Merge branch 'ps/ref-peeled-tags' into jch

Some ref backend storage can hold not just the object name of an
annotated tag, but the object name of the object the tag points at.
The code to handle this information has been streamlined.

* ps/ref-peeled-tags:
  t7004: do not chdir around in the main process
  ref-filter: fix stale parsed objects
  ref-filter: parse objects on demand
  ref-filter: detect broken tags when dereferencing them
  refs: don't store peeled object IDs for invalid tags
  object: add flag to `peel_object()` to verify object type
  refs: drop infrastructure to peel via iterators
  refs: drop `current_ref_iter` hack
  builtin/show-ref: convert to use `reference_get_peeled_oid()`
  ref-filter: propagate peeled object ID
  upload-pack: convert to use `reference_get_peeled_oid()`
  refs: expose peeled object ID via the iterator
  refs: refactor reference status flags
  refs: fully reset `struct ref_iterator::ref` on iteration
  refs: introduce `.ref` field for the base iterator
  refs: introduce wrapper struct for `each_ref_fn`

7 files changed, 83 insertions, 239 deletions

diff --git a/refs/debug.c b/refs/debug.c
index c59c1728a3..f38991c02a 100644
--- a/refs/debug.c
+++ b/refs/debug.c
@@ -168,11 +168,9 @@ static int debug_ref_iterator_advance(struct ref_iterator *ref_iterator)
 		trace_printf_key(&trace_refs, "iterator_advance: (%d)\n", res);
 	else
 		trace_printf_key(&trace_refs, "iterator_advance: %s (0)\n",
-			diter->iter->refname);
+			diter->iter->ref.name);
 
-	diter->base.refname = diter->iter->refname;
-	diter->base.oid = diter->iter->oid;
-	diter->base.flags = diter->iter->flags;
+	diter->base.ref = diter->iter->ref;
 	return res;
 }
 
@@ -187,16 +185,6 @@ static int debug_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return res;
 }
 
-static int debug_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				   struct object_id *peeled)
-{
-	struct debug_ref_iterator *diter =
-		(struct debug_ref_iterator *)ref_iterator;
-	int res = diter->iter->vtable->peel(diter->iter, peeled);
-	trace_printf_key(&trace_refs, "iterator_peel: %s: %d\n", diter->iter->refname, res);
-	return res;
-}
-
 static void debug_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct debug_ref_iterator *diter =
@@ -208,7 +196,6 @@ static void debug_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable debug_ref_iterator_vtable = {
 	.advance = debug_ref_iterator_advance,
 	.seek = debug_ref_iterator_seek,
-	.peel = debug_ref_iterator_peel,
 	.release = debug_ref_iterator_release,
 };
 
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 1adc4b5182..d929f88293 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -961,26 +961,23 @@ static int files_ref_iterator_advance(struct ref_iterator *ref_iterator)
 
 	while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) {
 		if (iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&
-		    parse_worktree_ref(iter->iter0->refname, NULL, NULL,
+		    parse_worktree_ref(iter->iter0->ref.name, NULL, NULL,
 				       NULL) != REF_WORKTREE_CURRENT)
 			continue;
 
 		if ((iter->flags & DO_FOR_EACH_OMIT_DANGLING_SYMREFS) &&
-		    (iter->iter0->flags & REF_ISSYMREF) &&
-		    (iter->iter0->flags & REF_ISBROKEN))
+		    (iter->iter0->ref.flags & REF_ISSYMREF) &&
+		    (iter->iter0->ref.flags & REF_ISBROKEN))
 			continue;
 
 		if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
-		    !ref_resolves_to_object(iter->iter0->refname,
+		    !ref_resolves_to_object(iter->iter0->ref.name,
 					    iter->repo,
-					    iter->iter0->oid,
-					    iter->iter0->flags))
+					    iter->iter0->ref.oid,
+					    iter->iter0->ref.flags))
 			continue;
 
-		iter->base.refname = iter->iter0->refname;
-		iter->base.oid = iter->iter0->oid;
-		iter->base.flags = iter->iter0->flags;
-		iter->base.referent = iter->iter0->referent;
+		iter->base.ref = iter->iter0->ref;
 
 		return ITER_OK;
 	}
@@ -996,15 +993,6 @@ static int files_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return ref_iterator_seek(iter->iter0, refname, flags);
 }
 
