fast-import: introduce "feature notes" command

[thirdparty/git.git] / builtin-checkout.c

diff --git a/builtin-checkout.c b/builtin-checkout.c
index 67229fc21607ceb51c34d77c4ef5682d96f1e909..c5ab7835e1fe260b9ec61f216bf198011eabf6f7 100644 (file)
--- a/builtin-checkout.c
+++ b/builtin-checkout.c
@@ -17,6 +17,7 @@
 #include "blob.h"
 #include "xdiff-interface.h"
 #include "ll-merge.h"
+#include "resolve-undo.h"
 
 static const char * const checkout_usage[] = {
        "git checkout [options] <branch>",
@@ -234,6 +235,10 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
        if (report_path_error(ps_matched, pathspec, 0))
                return 1;
 
+       /* "checkout -m path" to recreate conflicted state */
+       if (opts->merge)
+               unmerge_cache(pathspec);
+
        /* Any unmerged paths? */
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
@@ -370,6 +375,7 @@ static int merge_working_tree(struct checkout_opts *opts,
        if (read_cache_preload(NULL) < 0)
                return error("corrupt index file");
 
+       resolve_undo_clear();
        if (opts->force) {
                ret = reset_tree(new->commit->tree, opts, 1);
                if (ret)
@@ -482,6 +488,20 @@ static void report_tracking(struct branch_info *new)
        strbuf_release(&sb);
 }
 
+static void detach_advice(const char *old_path, const char *new_name)
+{
+       const char fmt[] =
+       "Note: checking out '%s'.\n\n"
+       "You are in 'detached HEAD' state. You can look around, make experimental\n"
+       "changes and commit them, and you can discard any commits you make in this\n"
+       "state without impacting any branches by performing another checkout.\n\n"
+       "If you want to create a new branch to retain commits you create, you may\n"
+       "do so (now or later) by using -b with the checkout command again. Example:\n\n"
+       "  git checkout -b new_branch_name\n\n";
+
+       fprintf(stderr, fmt, new_name);
+}
+
 static void update_refs_for_switch(struct checkout_opts *opts,
                                   struct branch_info *old,
                                   struct branch_info *new)
@@ -516,8 +536,8 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
                           REF_NODEREF, DIE_ON_ERR);
                if (!opts->quiet) {
-                       if (old->path)
-                               fprintf(stderr, "Note: moving to '%s' which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n  git checkout -b <new_branch_name>\n", new->name);
+                       if (old->path && advice_detached_head)
+                               detach_advice(old->path, new->name);
                        describe_detached_head("HEAD is now at", new->commit);
                }
        }
@@ -696,7 +716,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
         * case 3: git checkout <something> [<paths>]
         *
         *   With no paths, if <something> is a commit, that is to
-        *   switch to the branch or detach HEAD at it.
+        *   switch to the branch or detach HEAD at it.  As a special case,
+        *   if <something> is A...B (missing A or B means HEAD but you can
+        *   omit at most one side), and if there is a unique merge base
+        *   between A and B, A...B names that merge base.
         *
         *   With no paths, if <something> is _not_ a commit, no -t nor -b
         *   was given, and there is a tracking branch whose name is
@@ -722,7 +745,7 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                if (!strcmp(arg, "-"))
                        arg = "@{-1}";
 
-               if (get_sha1(arg, rev)) {
+               if (get_sha1_mb(arg, rev)) {
                        if (has_dash_dash)          /* case (1) */
                                die("invalid reference: %s", arg);
                        if (!patch_mode &&
@@ -749,8 +772,10 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                new.name = arg;
                if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
                        setup_branch_path(&new);
-                       if (resolve_ref(new.path, rev, 1, NULL))
-                               new.commit = lookup_commit_reference(rev);
+
+                       if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
+                           resolve_ref(new.path, rev, 1, NULL))
+                               ;
                        else
                                new.path = NULL;
                        parse_commit(new.commit);