[PATCH v6 2/4] git-cherry-pick: Add keep-redundant-commits option
- From
Neil Horman <nhorman@tuxdriver.com>
- Date
- Apr 17, 2012, 18:20 UTC
- Message-ID
- <1334686809-17634-3-git-send-email-nhorman@tuxdriver.com>
- In-Reply-To
- <1334686809-17634-1-git-send-email-nhorman@tuxdriver.com>
The git-cherry-pick --allow-empty command by default only preserves empty commits that were originally empty, i.e only those commits for which <commit>^{tree} and <commit>^^{tree} are equal. By default commits which are non-empty, but were made empty by the inclusion of a prior commit on the current history are filtered out. This option allows us to override that behavior and include redundant commits as empty commits in the change history.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com> --- Documentation/git-cherry-pick.txt | 12 ++++- builtin/revert.c | 8 +++- sequencer.c | 97 ++++++++++++++++++++++++++++++++----- sequencer.h | 1 + 4 files changed, 103 insertions(+), 15 deletions(-)
diff --git a/Documentation/git-cherry-pick.txt b/Documentation/git-cherry-pick.txt index 730237a..0c004e9 100644 --- a/Documentation/git-cherry-pick.txt +++ b/Documentation/git-cherry-pick.txt @@ -110,7 +110,17 @@ effect to your index in a row. behavior, allowing empty commits to be preserved automatically in a cherry-pick. Note that when "--ff" is in effect, empty commits that meet the "fast-forward" requirement will be kept - even without this option. + even without this option. Note also, that use of this option only + keeps commits that were initially empty (i.e. the commit recorded the + same tree as its parent). Commits which are made empty due to a + previous commit are ignored. To force the inclusion of those commits + use `--keep-redundant-commits`. + +--keep-redundant-commits:: + If a commit being cherry picked duplicates a commit already in the + current history, it will result in an empty changeset. By default these + redundant commits are ignored. This option overrides that behavior and + creates an empty commit object. Implies `--allow-empty`. --strategy=<strategy>:: Use the given merge strategy. Should only be used once. diff --git a/builtin/revert.c b/builtin/revert.c index 06b00e6..f135502 100644 --- a/builtin/revert.c +++ b/builtin/revert.c @@ -115,13 +115,15 @@ static void parse_args(int argc, const char **argv, struct replay_opts *opts) OPT_END(), OPT_END(), OPT_END(), + OPT_END(), }; if (opts->action == REPLAY_PICK) { struct option cp_extra[] = { OPT_BOOLEAN('x', NULL, &opts->record_origin, "append commit name"), OPT_BOOLEAN(0, "ff", &opts->allow_ff, "allow fast-forward"), - OPT_BOOLEAN(0, "allow-empty", &opts->allow_empty, "preserve empty commits"), + OPT_BOOLEAN(0, "allow-empty", &opts->allow_empty, "preserve initially empty commits"), + OPT_BOOLEAN(0, "keep-redundant-commits", &opts->keep_redundant_commits, "keep redundant, empty commits"), OPT_END(), }; if (parse_options_concat(options, ARRAY_SIZE(options), cp_extra)) @@ -139,6 +141,10 @@ static void parse_args(int argc, const char **argv, struct replay_opts *opts) "--abort", rollback, NULL); + /* keep_if_made_empty implies allow_empty */ + if (opts->keep_redundant_commits) + opts->allow_empty = 1; + /* Set the subcommand */ if (remove_state) opts->subcommand = REPLAY_REMOVE_STATE; diff --git a/sequencer.c b/sequencer.c index 71929ba..acc9c6d 100644 --- a/sequencer.c +++ b/sequencer.c @@ -13,6 +13,7 @@ #include "rerere.h" #include "merge-recursive.h" #include "refs.h" +#include "argv-array.h" #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION" @@ -251,6 +252,30 @@ static int do_recursive_merge(struct commit *base, struct commit *next, return !clean; } +static int is_index_unchanged() +{ + unsigned char head_sha1[20]; + struct commit *head_commit; + + if (!resolve_ref_unsafe("HEAD", head_sha1, 1, NULL)) + return error(_("Could not resolve HEAD commit\n")); + + head_commit = lookup_commit(head_sha1); + if (!head_commit || parse_commit(head_commit)) + return