-static int files_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				   struct object_id *peeled)
-{
-	struct files_ref_iterator *iter =
-		(struct files_ref_iterator *)ref_iterator;
-
-	return ref_iterator_peel(iter->iter0, peeled);
-}
-
 static void files_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct files_ref_iterator *iter =
@@ -1015,7 +1003,6 @@ static void files_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable files_ref_iterator_vtable = {
 	.advance = files_ref_iterator_advance,
 	.seek = files_ref_iterator_seek,
-	.peel = files_ref_iterator_peel,
 	.release = files_ref_iterator_release,
 };
 
@@ -1367,30 +1354,29 @@ static void prune_refs(struct files_ref_store *refs, struct ref_to_prune **refs_
  * Return true if the specified reference should be packed.
  */
 static int should_pack_ref(struct files_ref_store *refs,
-			   const char *refname,
-			   const struct object_id *oid, unsigned int ref_flags,
+			   const struct reference *ref,
 			   struct pack_refs_opts *opts)
 {
 	struct string_list_item *item;
 
 	/* Do not pack per-worktree refs: */
-	if (parse_worktree_ref(refname, NULL, NULL, NULL) !=
+	if (parse_worktree_ref(ref->name, NULL, NULL, NULL) !=
 	    REF_WORKTREE_SHARED)
 		return 0;
 
 	/* Do not pack symbolic refs: */
-	if (ref_flags & REF_ISSYMREF)
+	if (ref->flags & REF_ISSYMREF)
 		return 0;
 
 	/* Do not pack broken refs: */
-	if (!ref_resolves_to_object(refname, refs->base.repo, oid, ref_flags))
+	if (!ref_resolves_to_object(ref->name, refs->base.repo, ref->oid, ref->flags))
 		return 0;
 
-	if (ref_excluded(opts->exclusions, refname))
+	if (ref_excluded(opts->exclusions, ref->name))
 		return 0;
 
 	for_each_string_list_item(item, opts->includes)
-		if (!wildmatch(item->string, refname, 0))
+		if (!wildmatch(item->string, ref->name, 0))
 			return 1;
 
 	return 0;
@@ -1443,8 +1429,7 @@ static int should_pack_refs(struct files_ref_store *refs,
 	iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, 0), NULL,
 					refs->base.repo, 0);
 	while ((ret = ref_iterator_advance(iter)) == ITER_OK) {
-		if (should_pack_ref(refs, iter->refname, iter->oid,
-				    iter->flags, opts))
+		if (should_pack_ref(refs, &iter->ref, opts))
 			refcount++;
 		if (refcount >= limit) {
 			ref_iterator_free(iter);
@@ -1489,24 +1474,24 @@ static int files_pack_refs(struct ref_store *ref_store,
 		 * in the packed ref cache. If the reference should be
 		 * pruned, also add it to refs_to_prune.
 		 */
-		if (!should_pack_ref(refs, iter->refname, iter->oid, iter->flags, opts))
+		if (!should_pack_ref(refs, &iter->ref, opts))
 			continue;
 
 		/*
 		 * Add a reference creation for this reference to the
 		 * packed-refs transaction:
 		 */
-		if (ref_transaction_update(transaction, iter->refname,
-					   iter->oid, NULL, NULL, NULL,
+		if (ref_transaction_update(transaction, iter->ref.name,
+					   iter->ref.oid, NULL, NULL, NULL,
 					   REF_NO_DEREF, NULL, &err))
 			die("failure preparing to create packed reference %s: %s",
-			    iter->refname, err.buf);
+			    iter->ref.name, err.buf);
 
 		/* Schedule the loose reference for pruning if requested. */
 		if ((opts->flags & PACK_REFS_PRUNE)) {
 			struct ref_to_prune *n;
-			FLEX_ALLOC_STR(n, name, iter->refname);
-			oidcpy(&n->oid, iter->oid);
+			FLEX_ALLOC_STR(n, name, iter->ref.name);
+			oidcpy(&n->oid, iter->ref.oid);
 			n->next = refs_to_prune;
 			refs_to_prune = n;
 		}
@@ -2394,7 +2379,7 @@ static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator)
 					 REFNAME_ALLOW_ONELEVEL))
 			continue;
 
-		iter->base.refname = diter->relative_path;
+		iter->base.ref.name = diter->relative_path;
 		return ITER_OK;
 	}
 
