd3 100644 --- a/builtin/log.c +++ b/builtin/log.c @@ -2044,7 +2044,6 @@ int cmd_format_patch(int argc, rev.expand_tabs_in_log_default = 0; rev.verbose_header = 1; rev.diff = 1; - rev.max_parents = 1; rev.diffopt.flags.recursive = 1; rev.diffopt.no_free = 1; memset(&s_r_opt, 0, sizeof(s_r_opt)); @@ -2274,6 +2273,11 @@ int cmd_format_patch(int argc, die(_("revision walk setup failed")); rev.boundary = 1; while ((commit = get_revision(&rev)) != NULL) { + if (commit->parents->next) { + warning(_("skipped merge commit %s"), + oid_to_hex(&commit->object.oid)); + continue; + } if (commit->object.flags & BOUNDARY) { boundary_count++; origin = (boundary_count == 1) ? commit : NULL; -- 2.52.0