sequencer: rewrite update-refs as user edits todo list
An interactive rebase provides opportunities for the user to edit the todo list. The --update-refs option initializes the list with some 'update-ref <ref>' steps, but the user could add these manually. Further, the user could add or remove these steps during pauses in the interactive rebase. Add a new method, todo_list_filter_update_refs(), that scans a todo_list and compares it to the stored update-refs file. There are two actions that can happen at this point: 1. If a '<ref>/<before>/<after>' triple in the update-refs file does not have a matching 'update-ref <ref>' command in the todo-list _and_ the <after> value is the null OID, then remove that triple. Here, the user removed the 'update-ref <ref>' command before it was executed, since if it was executed then the <after> value would store the commit at that position. 2. If a 'update-ref <ref>' command in the todo-list does not have a matching '<ref>/<before>/<after>' triple in the update-refs file, then insert a new one. Store the <before> value to be the current OID pointed at by <ref>. This is handled inside of the init_update_ref_record() helper method. We can test that this works by rewriting the todo-list several times in the course of a rebase. Check that each ref is locked or unlocked for updates after each todo-list update. We can also verify that the ref update fails if a concurrent process updates one of the refs after the rebase process records the "locked" ref location. To help these tests, add a new 'set_replace_editor' helper that will replace the todo-list with an exact file. Reported-by: Phillip Wood <phillip.wood123@gmail.com> Signed-off-by: Derrick Stolee <derrickstolee@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Derrick Stolee committed
Jul 19, 2022 at 18:33 UTC
b3b1a21d1a5df87e81fa8b53c6c3cf9760ca12d4
5 files changed
+268
rebase-interactive.c
+6
index 1ff07647af..7407c59319 100644
--- a/rebase-interactive.c
+++ b/rebase-interactive.c
@@ -146,6 +146,12 @@ int edit_todo_list(struct repository *r, struct todo_list *todo_list,
return -4;
}
+ /*
+ * See if branches need to be added or removed from the update-refs
+ * file based on the new todo list.
+ */
+ todo_list_filter_update_refs(r, new_todo);
+
return 0;
}
sequencer.c
+96
index 98111e394d..20ca7b4435 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -4168,6 +4168,102 @@ cleanup:
return result;
}
+/*
+ * Parse the update-refs file for the current rebase, then remove the
+ * refs that do not appear in the todo_list (and have not had updated
+ * values stored) and add refs that are in the todo_list but not
+ * represented in the update-refs file.
+ *
+ * If there are changes to the update-refs list, then write the new state
+ * to disk.
+ */
+void todo_list_filter_update_refs(struct repository *r,
+ struct todo_list *todo_list)
+{
+ int i;
+ int updated = 0;
+ struct string_list update_refs = STRING_LIST_INIT_DUP;
+
+ sequencer_get_update_refs_state(r->gitdir, &update_refs);
+
+ /*
+ * For each item in the update_refs list, if it has no updated
+ * value and does not appear in the todo_list, then remove it
+ * from the update_refs list.
+ */
+ for (i = 0; i < update_refs.nr; i++) {
+ int j;
+ int found = 0;
+ const char *ref = update_refs.items[i].string;
+ size_t reflen = strlen(ref);
+ struct update_ref_record *rec = update_refs.items[i].util;
+
+ /* OID already stored as updated. */
+ if (!is_null_oid(&rec->after))
+ continue;
+
+ for (j = 0; !found && j < todo_list->total_nr; j++) {
+ struct todo_item *item = &todo_list->items[j];
+ const char *arg = todo_list->buf.buf + item->arg_offset;
+
+ if (item->command != TODO_UPDATE_REF)
+ continue;
+
+ if (item->arg_len != reflen ||
+ strncmp(arg, ref, reflen))
+ continue;
+
+ found = 1;
+ }
+
+ if (!found) {
+ free(update_refs.items[i].string);
+ free(update_refs.items[i].util);
+
+ update_refs.nr--;
+ MOVE_ARRAY(update_refs.items + i, update_refs.items + i + 1, update_refs.nr - i);
+
+ updated = 1;
+ i--;
+ }
+ }
+
+ /*
+ * For each todo_item, check if its ref is in the update_refs list.