@@ -2408,12 +2393,6 @@ static int files_reflog_iterator_seek(struct ref_iterator *ref_iterator UNUSED,
 	BUG("ref_iterator_seek() called for reflog_iterator");
 }
 
-static int files_reflog_iterator_peel(struct ref_iterator *ref_iterator UNUSED,
-				      struct object_id *peeled UNUSED)
-{
-	BUG("ref_iterator_peel() called for reflog_iterator");
-}
-
 static void files_reflog_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct files_reflog_iterator *iter =
@@ -2424,7 +2403,6 @@ static void files_reflog_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable files_reflog_iterator_vtable = {
 	.advance = files_reflog_iterator_advance,
 	.seek = files_reflog_iterator_seek,
-	.peel = files_reflog_iterator_peel,
 	.release = files_reflog_iterator_release,
 };
 
@@ -3165,14 +3143,11 @@ static int parse_and_write_reflog(struct files_ref_store *refs,
 	return 0;
 }
 
-static int ref_present(const char *refname, const char *referent UNUSED,
-		       const struct object_id *oid UNUSED,
-		       int flags UNUSED,
-		       void *cb_data)
+static int ref_present(const struct reference *ref, void *cb_data)
 {
 	struct string_list *affected_refnames = cb_data;
 
-	return string_list_has_string(affected_refnames, refname);
+	return string_list_has_string(affected_refnames, ref->name);
 }
 
 static int files_transaction_finish_initial(struct files_ref_store *refs,
diff --git a/refs/iterator.c b/refs/iterator.c
index 17ef841d8a..d79aa5ec82 100644
--- a/refs/iterator.c
+++ b/refs/iterator.c
@@ -21,12 +21,6 @@ int ref_iterator_seek(struct ref_iterator *ref_iterator, const char *refname,
 	return ref_iterator->vtable->seek(ref_iterator, refname, flags);
 }
 
-int ref_iterator_peel(struct ref_iterator *ref_iterator,
-		      struct object_id *peeled)
-{
-	return ref_iterator->vtable->peel(ref_iterator, peeled);
-}
-
 void ref_iterator_free(struct ref_iterator *ref_iterator)
 {
 	if (ref_iterator) {
@@ -41,10 +35,7 @@ void base_ref_iterator_init(struct ref_iterator *iter,
 			    struct ref_iterator_vtable *vtable)
 {
 	iter->vtable = vtable;
-	iter->refname = NULL;
-	iter->referent = NULL;
-	iter->oid = NULL;
-	iter->flags = 0;
+	memset(&iter->ref, 0, sizeof(iter->ref));
 }
 
 struct empty_ref_iterator {
@@ -63,12 +54,6 @@ static int empty_ref_iterator_seek(struct ref_iterator *ref_iterator UNUSED,
 	return 0;
 }
 
-static int empty_ref_iterator_peel(struct ref_iterator *ref_iterator UNUSED,
-				   struct object_id *peeled UNUSED)
-{
-	BUG("peel called for empty iterator");
-}
-
 static void empty_ref_iterator_release(struct ref_iterator *ref_iterator UNUSED)
 {
 }
@@ -76,7 +61,6 @@ static void empty_ref_iterator_release(struct ref_iterator *ref_iterator UNUSED)
 static struct ref_iterator_vtable empty_ref_iterator_vtable = {
 	.advance = empty_ref_iterator_advance,
 	.seek = empty_ref_iterator_seek,
-	.peel = empty_ref_iterator_peel,
 	.release = empty_ref_iterator_release,
 };
 
@@ -127,8 +111,8 @@ enum iterator_selection ref_iterator_select(struct ref_iterator *iter_worktree,
 		 * latter.
 		 */
 		if (iter_worktree) {
-			int cmp = strcmp(iter_worktree->refname,
-					 iter_common->refname);
+			int cmp = strcmp(iter_worktree->ref.name,
+					 iter_common->ref.name);
 			if (cmp < 0)
 				return ITER_SELECT_0;
 			else if (!cmp)
@@ -139,7 +123,7 @@ enum iterator_selection ref_iterator_select(struct ref_iterator *iter_worktree,
 		  * We now know that the lexicographically-next ref is a common
 		  * ref. When the common ref is a shared one we return it.
 		  */
-		if (parse_worktree_ref(iter_common->refname, NULL, NULL,
+		if (parse_worktree_ref(iter_common->ref.name, NULL, NULL,
 				       NULL) == REF_WORKTREE_SHARED)
 			return ITER_SELECT_1;
 
