FIX: Voting buttons should reset on navigation (#38234)

Fixes 2 bugs introduced in the DMenu UX rewrite
(https://github.com/discourse/discourse/pull/35917):

- Vote button label cached between topics
- "Remove vote" shown on closed topics with no votes

plugins/discourse-topic-voting/assets/javascripts/discourse/components/vote-button.gjs

@@ -15,9 +15,10 @@ export default class VoteBox extends Component {
 
   @tracked hasVoted = false;
   @tracked hasSeenSuccessMenu = false;
-  topic = this.args.topic;
 
-  alreadyVoted = this.topic.user_voted;
+  get topic() {
+    return this.args.topic;
+  }
 
   get buttonContent() {
     const content = {};
@@ -58,6 +59,11 @@ export default class VoteBox extends Component {
 
   @action
   onShowMenu() {
+    if (!this.topic.user_voted) {
+      this.hasVoted = false;
+      this.hasSeenSuccessMenu = false;
+    }
+
     applyBehaviorTransformer("topic-vote-button-click", () => {
       if (!this.currentUser) {
         return this.args.showLogin();
@@ -174,14 +180,16 @@ export default class VoteBox extends Component {
                 class="btn-transparent see-votes topic-voting-menu__row-btn"
               />
             </dropdown.item>
-            <dropdown.item class="topic-voting-menu__row">
-              <DButton
-                @translatedLabel={{i18n "topic_voting.remove_vote"}}
-                @action={{this.removeVote}}
-                @icon="arrow-rotate-left"
-                class="btn-transparent remove-vote topic-voting-menu__row-btn --danger"
-              />
-            </dropdown.item>
+            {{#if this.topic.user_voted}}
+              <dropdown.item class="topic-voting-menu__row">
+                <DButton
+                  @translatedLabel={{i18n "topic_voting.remove_vote"}}
+                  @action={{this.removeVote}}
+                  @icon="arrow-rotate-left"
+                  class="btn-transparent remove-vote topic-voting-menu__row-btn --danger"
+                />
+              </dropdown.item>
+            {{/if}}
           {{/if}}
         </DropdownMenu>
       </:content>

plugins/discourse-topic-voting/spec/system/page_objects/pages/topic.rb

@@ -33,6 +33,14 @@ module TopicVotingTopic
   def click_my_votes
     find(".topic-voting-menu__votes-left").click
   end
+
+  def has_vote_button_label?(text)
+    has_css?("button.vote-button", text: text)
+  end
+
+  def has_no_remove_vote_button?
+    has_no_css?("button.remove-vote")
+  end
 end
 
 PageObjects::Pages::Topic.include(TopicVotingTopic)

plugins/discourse-topic-voting/spec/system/voting_spec.rb

@@ -63,6 +63,52 @@ RSpec.describe "Topic voting", type: :system do
     expect(topic_page.vote_count).to have_text("0")
   end
 
+  context "when navigating between voting topics" do
+    fab!(:voting_post1) { Fabricate(:post, topic: voting_topic1) }
+    fab!(:voting_post2) { Fabricate(:post, topic: voting_topic2) }
+    fab!(:voting_post3) { Fabricate(:post, topic: voting_topic3) }
+
+    before { DiscourseTopicVoting::CategorySetting.create!(category: voting_category) }
+
+    it "resets vote UI state after route transitions" do
+      voting_topic3.update!(closed: true)
+      Fabricate(:post, topic: voting_topic3, raw: "Check out #{voting_topic1.url}")
+      Fabricate(:post, topic: voting_topic1, raw: "Check out #{voting_topic2.url}")
+
+      visit("/t/#{voting_topic3.slug}/#{voting_topic3.id}")
+      expect(topic_page).to have_vote_button_label(I18n.t("js.topic_voting.voting_closed_title"))
+
+      find("a[href='#{voting_topic1.url}']").click
+      expect(topic_page).to have_vote_button_label(I18n.t("js.topic_voting.vote_title"))
+
+      topic_page.vote
+      expect(topic_page.vote_popup).to have_text(
+        I18n.t("js.topic_voting.see_votes", count: 9, max: 10),
+      )
+
+      find("a[href='#{voting_topic2.url}']").click
+      expect(topic_page).to have_vote_button_label(I18n.t("js.topic_voting.vote_title"))
+
+      topic_page.vote
+      expect(topic_page.vote_popup).to have_text(
+        I18n.t("js.topic_voting.see_votes", count: 8, max: 10),
+      )
+    end
+  end
+
+  context "when viewing a closed voting topic without having voted" do
+    before { DiscourseTopicVoting::CategorySetting.create!(category: voting_category) }
+
+    it "does not show the remove vote button" do
+      voting_topic1.update!(closed: true)
+      Fabricate(:post, topic: voting_topic1)
+
+      visit("/t/#{voting_topic1.slug}/#{voting_topic1.id}")
+      topic_page.vote
+      expect(topic_page).to have_no_remove_vote_button
+    end
+  end
+
   context "when no votes are left" do
     before do
       DiscourseTopicVoting::CategorySetting.create!(category: category1)