Removes unified diff components feature flag

Removes the unified diff component feature flag
as well as removes the components that are no longer used.

Changelog: added

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/268039

app/assets/javascripts/diffs/components/diff_content.vue

 <script>
 import { GlLoadingIcon } from '@gitlab/ui';
 import { mapActions, mapGetters, mapState } from 'vuex';
-import { mapInline, mapParallel } from 'ee_else_ce/diffs/components/diff_row_utils';
+import { mapParallel } from 'ee_else_ce/diffs/components/diff_row_utils';
 import DiffFileDrafts from '~/batch_comments/components/diff_file_drafts.vue';
 import draftCommentsMixin from '~/diffs/mixins/draft_comments';
 import { diffViewerModes } from '~/ide/constants';
@@ -9,7 +9,6 @@ import diffLineNoteFormMixin from '~/notes/mixins/diff_line_note_form';
 import DiffViewer from '~/vue_shared/components/diff_viewer/diff_viewer.vue';
 import NoPreviewViewer from '~/vue_shared/components/diff_viewer/viewers/no_preview.vue';
 import NotDiffableViewer from '~/vue_shared/components/diff_viewer/viewers/not_diffable.vue';
-import glFeatureFlagsMixin from '~/vue_shared/mixins/gl_feature_flags_mixin';
 import NoteForm from '../../notes/components/note_form.vue';
 import eventHub from '../../notes/event_hub';
 import userAvatarLink from '../../vue_shared/components/user_avatar/user_avatar_link.vue';
@@ -18,14 +17,10 @@ import { getDiffMode } from '../store/utils';
 import DiffDiscussions from './diff_discussions.vue';
 import DiffView from './diff_view.vue';
 import ImageDiffOverlay from './image_diff_overlay.vue';
-import InlineDiffView from './inline_diff_view.vue';
-import ParallelDiffView from './parallel_diff_view.vue';
 
 export default {
   components: {
     GlLoadingIcon,
-    InlineDiffView,
-    ParallelDiffView,
     DiffView,
     DiffViewer,
     NoteForm,
@@ -36,7 +31,7 @@ export default {
     userAvatarLink,
     DiffFileDrafts,
   },
-  mixins: [diffLineNoteFormMixin, draftCommentsMixin, glFeatureFlagsMixin()],
+  mixins: [diffLineNoteFormMixin, draftCommentsMixin],
   props: {
     diffFile: {
       type: Object,
@@ -52,7 +47,6 @@ export default {
     ...mapState('diffs', ['projectPath']),
     ...mapGetters('diffs', [
       'isInlineView',
-      'isParallelView',
       'getCommentFormForDiffFile',
       'diffLines',
       'fileLineCodequality',
@@ -86,15 +80,8 @@ export default {
       return this.getUserData;
     },
     mappedLines() {
-      if (this.glFeatures.unifiedDiffComponents) {
-        return this.diffLines(this.diffFile, true).map(mapParallel(this)) || [];
-      }
-
-      // TODO: Everything below this line can be deleted when unifiedDiffComponents FF is removed
-      if (this.isInlineView) {
-        return this.diffFile.highlighted_diff_lines.map(mapInline(this));
-      }
-      return this.diffLines(this.diffFile).map(mapParallel(this));
+      // TODO: Do this data generation when we recieve a response to save a computed property being created
+      return this.diffLines(this.diffFile).map(mapParallel(this)) || [];
     },
   },
   updated() {
@@ -126,7 +113,7 @@ export default {
 <template>
   <div class="diff-content">
     <div class="diff-viewer">
-      <template v-if="isTextFile && glFeatures.unifiedDiffComponents">
+      <template v-if="isTextFile">
         <diff-view
           :diff-file="diffFile"
           :diff-lines="mappedLines"
@@ -135,21 +122,6 @@ export default {
         />
         <gl-loading-icon v-if="diffFile.renderingLines" size="md" class="mt-3" />
       </template>
-      <template v-else-if="isTextFile">
-        <inline-diff-view
-          v-if="isInlineView"
-          :diff-file="diffFile"
-          :diff-lines="mappedLines"
-          :help-page-path="helpPagePath"
-        />
-        <parallel-diff-view
-          v-else-if="isParallelView"
-          :diff-file="diffFile"
-          :diff-lines="mappedLines"
-          :help-page-path="helpPagePath"
-        />
-        <gl-loading-icon v-if="diffFile.renderingLines" size="md" class="mt-3" />
-      </template>
       <not-diffable-viewer v-else-if="notDiffable" />
       <no-preview-viewer v-else-if="noPreview" />
       <diff-viewer