@@ -212,10 +196,7 @@ static int merge_ref_iterator_advance(struct ref_iterator *ref_iterator)
 		}
 
 		if (selection & ITER_YIELD_CURRENT) {
-			iter->base.referent = (*iter->current)->referent;
-			iter->base.refname = (*iter->current)->refname;
-			iter->base.oid = (*iter->current)->oid;
-			iter->base.flags = (*iter->current)->flags;
+			iter->base.ref = (*iter->current)->ref;
 			return ITER_OK;
 		}
 	}
@@ -246,18 +227,6 @@ static int merge_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return 0;
 }
 
-static int merge_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				   struct object_id *peeled)
-{
-	struct merge_ref_iterator *iter =
-		(struct merge_ref_iterator *)ref_iterator;
-
-	if (!iter->current) {
-		BUG("peel called before advance for merge iterator");
-	}
-	return ref_iterator_peel(*iter->current, peeled);
-}
-
 static void merge_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct merge_ref_iterator *iter =
@@ -269,7 +238,6 @@ static void merge_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable merge_ref_iterator_vtable = {
 	.advance = merge_ref_iterator_advance,
 	.seek = merge_ref_iterator_seek,
-	.peel = merge_ref_iterator_peel,
 	.release = merge_ref_iterator_release,
 };
 
@@ -313,7 +281,7 @@ static enum iterator_selection overlay_iterator_select(
 	else if (!front)
 		return ITER_SELECT_1;
 
-	cmp = strcmp(front->refname, back->refname);
+	cmp = strcmp(front->ref.name, back->ref.name);
 
 	if (cmp < 0)
 		return ITER_SELECT_0;
@@ -371,7 +339,7 @@ static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
 	int ok;
 
 	while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) {
-		int cmp = compare_prefix(iter->iter0->refname, iter->prefix);
+		int cmp = compare_prefix(iter->iter0->ref.name, iter->prefix);
 		if (cmp < 0)
 			continue;
 		/*
@@ -382,6 +350,8 @@ static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
 		if (cmp > 0)
 			return ITER_DONE;
 
+		iter->base.ref = iter->iter0->ref;
+
 		if (iter->trim) {
 			/*
 			 * It is nonsense to trim off characters that
@@ -392,15 +362,11 @@ static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
 			 * one character left in the refname after
 			 * trimming, report it as a bug:
 			 */
-			if (strlen(iter->iter0->refname) <= iter->trim)
+			if (strlen(iter->base.ref.name) <= iter->trim)
 				BUG("attempt to trim too many characters");
-			iter->base.refname = iter->iter0->refname + iter->trim;
-		} else {
-			iter->base.refname = iter->iter0->refname;
+			iter->base.ref.name += iter->trim;
 		}
 
-		iter->base.oid = iter->iter0->oid;
-		iter->base.flags = iter->iter0->flags;
 		return ITER_OK;
 	}
 
@@ -420,15 +386,6 @@ static int prefix_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return ref_iterator_seek(iter->iter0, refname, flags);
 }
 
-static int prefix_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				    struct object_id *peeled)
-{
-	struct prefix_ref_iterator *iter =
-		(struct prefix_ref_iterator *)ref_iterator;
-
-	return ref_iterator_peel(iter->iter0, peeled);
-}
-
 static void prefix_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct prefix_ref_iterator *iter =
@@ -440,7 +397,6 @@ static void prefix_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable prefix_ref_iterator_vtable = {
 	.advance = prefix_ref_iterator_advance,
 	.seek = prefix_ref_iterator_seek,
-	.peel = prefix_ref_iterator_peel,
 	.release = prefix_ref_iterator_release,
 };
 
@@ -466,23 +422,18 @@ struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
 	return ref_iterator;
 }
 
-struct ref_iterator *current_ref_iter = NULL;
-
 int do_for_each_ref_iterator(struct ref_iterator *iter,
 			     each_ref_fn fn, void *cb_data)
 {
 	int retval = 0, ok;
-	struct ref_iterator *old_ref_iter = current_ref_iter;
 
