refactor: Create `compose_textarea` and extracted related handlers from `ui.js`.

Created the new `compose_textarea` and moved event handlers for `#compose_textarea`
from `ui` to this new module so that it is now responsible for initializing event handlers
for compose_textarea instead of `ui` module.

tools/test-js-with-node

@@ -67,6 +67,7 @@ EXEMPT_FILES = make_set(
         "web/src/compose_fade.js",
         "web/src/compose_recipient.js",
         "web/src/compose_state.js",
+        "web/src/compose_textarea.js",
         "web/src/compose_ui.js",
         "web/src/compose_validate.js",
         "web/src/composebox_typeahead.js",

web/src/compose_textarea.js

@@ -0,0 +1,25 @@
+import $ from "jquery";
+
+// Save the compose content cursor position and restore when we
+// shift-tab back in (see hotkey.js).
+let saved_compose_cursor = 0;
+
+function set_compose_textarea_handlers() {
+    $("#compose-textarea").on("blur", function () {
+        saved_compose_cursor = $(this).caret();
+    });
+
+    // on the end of the modified-message fade in, remove the fade-in-message class.
+    const animationEnd = "webkitAnimationEnd oanimationend msAnimationEnd animationend";
+    $("body").on(animationEnd, ".fade-in-message", function () {
+        $(this).removeClass("fade-in-message");
+    });
+}
+
+export function restore_compose_cursor() {
+    $("#compose-textarea").trigger("focus").caret(saved_compose_cursor);
+}
+
+export function initialize() {
+    set_compose_textarea_handlers();
+}

web/src/hotkey.js

@@ -8,6 +8,7 @@ import * as compose_actions from "./compose_actions";
 import * as compose_banner from "./compose_banner";
 import * as compose_recipient from "./compose_recipient";
 import * as compose_state from "./compose_state";
+import * as compose_textarea from "./compose_textarea";
 import * as condense from "./condense";
 import * as copy_and_paste from "./copy_and_paste";
 import * as deprecated_feature_notice from "./deprecated_feature_notice";
@@ -44,7 +45,6 @@ import * as stream_list from "./stream_list";
 import * as stream_popover from "./stream_popover";
 import * as stream_settings_ui from "./stream_settings_ui";
 import * as topic_zoom from "./topic_zoom";
-import * as ui from "./ui";
 import * as unread_ops from "./unread_ops";
 import {user_settings} from "./user_settings";
 
@@ -557,7 +557,7 @@ export function process_shift_tab_key() {
     if ($("#compose-send-button").is(":focus")) {
         // Shift-Tab: go back to content textarea and restore
         // cursor position.
-        ui.restore_compose_cursor();
+        compose_textarea.restore_compose_cursor();
         return true;
     }
 

web/src/ui.js

@@ -43,27 +43,3 @@ export function reset_scrollbar($element) {
         element.scrollTop = 0;
     }
 }
-
-// Save the compose content cursor position and restore when we
-// shift-tab back in (see hotkey.js).
-let saved_compose_cursor = 0;
-
-export function set_compose_textarea_handlers() {
-    $("#compose-textarea").on("blur", function () {
-        saved_compose_cursor = $(this).caret();
-    });
-
-    // on the end of the modified-message fade in, remove the fade-in-message class.
-    const animationEnd = "webkitAnimationEnd oanimationend msAnimationEnd animationend";
-    $("body").on(animationEnd, ".fade-in-message", function () {
-        $(this).removeClass("fade-in-message");
-    });
-}
-
-export function restore_compose_cursor() {
-    $("#compose-textarea").trigger("focus").caret(saved_compose_cursor);
-}
-
-export function initialize() {
-    set_compose_textarea_handlers();
-}

web/src/ui_init.js

@@ -24,6 +24,7 @@ import * as compose from "./compose";
 import * as compose_closed_ui from "./compose_closed_ui";
 import * as compose_pm_pill from "./compose_pm_pill";
 import * as compose_recipient from "./compose_recipient";
+import * as compose_textarea from "./compose_textarea";
 import * as composebox_typeahead from "./composebox_typeahead";
 import * as condense from "./condense";
 import * as copy_and_paste from "./copy_and_paste";
@@ -668,6 +669,7 @@ export function initialize_everything() {
     realm_playground.initialize(page_params.realm_playgrounds, generated_pygments_data);
     compose.initialize();
     composebox_typeahead.initialize(); // Must happen after compose.initialize()
+    compose_textarea.initialize();
     search.initialize();
     tutorial.initialize();
     notifications.initialize();
@@ -694,7 +696,6 @@ export function initialize_everything() {
     drafts.initialize();
     sent_messages.initialize();
     hotspots.initialize();
-    ui.initialize();
     typing.initialize();
     starred_messages.initialize();
     user_status_ui.initialize();