Fixes toggle discussion button not expanding collapsed discussions

Discussions were being toggled by jquery DOM querying them and toggling
visibility but in vue, only the open discussions will be in the DOM
Fix includes:
 - Adds a getter to the store to get the expanded discussions
 - Adds an action to collapse a discussion
 - When the user clicks the button, all data needed is now accessible
   through a getter and we can dispatch an action to toggle the discussion
   within the state, instead of showing/hiding with jQuery
 - Removes hardcoded properties

Resolves #48237

6 files changed, 89 insertions, 6 deletions

diff --git a/app/assets/javascripts/diffs/components/diff_file_header.vue b/app/assets/javascripts/diffs/components/diff_file_header.vue
index 1957698c6c1..ac4f37512ec 100644
--- a/app/assets/javascripts/diffs/components/diff_file_header.vue
+++ b/app/assets/javascripts/diffs/components/diff_file_header.vue
@@ -1,5 +1,6 @@
 <script>
 import _ from 'underscore';
+import { mapActions, mapGetters } from 'vuex';
 import ClipboardButton from '~/vue_shared/components/clipboard_button.vue';
 import Icon from '~/vue_shared/components/icon.vue';
 import FileIcon from '~/vue_shared/components/file_icon.vue';
@@ -54,6 +55,10 @@ export default {
     };
   },
   computed: {
+    ...mapGetters('diffs', ['diffHasExpandedDiscussions']),
+    hasExpandedDiscussions() {
+      return this.diffHasExpandedDiscussions(this.diffFile);
+    },
     icon() {
       if (this.diffFile.submodule) {
         return 'archive';
@@ -88,9 +93,6 @@ export default {
     collapseIcon() {
       return this.expanded ? 'chevron-down' : 'chevron-right';
     },
-    isDiscussionsExpanded() {
-      return this.discussionsExpanded && this.expanded;
-    },
     viewFileButtonText() {
       const truncatedContentSha = _.escape(truncateSha(this.diffFile.contentSha));
       return sprintf(
@@ -113,6 +115,7 @@ export default {
     },
   },
   methods: {
+    ...mapActions('diffs', ['toggleFileDiscussions']),
     handleToggle(e, checkTarget) {
       if (
         !checkTarget ||
@@ -125,6 +128,9 @@ export default {
     showForkMessage() {
       this.$emit('showForkMessage');
     },
+    handleToggleDiscussions(){
+      this.toggleFileDiscussions(this.diffFile);
+    },
   },
 };
 </script>
@@ -216,9 +222,10 @@ export default {
         v-if="diffFile.blob && diffFile.blob.readableText"
       >
         <button
-          :class="{ active: isDiscussionsExpanded }"
+          :class="{ active: hasExpandedDiscussions }"
           :title="s__('MergeRequests|Toggle comments for this file')"
-          class="btn js-toggle-diff-comments"
+          @click="handleToggleDiscussions"
+          class="btn"
           type="button"
         >
           <icon name="comment" />
diff --git a/app/assets/javascripts/diffs/store/actions.js b/app/assets/javascripts/diffs/store/actions.js
index 5e0fd5109bb..2e6092d7e87 100644
--- a/app/assets/javascripts/diffs/store/actions.js
+++ b/app/assets/javascripts/diffs/store/actions.js
@@ -82,6 +82,36 @@ export const expandAllFiles = ({ commit }) => {
   commit(types.EXPAND_ALL_FILES);
 };
 
+/**
+ * Toggles the file discussions after user clicked on the toggle discussions button.
+ *
+ * Gets the discussions for the provided diff.
+ *
+ * If all discussions are expanded, it will collapse all of them
+ * If all discussions are collapsed, it will expand all of them
+ * If some discussions are open and others closed, it will expand the closed ones.
+ *
+ * @param {Object} diff
+ */
+export const toggleFileDiscussions = ({ getters, dispatch }, diff) => {
+  const discussions = getters.getDiffFileDiscussions(diff);
+
+  const shouldCloseAll = getters.diffHasAllExpandedDiscussions(diff);
+  const shouldExpandAll = getters.diffHasAllCollpasedDiscussions(diff);
+
+  discussions.forEach(discussion => {
+    const data = { discussionId: discussion.id };
+
+    if (shouldCloseAll) {
+      dispatch('collapseDiscussion', data, { root: true });
+    } else if (shouldExpandAll) {
+      dispatch('expandDiscussion', data, { root: true });
+    } else if (!shouldCloseAll && !shouldExpandAll && !discussion.expanded) {
+      dispatch('expandDiscussion', data, { root: true });
+    }
+  });
+};
+
 export default {
   setBaseConfig,
   fetchDiffFiles,
@@ -92,4 +122,5 @@ export default {
   loadMoreLines,
   loadCollapsedDiff,
   expandAllFiles,
+  toggleFileDiscussions,
 };
diff --git a/app/assets/javascripts/diffs/store/getters.js b/app/assets/javascripts/diffs/store/getters.js
index f3c2d7427e7..9a8d27d0b04 100644
--- a/app/assets/javascripts/diffs/store/getters.js
+++ b/app/assets/javascripts/diffs/store/getters.js
@@ -1,3 +1,4 @@
+import _ from 'underscore';
 import { PARALLEL_DIFF_VIEW_TYPE, INLINE_DIFF_VIEW_TYPE } from '../constants';
 