-	current_ref_iter = iter;
 	while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
-		retval = fn(iter->refname, iter->referent, iter->oid, iter->flags, cb_data);
+		retval = fn(&iter->ref, cb_data);
 		if (retval)
 			goto out;
 	}
 
 out:
-	current_ref_iter = old_ref_iter;
 	if (ok == ITER_ERROR)
 		retval = -1;
 	ref_iterator_free(iter);
diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index a8c22a0a7f..1ab0c50393 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -882,6 +882,7 @@ static int next_record(struct packed_ref_iterator *iter)
 {
 	const char *p, *eol;
 
+	memset(&iter->base.ref, 0, sizeof(iter->base.ref));
 	strbuf_reset(&iter->refname_buf);
 
 	/*
@@ -908,7 +909,7 @@ static int next_record(struct packed_ref_iterator *iter)
 	if (iter->pos == iter->eof)
 		return ITER_DONE;
 
-	iter->base.flags = REF_ISPACKED;
+	iter->base.ref.flags = REF_ISPACKED;
 	p = iter->pos;
 
 	if (iter->eof - p < snapshot_hexsz(iter->snapshot) + 2 ||
@@ -916,6 +917,7 @@ static int next_record(struct packed_ref_iterator *iter)
 	    !isspace(*p++))
 		die_invalid_line(iter->snapshot->refs->path,
 				 iter->pos, iter->eof - iter->pos);
+	iter->base.ref.oid = &iter->oid;
 
 	eol = memchr(p, '\n', iter->eof - p);
 	if (!eol)
@@ -923,22 +925,22 @@ static int next_record(struct packed_ref_iterator *iter)
 				      iter->pos, iter->eof - iter->pos);
 
 	strbuf_add(&iter->refname_buf, p, eol - p);
-	iter->base.refname = iter->refname_buf.buf;
+	iter->base.ref.name = iter->refname_buf.buf;
 
 	if (refname_contains_nul(&iter->refname_buf))
-		die("packed refname contains embedded NULL: %s", iter->base.refname);
+		die("packed refname contains embedded NULL: %s", iter->base.ref.name);
 
-	if (check_refname_format(iter->base.refname, REFNAME_ALLOW_ONELEVEL)) {
-		if (!refname_is_safe(iter->base.refname))
+	if (check_refname_format(iter->base.ref.name, REFNAME_ALLOW_ONELEVEL)) {
+		if (!refname_is_safe(iter->base.ref.name))
 			die("packed refname is dangerous: %s",
-			    iter->base.refname);
+			    iter->base.ref.name);
 		oidclr(&iter->oid, iter->repo->hash_algo);
-		iter->base.flags |= REF_BAD_NAME | REF_ISBROKEN;
+		iter->base.ref.flags |= REF_BAD_NAME | REF_ISBROKEN;
 	}
 	if (iter->snapshot->peeled == PEELED_FULLY ||
 	    (iter->snapshot->peeled == PEELED_TAGS &&
-	     starts_with(iter->base.refname, "refs/tags/")))
-		iter->base.flags |= REF_KNOWS_PEELED;
+	     starts_with(iter->base.ref.name, "refs/tags/")))
+		iter->base.ref.flags |= REF_KNOWS_PEELED;
 
 	iter->pos = eol + 1;
 
@@ -956,11 +958,12 @@ static int next_record(struct packed_ref_iterator *iter)
 		 * definitely know the value of *this* reference. But
 		 * we suppress it if the reference is broken:
 		 */
-		if ((iter->base.flags & REF_ISBROKEN)) {
+		if ((iter->base.ref.flags & REF_ISBROKEN)) {
 			oidclr(&iter->peeled, iter->repo->hash_algo);
-			iter->base.flags &= ~REF_KNOWS_PEELED;
+			iter->base.ref.flags &= ~REF_KNOWS_PEELED;
 		} else {
-			iter->base.flags |= REF_KNOWS_PEELED;
+			iter->base.ref.flags |= REF_KNOWS_PEELED;
+			iter->base.ref.peeled_oid = &iter->peeled;
 		}
 	} else {
 		oidclr(&iter->peeled, iter->repo->hash_algo);
@@ -976,15 +979,15 @@ static int packed_ref_iterator_advance(struct ref_iterator *ref_iterator)
 	int ok;
 
 	while ((ok = next_record(iter)) == ITER_OK) {
-		const char *refname = iter->base.refname;
+		const char *refname = iter->base.ref.name;
 		const char *prefix = iter->prefix;
 
 		if (iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&
-		    !is_per_worktree_ref(iter->base.refname))
+		    !is_per_worktree_ref(iter->base.ref.name))
 			continue;
 
 		if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
-		    !ref_resolves_to_object(iter->base.refname, iter->repo,
+		    !ref_resolves_to_object(iter->base.ref.name, iter->repo,
 					    &iter->oid, iter->flags))
 			continue;
 
