reset: introduce ability to skip updating HEAD

In a subsequent commit we'll introduce a new caller to
`reset_working_tree()` that really only wants to update the index and
working tree, without updating any references. Introduce a new flag that
makes the caller opt in to updating HEAD and adapt all callers to set
that flag.

Note that in a previous iteration we instead introduced a flag that made
callers opt out of updating any references. This was somewhat awkward
though because we already have the `UPDATE_ORIG_HEAD` flag, so the
result was somewhat inconsistent.

Suggested-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
[jc: fixed-up a typo pointed out by Christian]
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/rebase.c b/builtin/rebase.c
index 06dcbaf5e80d38d852bd52ea11504bcb9388ccaa..10a306310cd4393cd48fbabf725b4ee11b19eafc 100644 (file)
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -607,7 +607,8 @@ static int move_to_original_branch(struct rebase_options *opts)
        strbuf_addf(&head_reflog, "%s (finish): returning to %s",
                    opts->reflog_action, opts->head_name);
        ropts.branch = opts->head_name;
-       ropts.flags = RESET_WORKING_TREE_REFS_ONLY;
+       ropts.flags = RESET_WORKING_TREE_REFS_ONLY |
+                     RESET_WORKING_TREE_UPDATE_HEAD;
        ropts.branch_msg = branch_reflog.buf;
        ropts.head_msg = head_reflog.buf;
        ret = reset_working_tree(the_repository, &ropts);
@@ -693,6 +694,7 @@ static int run_am(struct rebase_options *opts)
                ropts.oid = &opts->orig_head->object.oid;
                ropts.branch = opts->head_name;
                ropts.default_reflog_action = opts->reflog_action;
+               ropts.flags = RESET_WORKING_TREE_UPDATE_HEAD;
                reset_working_tree(the_repository, &ropts);
                error(_("\ngit encountered an error while preparing the "
                        "patches to replay\n"
@@ -862,7 +864,8 @@ static int checkout_up_to_date(struct rebase_options *options)
                    options->reflog_action, options->switch_to);
        ropts.oid = &options->orig_head->object.oid;
        ropts.branch = options->head_name;
-       ropts.flags = RESET_WORKING_TREE_RUN_POST_CHECKOUT_HOOK;
+       ropts.flags = RESET_WORKING_TREE_RUN_POST_CHECKOUT_HOOK |
+                     RESET_WORKING_TREE_UPDATE_HEAD;
        if (!ropts.branch)
                ropts.flags |=  RESET_WORKING_TREE_DETACH;
        ropts.head_msg = buf.buf;
@@ -1384,7 +1387,8 @@ int cmd_rebase(int argc,
 
                rerere_clear(the_repository, &merge_rr);
                string_list_clear(&merge_rr, 1);
-               ropts.flags = RESET_WORKING_TREE_HARD;
+               ropts.flags = RESET_WORKING_TREE_HARD |
+                             RESET_WORKING_TREE_UPDATE_HEAD;
                if (reset_working_tree(the_repository, &ropts) < 0)
                        die(_("could not discard worktree changes"));
                remove_branch_state(the_repository, 0);
@@ -1409,7 +1413,8 @@ int cmd_rebase(int argc,
                ropts.oid = &options.orig_head->object.oid;
                ropts.head_msg = head_msg.buf;
                ropts.branch = options.head_name;
-               ropts.flags = RESET_WORKING_TREE_HARD;
+               ropts.flags = RESET_WORKING_TREE_HARD |
+                             RESET_WORKING_TREE_UPDATE_HEAD;
                if (reset_working_tree(the_repository, &ropts) < 0)
                        die(_("could not move back to %s"),
                            oid_to_hex(&options.orig_head->object.oid));
@@ -1877,6 +1882,7 @@ int cmd_rebase(int argc,
        ropts.oid = &options.onto->object.oid;
        ropts.orig_head = &options.orig_head->object.oid;
        ropts.flags = RESET_WORKING_TREE_DETACH |
+                     RESET_WORKING_TREE_UPDATE_HEAD |
                      RESET_WORKING_TREE_UPDATE_ORIG_HEAD |
                      RESET_WORKING_TREE_RUN_POST_CHECKOUT_HOOK;
        ropts.head_msg = msg.buf;

