From 134748353b2a71a34f899c9b1326ccf7ae082412 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Thu, 29 Oct 2009 23:08:31 +0100 Subject: [PATCH] Teach 'git merge' and 'git pull' the option --ff-only MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For convenience in scripts and aliases, add the option --ff-only to only allow fast-forwards (and up-to-date, despite the name). Disallow combining --ff-only and --no-ff, since they flatly contradict each other. Allow all other options to be combined with --ff-only (i.e. do not add any code to handle them specially), including the following options: * --strategy (one or more): As long as the chosen merge strategy results in up-to-date or fast-forward, the command will succeed. * --squash: I cannot imagine why anyone would want to squash commits only if fast-forward is possible, but I also see no reason why it should not be allowed. * --message: The message will always be ignored, but I see no need to explicitly disallow providing a redundant message. Acknowledgements: I did look at Yuval Kogman's earlier patch (107768 in gmane), mainly as shortcut to find my way in the code, but I did not copy anything directly. Signed-off-by: Björn Gustavsson Signed-off-by: Junio C Hamano --- Documentation/merge-options.txt | 5 ++++ builtin-merge.c | 11 ++++++++- git-pull.sh | 7 ++++-- t/t7600-merge.sh | 41 +++++++++++++++++++++++++++++++++ 4 files changed, 61 insertions(+), 3 deletions(-) diff --git a/Documentation/merge-options.txt b/Documentation/merge-options.txt index adadf8e4bf..27a9a8489c 100644 --- a/Documentation/merge-options.txt +++ b/Documentation/merge-options.txt @@ -60,6 +60,11 @@ a fast-forward, only update the branch pointer. This is the default behavior of git-merge. +--ff-only:: + Refuse to merge and exit with a non-zero status unless the + current `HEAD` is already up-to-date or the merge can be + resolved as a fast-forward. + -s :: --strategy=:: Use the given merge strategy; can be supplied more than diff --git a/builtin-merge.c b/builtin-merge.c index b6b84286b2..5e8c4b5e4b 100644 --- a/builtin-merge.c +++ b/builtin-merge.c @@ -43,6 +43,7 @@ static const char * const builtin_merge_usage[] = { static int show_diffstat = 1, option_log, squash; static int option_commit = 1, allow_fast_forward = 1; +static int fast_forward_only; static int allow_trivial = 1, have_message; static struct strbuf merge_msg; static struct commit_list *remoteheads; @@ -167,6 +168,8 @@ static struct option builtin_merge_options[] = { "perform a commit if the merge succeeds (default)"), OPT_BOOLEAN(0, "ff", &allow_fast_forward, "allow fast forward (default)"), + OPT_BOOLEAN(0, "ff-only", &fast_forward_only, + "abort if fast forward is not possible"), OPT_CALLBACK('s', "strategy", &use_strategies, "strategy", "merge strategy to use", option_parse_strategy), OPT_CALLBACK('m', "message", &merge_msg, "message", @@ -874,6 +877,9 @@ int cmd_merge(int argc, const char **argv, const char *prefix) option_commit = 0; } + if (!allow_fast_forward && fast_forward_only) + die("You cannot combine --no-ff with --ff-only."); + if (!argc) usage_with_options(builtin_merge_usage, builtin_merge_options); @@ -1040,7 +1046,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix) * only one common. */ refresh_cache(REFRESH_QUIET); - if (allow_trivial) { + if (allow_trivial && !fast_forward_only) { /* See if it is really trivial. */ git_committer_info(IDENT_ERROR_ON_NO_NAME); printf("Trying really trivial in-index merge...