@@ -1027,22 +1030,6 @@ static int packed_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return 0;
 }
 
-static int packed_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				   struct object_id *peeled)
-{
-	struct packed_ref_iterator *iter =
-		(struct packed_ref_iterator *)ref_iterator;
-
-	if ((iter->base.flags & REF_KNOWS_PEELED)) {
-		oidcpy(peeled, &iter->peeled);
-		return is_null_oid(&iter->peeled) ? -1 : 0;
-	} else if ((iter->base.flags & (REF_ISBROKEN | REF_ISSYMREF))) {
-		return -1;
-	} else {
-		return peel_object(iter->repo, &iter->oid, peeled) ? -1 : 0;
-	}
-}
-
 static void packed_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct packed_ref_iterator *iter =
@@ -1056,7 +1043,6 @@ static void packed_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable packed_ref_iterator_vtable = {
 	.advance = packed_ref_iterator_advance,
 	.seek = packed_ref_iterator_seek,
-	.peel = packed_ref_iterator_peel,
 	.release = packed_ref_iterator_release,
 };
 
@@ -1194,7 +1180,6 @@ static struct ref_iterator *packed_ref_iterator_begin(
 	iter->snapshot = snapshot;
 	acquire_snapshot(snapshot);
 	strbuf_init(&iter->refname_buf, 0);
-	iter->base.oid = &iter->oid;
 	iter->repo = ref_store->repo;
 	iter->flags = flags;
 
@@ -1436,7 +1421,7 @@ static enum ref_transaction_error write_with_updates(struct packed_ref_store *re
 			if (!iter)
 				cmp = +1;
 			else
-				cmp = strcmp(iter->refname, update->refname);
+				cmp = strcmp(iter->ref.name, update->refname);
 		}
 
 		if (!cmp) {
@@ -1459,11 +1444,11 @@ static enum ref_transaction_error write_with_updates(struct packed_ref_store *re
 					}
 
 					goto error;
-				} else if (!oideq(&update->old_oid, iter->oid)) {
+				} else if (!oideq(&update->old_oid, iter->ref.oid)) {
 					strbuf_addf(err, "cannot update ref '%s': "
 						    "is at %s but expected %s",
 						    update->refname,
-						    oid_to_hex(iter->oid),
+						    oid_to_hex(iter->ref.oid),
 						    oid_to_hex(&update->old_oid));
 					ret = REF_TRANSACTION_ERROR_INCORRECT_OLD_VALUE;
 
@@ -1523,13 +1508,8 @@ static enum ref_transaction_error write_with_updates(struct packed_ref_store *re
 
 		if (cmp < 0) {
 			/* Pass the old reference through. */
-
-			struct object_id peeled;
-			int peel_error = ref_iterator_peel(iter, &peeled);
-
-			if (write_packed_entry(out, iter->refname,
-					       iter->oid,
-					       peel_error ? NULL : &peeled))
+			if (write_packed_entry(out, iter->ref.name,
+					       iter->ref.oid, iter->ref.peeled_oid))
 				goto write_error;
 
 			if ((ok = ref_iterator_advance(iter)) != ITER_OK) {
@@ -1547,9 +1527,8 @@ static enum ref_transaction_error write_with_updates(struct packed_ref_store *re
 			i++;
 		} else {
 			struct object_id peeled;
-			int peel_error = peel_object(refs->base.repo,
-						     &update->new_oid,
-						     &peeled);
+			int peel_error = peel_object(refs->base.repo, &update->new_oid,
+						     &peeled, PEEL_OBJECT_VERIFY_OBJECT_TYPE);
 
 			if (write_packed_entry(out, update->refname,
 					       &update->new_oid,
diff --git a/refs/ref-cache.c b/refs/ref-cache.c
index e5e5df16d8..ffef01a597 100644
--- a/refs/ref-cache.c
+++ b/refs/ref-cache.c
@@ -425,10 +425,11 @@ static int cache_ref_iterator_advance(struct ref_iterator *ref_iterator)
 			level->prefix_state = entry_prefix_state;
 			level->index = -1;
 		} else {
-			iter->base.refname = entry->name;
-			iter->base.referent = entry->u.value.referent;
-			iter->base.oid = &entry->u.value.oid;
-			iter->base.flags = entry->flag;
+			memset(&iter->base.ref, 0, sizeof(iter->base.ref));
+			iter->base.ref.name = entry->name;
+			iter->base.ref.target = entry->u.value.referent;
+			iter->base.ref.oid = &entry->u.value.oid;
+			iter->base.ref.flags = entry->flag;
 			return ITER_OK;
 		}
 	}
@@ -545,14 +546,6 @@ static int cache_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return 0;
 }
 
