drafts: Convert .data("draft-id") to a module variable.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

web/src/compose.js

@@ -132,7 +132,7 @@ export function clear_compose_box() {
     $("textarea#compose-textarea").val("").trigger("focus");
     compose_validate.check_overflow_text();
     compose_validate.clear_topic_resolved_warning();
-    $("textarea#compose-textarea").removeData("draft-id");
+    drafts.set_compose_draft_id(undefined);
     compose_ui.autosize_textarea($("textarea#compose-textarea"));
     compose_banner.clear_errors();
     compose_banner.clear_warnings();

web/src/compose_actions.ts

@@ -124,7 +124,7 @@ function clear_box(): void {
     compose_state.set_recipient_edited_manually(false);
     clear_textarea();
     compose_validate.check_overflow_text();
-    $("textarea#compose-textarea").removeData("draft-id");
+    drafts.set_compose_draft_id(undefined);
     $("textarea#compose-textarea").toggleClass("invalid", false);
     compose_ui.autosize_textarea($("textarea#compose-textarea"));
     compose_banner.clear_errors();
@@ -338,7 +338,7 @@ export function start(raw_opts: ComposeActionsStartOpts): void {
     show_compose_box(opts);
 
     if (opts.draft_id) {
-        $("textarea#compose-textarea").data("draft-id", opts.draft_id);
+        drafts.set_compose_draft_id(opts.draft_id);
     }
 
     const $clear_topic_button = $("#recipient_box_clear_topic_button");

web/src/drafts.ts

@@ -382,6 +382,12 @@ function maybe_notify(no_notify: boolean): void {
     }
 }
 
+export let compose_draft_id: string | undefined;
+
+export function set_compose_draft_id(draft_id: string | undefined): void {
+    compose_draft_id = draft_id;
+}
+
 type UpdateDraftOptions = {
     no_notify?: boolean;
     update_count?: boolean;
@@ -389,8 +395,7 @@ type UpdateDraftOptions = {
 };
 
 export function update_draft(opts: UpdateDraftOptions = {}): string | undefined {
-    const draft_id: unknown = $("textarea#compose-textarea").data("draft-id");
-    assert(draft_id === undefined || typeof draft_id === "string");
+    const draft_id = compose_draft_id;
     const old_draft = draft_id === undefined ? undefined : draft_model.getDraft(draft_id);
 
     const no_notify = opts.no_notify ?? false;
@@ -428,7 +433,7 @@ export function update_draft(opts: UpdateDraftOptions = {}): string | undefined
     // We have never saved a draft for this message, so add one.
     const update_count = opts.update_count ?? true;
     const new_draft_id = draft_model.addDraft(draft, update_count);
-    $("textarea#compose-textarea").data("draft-id", new_draft_id);
+    compose_draft_id = new_draft_id;
     maybe_notify(no_notify);
 
     return new_draft_id;

web/tests/compose_actions.test.js

@@ -46,6 +46,7 @@ mock_esm("../src/drafts", {
     update_draft: noop,
     update_compose_draft_count: noop,
     get_last_restorable_draft_based_on_compose_state: noop,
+    set_compose_draft_id: noop,
 });
 mock_esm("../src/unread_ops", {
     notify_server_message_read: noop,