diff --git a/reset.c b/reset.c
index 99f2c1b01235255a5a1c2b5b34eca2bcb967e3ce..490194380e603089dc3814841b80cf41fc6d080b 100644 (file)
--- a/reset.c
+++ b/reset.c
@@ -92,6 +92,7 @@ int reset_working_tree(struct repository *r,
        const char *switch_to_branch = opts->branch;
        unsigned reset_hard = opts->flags & RESET_WORKING_TREE_HARD;
        unsigned refs_only = opts->flags & RESET_WORKING_TREE_REFS_ONLY;
+       unsigned update_head = opts->flags & RESET_WORKING_TREE_UPDATE_HEAD;
        unsigned update_orig_head = opts->flags & RESET_WORKING_TREE_UPDATE_ORIG_HEAD;
        unsigned dry_run = opts->flags & RESET_WORKING_TREE_DRY_RUN;
        struct object_id *head = NULL, head_oid;
@@ -113,6 +114,9 @@ int reset_working_tree(struct repository *r,
        if (opts->branch_msg && !opts->branch)
                BUG("branch reflog message given without a branch");
 
+       if (update_orig_head && !update_head)
+               BUG("cannot update ORIG_HEAD without updating HEAD");
+
        if (!refs_only && !dry_run && repo_hold_locked_index(r, &lock, LOCK_REPORT_ON_ERROR) < 0) {
                ret = -1;
                goto leave_reset_head;
@@ -129,7 +133,7 @@ int reset_working_tree(struct repository *r,
                oid = &head_oid;
 
        if (refs_only) {
-               if (!dry_run)
+               if (!dry_run && update_head)
                        return update_refs(r, opts, oid, head);
                return 0;
        }
@@ -197,7 +201,8 @@ int reset_working_tree(struct repository *r,
                goto leave_reset_head;
        }
 
-       if (oid != &head_oid || update_orig_head || switch_to_branch)
+       if (update_head &&
+           (oid != &head_oid || update_orig_head || switch_to_branch))
                ret = update_refs(r, opts, oid, head);
 
 leave_reset_head:

diff --git a/reset.h b/reset.h
index 898e4a1e9504f519cee907865920ae8cbf462f5b..38b2891b53785f79d78b394bafac89c010a65863 100644 (file)
--- a/reset.h
+++ b/reset.h
@@ -19,14 +19,17 @@ enum reset_working_tree_flags {
        /* Only update refs, do not touch the worktree */
        RESET_WORKING_TREE_REFS_ONLY = (1 << 3),
 
-       /* Update ORIG_HEAD as well as HEAD */
-       RESET_WORKING_TREE_UPDATE_ORIG_HEAD = (1 << 4),
+       /* Update HEAD */
+       RESET_WORKING_TREE_UPDATE_HEAD = (1 << 4),
+
+       /* Update ORIG_HEAD */
+       RESET_WORKING_TREE_UPDATE_ORIG_HEAD = (1 << 5),
 
        /*
         * Perform a dry-run by performing the operation without updating
         * any user-visible state.
         */
-       RESET_WORKING_TREE_DRY_RUN = (1 << 5),
+       RESET_WORKING_TREE_DRY_RUN = (1 << 6),
 };
 
 struct reset_working_tree_options {

diff --git a/sequencer.c b/sequencer.c
index 4efe831178e464ac209df8d5053d94ab5bdc8374..e905b1b2d97b54f407c87f11f6aefd9fec5d3d52 100644 (file)
--- a/sequencer.c
+++ b/sequencer.c
@@ -4678,7 +4678,8 @@ static void create_autostash_internal(struct repository *r,
            has_uncommitted_changes(r, 1)) {
                struct child_process stash = CHILD_PROCESS_INIT;
                struct reset_working_tree_options ropts = {
-                       .flags = RESET_WORKING_TREE_HARD,
+                       .flags = RESET_WORKING_TREE_HARD |
+                                RESET_WORKING_TREE_UPDATE_HEAD,
                };
                struct object_id oid;
 
@@ -4873,6 +4874,7 @@ static int checkout_onto(struct repository *r, struct replay_opts *opts,
                .oid = onto,
                .orig_head = orig_head,
                .flags = RESET_WORKING_TREE_DETACH |
+                        RESET_WORKING_TREE_UPDATE_HEAD |
                         RESET_WORKING_TREE_UPDATE_ORIG_HEAD |
                         RESET_WORKING_TREE_RUN_POST_CHECKOUT_HOOK,
                .head_msg = reflog_message(opts, "start", "checkout %s",