-static int cache_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				   struct object_id *peeled)
-{
-	struct cache_ref_iterator *iter =
-		(struct cache_ref_iterator *)ref_iterator;
-	return peel_object(iter->repo, ref_iterator->oid, peeled) ? -1 : 0;
-}
-
 static void cache_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct cache_ref_iterator *iter =
@@ -564,7 +557,6 @@ static void cache_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable cache_ref_iterator_vtable = {
 	.advance = cache_ref_iterator_advance,
 	.seek = cache_ref_iterator_seek,
-	.peel = cache_ref_iterator_peel,
 	.release = cache_ref_iterator_release,
 };
 
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 4ef3bd75c6..4671517dad 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -249,10 +249,7 @@ const char *find_descendant_ref(const char *dirname,
  */
 struct ref_iterator {
 	struct ref_iterator_vtable *vtable;
-	const char *refname;
-	const char *referent;
-	const struct object_id *oid;
-	unsigned int flags;
+	struct reference ref;
 };
 
 /*
@@ -361,12 +358,6 @@ typedef int ref_iterator_seek_fn(struct ref_iterator *ref_iterator,
 				 const char *refname, unsigned int flags);
 
 /*
- * Peels the current ref, returning 0 for success or -1 for failure.
- */
-typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
-				 struct object_id *peeled);
-
-/*
  * Implementations of this function should free any resources specific
  * to the derived class.
  */
@@ -375,23 +366,9 @@ typedef void ref_iterator_release_fn(struct ref_iterator *ref_iterator);
 struct ref_iterator_vtable {
 	ref_iterator_advance_fn *advance;
 	ref_iterator_seek_fn *seek;
-	ref_iterator_peel_fn *peel;
 	ref_iterator_release_fn *release;
 };
 
-/*
- * current_ref_iter is a performance hack: when iterating over
- * references using the for_each_ref*() functions, current_ref_iter is
- * set to the reference iterator before calling the callback function.
- * If the callback function calls peel_ref(), then peel_ref() first
- * checks whether the reference to be peeled is the one referred to by
- * the iterator (it usually is) and if so, asks the iterator for the
- * peeled version of the reference if it is available. This avoids a
- * refname lookup in a common case. current_ref_iter is set to NULL
- * when the iteration is over.
- */
-extern struct ref_iterator *current_ref_iter;
-
 struct ref_store;
 
 /* refs backends */
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index eeec64798f..d46287b5ef 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -547,6 +547,7 @@ struct reftable_ref_iterator {
 	struct reftable_iterator iter;
 	struct reftable_ref_record ref;
 	struct object_id oid;
+	struct object_id peeled_oid;
 
 	char *prefix;
 	size_t prefix_len;
@@ -671,6 +672,8 @@ static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator)
 		case REFTABLE_REF_VAL2:
 			oidread(&iter->oid, iter->ref.value.val2.value,
 				refs->base.repo->hash_algo);
+			oidread(&iter->peeled_oid, iter->ref.value.val2.target_value,
+				refs->base.repo->hash_algo);
 			break;
 		case REFTABLE_REF_SYMREF:
 			referent = refs_resolve_ref_unsafe(&iter->refs->base,
@@ -704,10 +707,13 @@ static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator)
 					    &iter->oid, flags))
 				continue;
 
-		iter->base.refname = iter->ref.refname;
-		iter->base.referent = referent;
-		iter->base.oid = &iter->oid;
-		iter->base.flags = flags;
+		memset(&iter->base.ref, 0, sizeof(iter->base.ref));
+		iter->base.ref.name = iter->ref.refname;
+		iter->base.ref.target = referent;
+		iter->base.ref.oid = &iter->oid;
+		if (iter->ref.value_type == REFTABLE_REF_VAL2)
+			iter->base.ref.peeled_oid = &iter->peeled_oid;
+		iter->base.ref.flags = flags;
 
 		break;
 	}
@@ -738,21 +744,6 @@ static int reftable_ref_iterator_seek(struct ref_iterator *ref_iterator,
 	return iter->err;
 }
 