error(_("could not parse commit %s\n"), + sha1_to_hex(head_commit->object.sha1)); + + if (!active_cache_tree) + active_cache_tree = cache_tree(); + + if (!cache_tree_fully_valid(active_cache_tree)) + if (cache_tree_update(active_cache_tree, active_cache, + active_nr, 0)) + return error(_("Unable to update cache tree\n")); + + return !hashcmp(active_cache_tree->sha1, head_commit->tree->object.sha1); +} + /* * If we are cherry-pick, and if the merge did not result in * hand-editing, we will hit this commit and inherit the original @@ -258,26 +283,67 @@ static int do_recursive_merge(struct commit *base, struct commit *next, * If we are revert, or if our cherry-pick results in a hand merge, * we had better say that the current user is responsible for that. */ -static int run_git_commit(const char *defmsg, struct replay_opts *opts) +static int run_git_commit(const char *defmsg, struct replay_opts *opts, int empty) { - /* 7 is max possible length of our args array including NULL */ - const char *args[7]; - int i = 0; + struct argv_array array; + int rc; + int index_unchanged = is_index_unchanged(); + + /* + * if index_unchanged is < 0, then we encountered an error + * trying to parse HEAD or the active_cache_tree, so bail out + */ + if (index_unchanged < 0) + return index_unchanged; + + if (!empty && !opts->keep_redundant_commits && index_unchanged) + /* + * The head tree and the index match + * meaning the commit is empty. Since it wasn't created + * empty (based on the previous test), we can conclude + * the commit has been made redundant. Since we don't + * want to keep redundant commits, we can just return + * here, skipping this commit + */ + return 0; + + argv_array_init(&array); + argv_array_push(&array, "commit"); + argv_array_push(&array, "-n"); - args[i++] = "commit"; - args[i++] = "-n"; if (opts->signoff) - args[i++] = "-s"; + argv_array_push(&array, "-s"); if (!opts->edit) { - args[i++] = "-F"; - args[i++] = defmsg; + argv_array_push(&array, "-F"); + argv_array_push(&array, defmsg); } + if (opts->allow_empty) - args[i++] = "--allow-empty"; + argv_array_push(&array, "--allow-empty"); + + rc = run_command_v_opt(array.argv, RUN_GIT_CMD); + argv_array_clear(&array); + return rc; +} - args[i] = NULL; +static int is_original_commit_empty(struct commit *commit) +{ + const unsigned char *ptree_sha1; - return run_command_v_opt(args, RUN_GIT_CMD); + if (parse_commit(commit)) + return error(_("Could not parse commit %s\n"), + sha1_to_hex(commit->object.sha1)); + if (commit->parents) { + struct commit *parent = commit->parents->item; + if (parse_commit(parent)) + return error(_("Could not parse parent commit %s\n"), + sha1_to_hex(parent->object.sha1)); + ptree_sha1 = parent->tree->object.sha1; + } else { + ptree_sha1 = EMPTY_TREE_SHA1_BIN; /* commit is root */ + } + + return !hashcmp(ptree_sha1, commit->tree->object.sha1); } static int do_pick_commit(struct commit *commit, struct replay_opts *opts) @@ -289,6 +355,7 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts) char *defmsg = NULL; struct strbuf msgbuf = STRBUF_INIT; int res; + int empty_commit; if (opts->no_commit) { /* @@ -414,6 +481,10 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts) free_commit_list(remotes); } + empty_commit = is_original_commit_empty(commit); + if (empty_commit < 0) + return empty_commit; + /* * If the merge was clean or if it failed due to conflict, we write * CHERRY_PICK_HEAD for the subsequent invocation of commit to use. @@ -435,7 +506,7 @@ static int do_pick_commit(struct commit *commit, struct replay_opts *opts) rerere(opts->allow_rerere_auto); } else { if (!opts->no_commit) - res = run_git_commit(defmsg, opts); + res = run_git_commit(defmsg, opts, empty_commit); } free_message(&msg); diff --git a/sequencer.h b/sequencer.h index e2cd725..aa5f17c 100644 --- a/sequencer.h +++ b/sequencer.h @@ -30,6 +30,7 @@ struct replay_opts { int allow_ff; int allow_rerere_auto; int allow_empty; + int keep_redundant_commits; int mainline;
-- 1.7.7.6