+ * If not, then add it as an un-updated ref.
+ */
+ for (i = 0; i < todo_list->total_nr; i++) {
+ struct todo_item *item = &todo_list->items[i];
+ const char *arg = todo_list->buf.buf + item->arg_offset;
+ int j, found = 0;
+
+ if (item->command != TODO_UPDATE_REF)
+ continue;
+
+ for (j = 0; !found && j < update_refs.nr; j++) {
+ const char *ref = update_refs.items[j].string;
+
+ found = strlen(ref) == item->arg_len &&
+ !strncmp(ref, arg, item->arg_len);
+ }
+
+ if (!found) {
+ struct string_list_item *inserted;
+ struct strbuf argref = STRBUF_INIT;
+
+ strbuf_add(&argref, arg, item->arg_len);
+ inserted = string_list_insert(&update_refs, argref.buf);
+ inserted->util = init_update_ref_record(argref.buf);
+ strbuf_release(&argref);
+ updated = 1;
+ }
+ }
+
+ if (updated)
+ write_update_refs_state(&update_refs);
+ string_list_clear(&update_refs, 1);
+}
+
static int do_update_ref(struct repository *r, const char *refname)
{
struct string_list_item *item;
sequencer.h
+12
index 8216b62f47..563fe59933 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -133,6 +133,18 @@ void todo_list_release(struct todo_list *todo_list);
const char *todo_item_get_arg(struct todo_list *todo_list,
struct todo_item *item);
+/*
+ * Parse the update-refs file for the current rebase, then remove the
+ * refs that do not appear in the todo_list (and have not had updated
+ * values stored) and add refs that are in the todo_list but not
+ * represented in the update-refs file.
+ *
+ * If there are changes to the update-refs list, then write the new state
+ * to disk.
+ */
+void todo_list_filter_update_refs(struct repository *r,
+ struct todo_list *todo_list);
+
/* Call this to setup defaults before parsing command line options */
void sequencer_init_config(struct replay_opts *opts);
int sequencer_pick_revisions(struct repository *repo,
t/lib-rebase.sh
+15
index ec6b9b107d..b57541356b 100644
--- a/t/lib-rebase.sh
+++ b/t/lib-rebase.sh
@@ -207,3 +207,18 @@ check_reworded_commits () {
>reword-log &&
test_cmp reword-expected reword-log
}
+
+# usage: set_replace_editor <file>
+#
+# Replace the todo file with the exact contents of the given file.
+set_replace_editor () {
+ cat >script <<-\EOF &&
+ cat FILENAME >"$1"
+
+ echo 'rebase -i script after editing:'
+ cat "$1"
+ EOF
+
+ sed -e "s/FILENAME/$1/g" <script | write_script fake-editor.sh &&
+ test_set_editor "$(pwd)/fake-editor.sh"
+}
t/t3404-rebase-interactive.sh
+139
index 2fffcf5d5f..bebf9b4def 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1834,6 +1834,145 @@ test_expect_success '--update-refs updates refs correctly' '
test_cmp_rev HEAD refs/heads/no-conflict-branch
'
+test_expect_success 'respect user edits to update-ref steps' '
+ git checkout -B update-refs-break no-conflict-branch &&
+ git branch -f base HEAD~4 &&
+ git branch -f first HEAD~3 &&
+ git branch -f second HEAD~3 &&
+ git branch -f third HEAD~1 &&
+ git branch -f unseen base &&
+
+ # First, we will add breaks to the expected todo file
+ cat >fake-todo-1 <<-EOF &&
+ pick $(git rev-parse HEAD~3)
+ break
+ update-ref refs/heads/second
+ update-ref refs/heads/first
+
+ pick $(git rev-parse HEAD~2)
+ pick $(git rev-parse HEAD~1)
+ update-ref refs/heads/third
+
+ pick $(git rev-parse HEAD)
+ update-ref refs/heads/no-conflict-branch
+ EOF
+
+ # Second, we will drop some update-refs commands (and move one)
+ cat >fake-todo-2 <<-EOF &&
+ update-ref refs/heads/second
+
+ pick $(git rev-parse HEAD~2)
+ update-ref refs/heads/third
+ pick $(git rev-parse HEAD~1)
+ break
+
+ pick $(git rev-parse HEAD)
+ EOF
+
+ # Third, we will:
+ # * insert a new one (new-branch),
+ # * re-add an old one (first), and
+ # * add a second instance of a previously-stored one (second)
+ cat >fake-todo-3 <<-EOF &&
+ update-ref refs/heads/unseen
+ update-ref refs/heads/new-branch
+ pick $(git rev-parse HEAD)
+ update-ref refs/heads/first
+ update-ref refs/heads/second
+ EOF
+
+ (
+ set_replace_editor fake-todo-1 &&
+ git rebase -i --update-refs primary &&
+
+ # These branches are currently locked.
