From: Phillip Wood Date: Mon, 18 Sep 2023 09:53:48 GMT Subject: Re: [PATCH v5] merge-tree: add -X strategy option Message-ID: <67638fd7-ad63-4e20-87e1-bef121fef197@gmail.com> In-Reply-To: On 16/09/2023 09:37, Izzy via GitGitGadget wrote: > From: Tang Yuyi > > Add merge strategy option to produce more customizable merge result such > as automatically resolving conflicts. I think adding a merge strategy option to merge-tree is a good idea, but have you tested this with anything apart from -Xours or -Xtheirs? It looks to me like those are the only two that this patch supports. If you look at parse_merge_opt() in merge-recursive.c you will see that there are many other options. In order to support all the merge options I think this patch needs a bit of refactoring. > diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c > index 0de42aecf4b..97d0fe6c952 100644 > --- a/builtin/merge-tree.c > +++ b/builtin/merge-tree.c > static int real_merge(struct merge_tree_options *o, > @@ -439,6 +441,8 @@ static int real_merge(struct merge_tree_options *o, > > init_merge_options(&opt, the_repository); > > + opt.recursive_variant = o->merge_options.recursive_variant; > + Rather that copying across individual members I think you should initialize o->merge_options properly in cmd_merge_tree() by calling init_merge_options() and then use o->merge_options instead of "opt" in this function. That way all the strategy options will be supported. > opt.show_rename_progress = 0; > > opt.branch1 = branch1; > @@ -513,6 +517,7 @@ static int real_merge(struct merge_tree_options *o, > int cmd_merge_tree(int argc, const char **argv, const char *prefix) > { > struct merge_tree_options o = { .show_messages = -1 }; > + struct strvec xopts = STRVEC_INIT; > int expected_remaining_argc; > int original_argc; > const char *merge_base = NULL; > @@ -548,6 +553,8 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) > &merge_base, > N_("commit"), > N_("specify a merge-base for the merge")), > + OPT_STRVEC('X', "strategy-option", &xopts, N_("option=value"), > + N_("option for selected merge strategy")), > OPT_END() > }; > > @@ -556,6 +563,10 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) You should add init_merge_options(&o.merge_options); here to ensure it is properly initialized. > argc = parse_options(argc, argv, prefix, mt_options, > merge_tree_usage, PARSE_OPT_STOP_AT_NON_OPTION); This is the right place to call parse_merge_opt() but I think we should first check that the user has requested a real merge rather than a trivial merge. if (xopts.nr && o.mode == MODE_TRIVIAL) die(_("--trivial-merge is incompatible with all other options")); Otherwise if the user passes in invalid strategy option to a trivial merge they'll get an error about an invalid strategy option rather than being told --strategy-option is not supported with --trivial-merge. Ideally there would be a preparatory patch that moves the switch statement that is below the "if(o.use_stdin)" block up to this point so we'd always have set o.mode before checking if it is a trivial merge. (I think you'd to change the code slightly when it is moved to add a check for o.use_stdin) Best Wishes Phillip > + for (int x = 0; x < xopts.nr; x++) > + if (parse_merge_opt(&o.merge_options, xopts.v[x])) > + die(_("unknown strategy option: -X%s"), xopts.v[x]); > + > /* Handle --stdin */ > if (o.use_stdin) { > struct strbuf buf = STRBUF_INIT; > diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh > index 250f721795b..b2c8a43fce3 100755 > --- a/t/t4301-merge-tree-write-tree.sh > +++ b/t/t4301-merge-tree-write-tree.sh > @@ -22,6 +22,7 @@ test_expect_success setup ' > git branch side1 && > git branch side2 && > git branch side3 && > + git branch side4 && > > git checkout side1 && > test_write_lines 1 2 3 4 5 6 >numbers && > @@ -46,6 +47,13 @@ test_expect_success setup ' > test_tick && > git commit -m rename-numbers && > > + git checkout side4 && > + test_write_lines 0 1 2 3 4 5 >numbers && > + echo yo >greeting && > + git add numbers greeting && > + test_tick && > + git commit -m other-content-modifications && > + > git switch --orphan unrelated && > >something-else && > git add something-else && > @@ -97,6 +105,21 @@ test_expect_success 'Content merge and a few conflicts' ' > test_cmp expect actual > ' > > +test_expect_success 'Auto resolve conflicts by "ours" strategy option' ' > + git checkout side1^0 && > + > + # make sure merge conflict exists > + test_must_fail git merge side4 && > + git merge --abort && > + > + git merge -X ours side4 && > + git rev-parse HEAD^{tree} >expected && > + > + git merge-tree -X ours side1 side4 >actual && > + > + test_cmp expected actual > +' > + > test_expect_success 'Barf on misspelled option, with exit code other than 0 or 1' ' > # Mis-spell with single "s" instead of double "s" > test_expect_code 129 git merge-tree --write-tree --mesages FOOBAR side1 side2 2>expect && > > base-commit: ac83bc5054c2ac489166072334b4147ce6d0fccb