merge-base --octopus to mimic show-branch --merge-base

diff --git a/builtin/checkout.c b/builtin/checkout.c
index acefaaf41a4e26e45225f6d228734c93c8f2b23c..1994be92c66257da18c31502bda605be170fd092 100644 (file)
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -33,6 +33,7 @@ struct checkout_opts {
        int writeout_error;
 
        const char *new_branch;
+       const char *new_orphan_branch;
        int new_branch_log;
        enum branch_track track;
 };
@@ -149,7 +150,7 @@ static int checkout_merged(int pos, struct checkout *state)
        read_mmblob(&ours, active_cache[pos+1]->sha1);
        read_mmblob(&theirs, active_cache[pos+2]->sha1);
 
-       status = ll_merge(&result_buf, path, &ancestor,
+       status = ll_merge(&result_buf, path, &ancestor, "base",
                          &ours, "ours", &theirs, "theirs", 0);
        free(ancestor.ptr);
        free(ours.ptr);
@@ -439,6 +440,7 @@ static int merge_working_tree(struct checkout_opts *opts,
                        ret = reset_tree(new->commit->tree, opts, 1);
                        if (ret)
                                return ret;
+                       o.ancestor = old->name;
                        o.branch1 = new->name;
                        o.branch2 = "local";
                        merge_trees(&o, new->commit->tree, work,
@@ -491,8 +493,26 @@ static void update_refs_for_switch(struct checkout_opts *opts,
        struct strbuf msg = STRBUF_INIT;
        const char *old_desc;
        if (opts->new_branch) {
-               create_branch(old->name, opts->new_branch, new->name, 0,
-                             opts->new_branch_log, opts->track);
+               if (opts->new_orphan_branch) {
+                       if (opts->new_branch_log && !log_all_ref_updates) {
+                               int temp;
+                               char log_file[PATH_MAX];
+                               char *ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
+
+                               temp = log_all_ref_updates;
+                               log_all_ref_updates = 1;
+                               if (log_ref_setup(ref_name, log_file, sizeof(log_file))) {
+                                       fprintf(stderr, "Can not do reflog for '%s'\n",
+                                           opts->new_orphan_branch);
+                                       log_all_ref_updates = temp;
+                                       return;
+                               }
+                               log_all_ref_updates = temp;
+                       }
+               }
+               else
+                       create_branch(old->name, opts->new_branch, new->name, 0,
+                                     opts->new_branch_log, opts->track);
                new->name = opts->new_branch;
                setup_branch_path(new);
        }
@@ -514,6 +534,14 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                                        opts->new_branch ? " a new" : "",
                                        new->name);
                }
+               if (old->path && old->name) {
+                       char log_file[PATH_MAX], ref_file[PATH_MAX];
+
+                       git_snpath(log_file, sizeof(log_file), "logs/%s", old->path);
+                       git_snpath(ref_file, sizeof(ref_file), "%s", old->path);
+                       if (!file_exists(ref_file) && file_exists(log_file))
+                               remove_path(log_file);
+               }
        } else if (strcmp(new->name, "HEAD")) {
                update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
                           REF_NODEREF, DIE_ON_ERR);
@@ -608,7 +636,8 @@ static int check_tracking_name(const char *refname, const unsigned char *sha1,
 
 static const char *unique_tracking_name(const char *name)
 {
-       struct tracking_name_data cb_data = { name, NULL, 1 };
+       struct tracking_name_data cb_data = { NULL, NULL, 1 };
+       cb_data.name = name;
        for_each_ref(check_tracking_name, &cb_data);
        if (cb_data.unique)
                return cb_data.remote;
@@ -632,6 +661,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
                OPT_SET_INT('t', "track",  &opts.track, "track",
                        BRANCH_TRACK_EXPLICIT),
+               OPT_STRING(0, "orphan", &opts.new_orphan_branch, "new branch", "new unparented branch"),
                OPT_SET_INT('2', "ours", &opts.writeout_stage, "stage",
                            2),
                OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
@@ -677,6 +707,14 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                opts.new_branch = argv0 + 1;
        }
 
+       if (opts.new_orphan_branch) {
+               if (opts.new_branch)
+                       die("--orphan and -b are mutually exclusive");
+               if (opts.track > 0)
+                       die("--orphan cannot be used with -t");
+               opts.new_branch = opts.new_orphan_branch;
+       }
+
        if (conflict_style) {
                opts.merge = 1; /* implied */
                git_xmerge_config("merge.conflictstyle", conflict_style, NULL);