\n"); @@ -1079,6 +1085,9 @@ int cmd_merge(int argc, const char **argv, const char *prefix) } } + if (fast_forward_only) + die("Not possible to fast forward, aborting."); + /* We are going to make a new commit. */ git_committer_info(IDENT_ERROR_ON_NO_NAME); diff --git a/git-pull.sh b/git-pull.sh index fc78592ae0..37f3d93017 100755 --- a/git-pull.sh +++ b/git-pull.sh @@ -16,7 +16,8 @@ cd_to_toplevel test -z "$(git ls-files -u)" || die "You are in the middle of a conflicted merge." -strategy_args= diffstat= no_commit= squash= no_ff= log_arg= verbosity= +strategy_args= diffstat= no_commit= squash= no_ff= ff_only= +log_arg= verbosity= curr_branch=$(git symbolic-ref -q HEAD) curr_branch_short=$(echo "$curr_branch" | sed "s|refs/heads/||") rebase=$(git config --bool branch.$curr_branch_short.rebase) @@ -45,6 +46,8 @@ do no_ff=--ff ;; --no-ff) no_ff=--no-ff ;; + --ff-only) + ff_only=--ff-only ;; -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\ --strateg=*|--strategy=*|\ -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy) @@ -215,5 +218,5 @@ merge_name=$(git fmt-merge-msg $log_arg <"$GIT_DIR/FETCH_HEAD") || exit test true = "$rebase" && exec git-rebase $diffstat $strategy_args --onto $merge_head \ ${oldremoteref:-$merge_head} -exec git-merge $diffstat $no_commit $squash $no_ff $log_arg $strategy_args \ +exec git-merge $diffstat $no_commit $squash $no_ff $ff_only $log_arg $strategy_args \ "$merge_name" HEAD $merge_head $verbosity diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh index e5b210bc96..57f6d2bae7 100755 --- a/t/t7600-merge.sh +++ b/t/t7600-merge.sh @@ -243,6 +243,16 @@ test_expect_success 'merge c0 with c1' ' test_debug 'gitk --all' +test_expect_success 'merge c0 with c1 with --ff-only' ' + git reset --hard c0 && + git merge --ff-only c1 && + git merge --ff-only HEAD c0 c1 && + verify_merge file result.1 && + verify_head "$c1" +' + +test_debug 'gitk --all' + test_expect_success 'merge c1 with c2' ' git reset --hard c1 && test_tick && @@ -263,6 +273,14 @@ test_expect_success 'merge c1 with c2 and c3' ' test_debug 'gitk --all' +test_expect_success 'failing merges with --ff-only' ' + git reset --hard c1 && + test_tick && + test_must_fail git merge --ff-only c2 && + test_must_fail git merge --ff-only c3 && + test_must_fail git merge --ff-only c2 c3 +' + test_expect_success 'merge c0 with c1 (no-commit)' ' git reset --hard c0 && git merge --no-commit c1 && @@ -303,6 +321,17 @@ test_expect_success 'merge c0 with c1 (squash)' ' test_debug 'gitk --all' +test_expect_success 'merge c0 with c1 (squash, ff-only)' ' + git reset --hard c0 && + git merge --squash --ff-only c1 && + verify_merge file result.1 && + verify_head $c0 && + verify_no_mergehead && + verify_diff squash.1 .git/SQUASH_MSG "[OOPS] bad squash message" +' + +test_debug 'gitk --all' + test_expect_success 'merge c1 with c2 (squash)' ' git reset --hard c1 && git merge --squash c2 && @@ -314,6 +343,13 @@ test_expect_success 'merge c1 with c2 (squash)' ' test_debug 'gitk --all' +test_expect_success 'unsuccesful merge of c1 with c2 (squash, ff-only)' ' + git reset --hard c1 && + test_must_fail git merge --squash --ff-only c2 +' + +test_debug 'gitk --all' + test_expect_success 'merge c1 with c2 and c3 (squash)' ' git reset --hard c1 && git merge --squash c2 c3 && @@ -432,6 +468,11 @@ test_expect_success 'combining --squash and --no-ff is refused' ' test_must_fail git merge --no-ff --squash c1 ' +test_expect_success 'combining --ff-only and --no-ff is refused' ' + test_must_fail git merge --ff-only --no-ff c1 && + test_must_fail git merge --no-ff --ff-only c1 +' + test_expect_success 'merge c0 with c1 (ff overrides no-ff)' ' git reset --hard c0 && git config branch.master.mergeoptions "--no-ff" &&