-static int reftable_ref_iterator_peel(struct ref_iterator *ref_iterator,
-				      struct object_id *peeled)
-{
-	struct reftable_ref_iterator *iter =
-		(struct reftable_ref_iterator *)ref_iterator;
-
-	if (iter->ref.value_type == REFTABLE_REF_VAL2) {
-		oidread(peeled, iter->ref.value.val2.target_value,
-			iter->refs->base.repo->hash_algo);
-		return 0;
-	}
-
-	return -1;
-}
-
 static void reftable_ref_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct reftable_ref_iterator *iter =
@@ -770,7 +761,6 @@ static void reftable_ref_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable reftable_ref_iterator_vtable = {
 	.advance = reftable_ref_iterator_advance,
 	.seek = reftable_ref_iterator_seek,
-	.peel = reftable_ref_iterator_peel,
 	.release = reftable_ref_iterator_release,
 };
 
@@ -828,7 +818,7 @@ static struct reftable_ref_iterator *ref_iterator_for_stack(struct reftable_ref_
 
 	iter = xcalloc(1, sizeof(*iter));
 	base_ref_iterator_init(&iter->base, &reftable_ref_iterator_vtable);
-	iter->base.oid = &iter->oid;
+	iter->base.ref.oid = &iter->oid;
 	iter->flags = flags;
 	iter->refs = refs;
 	iter->exclude_patterns = filter_exclude_patterns(exclude_patterns);
@@ -1642,7 +1632,8 @@ static int write_transaction_table(struct reftable_writer *writer, void *cb_data
 			ref.refname = (char *)u->refname;
 			ref.update_index = ts;
 
-			peel_error = peel_object(arg->refs->base.repo, &u->new_oid, &peeled);
+			peel_error = peel_object(arg->refs->base.repo, &u->new_oid, &peeled,
+						 PEEL_OBJECT_VERIFY_OBJECT_TYPE);
 			if (!peel_error) {
 				ref.value_type = REFTABLE_REF_VAL2;
 				memcpy(ref.value.val2.target_value, peeled.hash, GIT_MAX_RAWSZ);
@@ -2072,7 +2063,7 @@ static int reftable_reflog_iterator_advance(struct ref_iterator *ref_iterator)
 
 		strbuf_reset(&iter->last_name);
 		strbuf_addstr(&iter->last_name, iter->log.refname);
-		iter->base.refname = iter->log.refname;
+		iter->base.ref.name = iter->log.refname;
 
 		break;
 	}
@@ -2092,13 +2083,6 @@ static int reftable_reflog_iterator_seek(struct ref_iterator *ref_iterator UNUSE
 	return -1;
 }
 
-static int reftable_reflog_iterator_peel(struct ref_iterator *ref_iterator UNUSED,
-					 struct object_id *peeled UNUSED)
-{
-	BUG("reftable reflog iterator cannot be peeled");
-	return -1;
-}
-
 static void reftable_reflog_iterator_release(struct ref_iterator *ref_iterator)
 {
 	struct reftable_reflog_iterator *iter =
@@ -2111,7 +2095,6 @@ static void reftable_reflog_iterator_release(struct ref_iterator *ref_iterator)
 static struct ref_iterator_vtable reftable_reflog_iterator_vtable = {
 	.advance = reftable_reflog_iterator_advance,
 	.seek = reftable_reflog_iterator_seek,
-	.peel = reftable_reflog_iterator_peel,
 	.release = reftable_reflog_iterator_release,
 };
 
@@ -2515,7 +2498,7 @@ static int write_reflog_expiry_table(struct reftable_writer *writer, void *cb_da
 		ref.refname = (char *)arg->refname;
 		ref.update_index = ts;
 
-		if (!peel_object(arg->refs->base.repo, &arg->update_oid, &peeled)) {
+		if (!peel_object(arg->refs->base.repo, &arg->update_oid, &peeled, 0)) {
 			ref.value_type = REFTABLE_REF_VAL2;
 			memcpy(ref.value.val2.target_value, peeled.hash, GIT_MAX_RAWSZ);
 			memcpy(ref.value.val2.value, arg->update_oid.hash, GIT_MAX_RAWSZ);