 export const isParallelView = state => state.diffViewType === PARALLEL_DIFF_VIEW_TYPE;
@@ -8,5 +9,38 @@ export const areAllFilesCollapsed = state => state.diffFiles.every(file => file.
 
 export const commitId = state => (state.commit && state.commit.id ? state.commit.id : null);
 
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
+/**
+ * Checks if the diff has all discussions expanded
+ * @param {Object} diff
+ * @returns {Boolean}
+ */
+export const diffHasAllExpandedDiscussions = (state, getters) => diff => {
+  const discussions = getters.getDiffFileDiscussions(diff);
+
+  return (discussions.length && discussions.every(discussion => discussion.expanded)) || false;
+};
+
+/**
+ * Checks if the diff has all discussions collpased
+ * @param {Object} diff
+ * @returns {Boolean}
+ */
+export const diffHasAllCollpasedDiscussions = (state, getters) => diff => {
+  const discussions = getters.getDiffFileDiscussions(diff);
+
+  return (discussions.length && discussions.every(discussion => !discussion.expanded)) || false;
+};
+
+/**
+ * Returns an array with the discussions of the given diff
+ * @param {Object} diff
+ * @returns {Array}
+ */
+export const getDiffFileDiscussions = (state, getters, rootState, rootGetters) => diff =>
+  rootGetters.discussions.filter(
+    discussion =>
+      discussion.diff_discussion && _.isEqual(discussion.diff_file.file_hash, diff.fileHash),
+  ) || [];
+
+// prevent babel-plugin-rewire from generating an invalid default during karma∂ tests
 export default () => {};
diff --git a/app/assets/javascripts/notes/stores/actions.js b/app/assets/javascripts/notes/stores/actions.js
index b2bf86eea56..3eefbe11c37 100644
--- a/app/assets/javascripts/notes/stores/actions.js
+++ b/app/assets/javascripts/notes/stores/actions.js
@@ -15,6 +15,8 @@ let eTagPoll;
 
 export const expandDiscussion = ({ commit }, data) => commit(types.EXPAND_DISCUSSION, data);
 
+export const collapseDiscussion = ({ commit }, data) => commit(types.COLLAPSE_DISCUSSION, data);
+
 export const setNotesData = ({ commit }, data) => commit(types.SET_NOTES_DATA, data);
 
 export const setNoteableData = ({ commit }, data) => commit(types.SET_NOTEABLE_DATA, data);
diff --git a/app/assets/javascripts/notes/stores/mutation_types.js b/app/assets/javascripts/notes/stores/mutation_types.js
index a25098fbc06..6c1ffdf266b 100644
--- a/app/assets/javascripts/notes/stores/mutation_types.js
+++ b/app/assets/javascripts/notes/stores/mutation_types.js
@@ -17,6 +17,10 @@ export const UPDATE_DISCUSSION = 'UPDATE_DISCUSSION';
 export const SET_DISCUSSION_DIFF_LINES = 'SET_DISCUSSION_DIFF_LINES';
 export const SET_NOTES_FETCHED_STATE = 'SET_NOTES_FETCHED_STATE';
 
+// DISCUSSION
+
+export const COLLAPSE_DISCUSSION = 'COLLAPSE_DISCUSSION';
+
 // Issue
 export const CLOSE_ISSUE = 'CLOSE_ISSUE';
 export const REOPEN_ISSUE = 'REOPEN_ISSUE';
diff --git a/app/assets/javascripts/notes/stores/mutations.js b/app/assets/javascripts/notes/stores/mutations.js
index a1849269010..ab6a95e2601 100644
--- a/app/assets/javascripts/notes/stores/mutations.js
+++ b/app/assets/javascripts/notes/stores/mutations.js
@@ -58,6 +58,11 @@ export default {
     discussion.expanded = true;
   },
 
+  [types.COLLAPSE_DISCUSSION](state, { discussionId }) {
+    const discussion = utils.findNoteObjectById(state.discussions, discussionId);
+    discussion.expanded = false;
+  },
+
   [types.REMOVE_PLACEHOLDER_NOTES](state) {
     const { discussions } = state;