FEATURE: allow moderators to bulk change ownership (#15997)

app/assets/javascripts/discourse/app/controllers/topic.js

@@ -1446,12 +1446,22 @@ export default Controller.extend(bufferedProperty("model"), {
 
   @discourseComputed(
     "currentUser.admin",
+    "currentUser.staff",
+    "siteSettings.moderators_change_post_ownership",
     "selectedPostsCount",
     "selectedPostsUsername"
   )
-  canChangeOwner(isAdmin, selectedPostsCount, selectedPostsUsername) {
+  canChangeOwner(
+    isAdmin,
+    isStaff,
+    modChangePostOwner,
+    selectedPostsCount,
+    selectedPostsUsername
+  ) {
     return (
-      isAdmin && selectedPostsCount > 0 && selectedPostsUsername !== undefined
+      (isAdmin || (modChangePostOwner && isStaff)) &&
+      selectedPostsCount > 0 &&
+      selectedPostsUsername !== undefined
     );
   },
 

app/assets/javascripts/discourse/tests/unit/controllers/topic-test.js

@@ -407,6 +407,54 @@ discourseModule("Unit | Controller | topic", function (hooks) {
     );
   });
 
+  test("modCanChangeOwner", function (assert) {
+    const currentUser = User.create({ moderator: false });
+    this.registry.register("current-user:main", currentUser, {
+      instantiate: false,
+    });
+    this.registry.injection("controller", "currentUser", "current-user:main");
+
+    let model = topicWithStream({
+      posts: [
+        { id: 1, username: "gary" },
+        { id: 2, username: "lili" },
+      ],
+      stream: [1, 2],
+    });
+    model.set("currentUser", { moderator: false });
+    const controller = this.getController("topic", {
+      model,
+      currentUser,
+      siteSettings: {
+        moderators_change_post_ownership: true,
+      },
+    });
+    const selectedPostIds = controller.get("selectedPostIds");
+
+    assert.notOk(
+      controller.get("canChangeOwner"),
+      "false when no posts are selected"
+    );
+
+    selectedPostIds.pushObject(1);
+
+    assert.notOk(controller.get("canChangeOwner"), "false when not moderator");
+
+    currentUser.set("moderator", true);
+
+    assert.ok(
+      controller.get("canChangeOwner"),
+      "true when moderator and one post is selected"
+    );
+
+    selectedPostIds.pushObject(2);
+
+    assert.notOk(
+      controller.get("canChangeOwner"),
+      "false when moderator but more than 1 user"
+    );
+  });
+
   test("canMergePosts", function (assert) {
     let model = topicWithStream({
       posts: [