+ for b in first second third no-conflict-branch
+ do
+ test_must_fail git branch -f $b base || return 1
+ done &&
+
+ set_replace_editor fake-todo-2 &&
+ git rebase --edit-todo &&
+
+ # These branches are currently locked.
+ for b in second third
+ do
+ test_must_fail git branch -f $b base || return 1
+ done &&
+
+ # These branches are currently unlocked for checkout.
+ for b in first no-conflict-branch
+ do
+ git worktree add wt-$b $b &&
+ git worktree remove wt-$b || return 1
+ done &&
+
+ git rebase --continue &&
+
+ set_replace_editor fake-todo-3 &&
+ git rebase --edit-todo &&
+
+ # These branches are currently locked.
+ for b in second third first unseen
+ do
+ test_must_fail git branch -f $b base || return 1
+ done &&
+
+ # These branches are currently unlocked for checkout.
+ for b in no-conflict-branch
+ do
+ git worktree add wt-$b $b &&
+ git worktree remove wt-$b || return 1
+ done &&
+
+ git rebase --continue
+ ) &&
+
+ test_cmp_rev HEAD~2 refs/heads/third &&
+ test_cmp_rev HEAD~1 refs/heads/unseen &&
+ test_cmp_rev HEAD~1 refs/heads/new-branch &&
+ test_cmp_rev HEAD refs/heads/first &&
+ test_cmp_rev HEAD refs/heads/second &&
+ test_cmp_rev HEAD refs/heads/no-conflict-branch
+'
+
+test_expect_success '--update-refs: check failed ref update' '
+ git checkout -B update-refs-error no-conflict-branch &&
+ git branch -f base HEAD~4 &&
+ git branch -f first HEAD~3 &&
+ git branch -f second HEAD~2 &&
+ git branch -f third HEAD~1 &&
+
+ cat >fake-todo <<-EOF &&
+ pick $(git rev-parse HEAD~3)
+ break
+ update-ref refs/heads/first
+
+ pick $(git rev-parse HEAD~2)
+ update-ref refs/heads/second
+
+ pick $(git rev-parse HEAD~1)
+ update-ref refs/heads/third
+
+ pick $(git rev-parse HEAD)
+ update-ref refs/heads/no-conflict-branch
+ EOF
+
+ (
+ set_replace_editor fake-todo &&
+ git rebase -i --update-refs base
+ ) &&
+
+ # At this point, the values of first, second, and third are
+ # recorded in the update-refs file. We will force-update the
+ # "second" ref, but "git branch -f" will not work because of
+ # the lock in the update-refs file.
+ git rev-parse third >.git/refs/heads/second &&
+
+ git rebase --continue 2>err &&
+ grep "update_ref failed for ref '\''refs/heads/second'\''" err
+'
+
# This must be the last test in this file
test_expect_success '$EDITOR and friends are unchanged' '
test_editor_unchanged