app/assets/javascripts/diffs/components/diff_line_note_form.vue

@@ -106,10 +106,7 @@ export default {
       };
       const getDiffLines = () => {
         if (this.diffViewType === PARALLEL_DIFF_VIEW_TYPE) {
-          return this.diffLines(this.diffFile, this.glFeatures.unifiedDiffComponents).reduce(
-            combineSides,
-            [],
-          );
+          return this.diffLines(this.diffFile).reduce(combineSides, []);
         }
 
         return this.diffFile[INLINE_DIFF_LINES_KEY];

app/assets/javascripts/diffs/components/diff_row.vue

@@ -210,6 +210,7 @@ export default {
 <template>
   <div :class="classNameMap" class="diff-grid-row diff-tr line_holder">
     <div
+      :id="line.left && line.left.line_code"
       data-testid="left-side"
       class="diff-grid-left left-side"
       v-bind="interopLeftAttributes"
@@ -292,7 +293,6 @@ export default {
           />
         </div>
         <div
-          :id="line.left.line_code"
           :key="line.left.line_code"
           :class="[parallelViewLeftLineType, { parallel: !inline }]"
           class="diff-td line_content with-coverage left-side"
@@ -333,6 +333,7 @@ export default {
     </div>
     <div
       v-if="!inline"
+      :id="line.right && line.right.line_code"
       data-testid="right-side"
       class="diff-grid-right right-side"
       v-bind="interopRightAttributes"
@@ -407,7 +408,6 @@ export default {
           />
         </div>
         <div
-          :id="line.right.line_code"
           :key="line.right.rich_text"
           :class="[
             line.right.type,

app/assets/javascripts/diffs/components/diff_row_utils.js

@@ -139,24 +139,3 @@ export const mapParallel = (content) => (line) => {
     commentRowClasses: hasDiscussions(left) || hasDiscussions(right) ? '' : 'js-temp-notes-holder',
   };
 };
-
-// TODO: Delete this function when unifiedDiffComponents FF is removed
-export const mapInline = (content) => (line) => {
-  // Discussions/Comments
-  const renderCommentRow = line.hasForm || (line.discussions?.length && line.discussionsExpanded);
-
-  return {
-    ...line,
-    renderDiscussion: Boolean(line.discussions?.length),
-    isMatchLine: isMatchLine(line.type),
-    commentRowClasses: line.discussions?.length ? '' : 'js-temp-notes-holder',
-    renderCommentRow,
-    hasDraft: content.shouldRenderDraftRow(content.diffFile.file_hash, line),
-    hasCommentForm: line.hasForm,
-    isMetaLine: isMetaLine(line.type),
-    isContextLine: isContextLine(line.type),
-    hasDiscussions: hasDiscussions(line),
-    lineHref: lineHref(line),
-    lineCode: lineCode(line),
-  };
-};

app/assets/javascripts/diffs/components/inline_diff_table_row.vue

-<script>
-import { GlTooltipDirective, GlIcon, GlSafeHtmlDirective as SafeHtml } from '@gitlab/ui';
-import { mapActions, mapGetters, mapState } from 'vuex';
-import { CONTEXT_LINE_CLASS_NAME } from '../constants';
-import { getInteropInlineAttributes } from '../utils/interoperability';
-import DiffGutterAvatars from './diff_gutter_avatars.vue';
-import {
-  isHighlighted,
-  shouldShowCommentButton,
-  shouldRenderCommentButton,
-  classNameMapCell,
-  addCommentTooltip,
-} from './diff_row_utils';
-
-export default {
-  components: {
-    DiffGutterAvatars,
-    GlIcon,
-  },
-  directives: {
-    GlTooltip: GlTooltipDirective,
-    SafeHtml,
-  },
-  props: {
-    fileHash: {
-      type: String,
-      required: true,
-    },
-    filePath: {
-      type: String,
-      required: true,
-    },
-    line: {
-      type: Object,
-      required: true,
-    },
-    isBottom: {
-      type: Boolean,
-      required: false,
-      default: false,
-    },
-    isCommented: {
-      type: Boolean,
-      required: false,
-      default: false,
-    },
-  },
-  data() {
-    return {
-      isHover: false,
-    };
-  },
-  computed: {
-    ...mapGetters(['isLoggedIn']),
-    ...mapGetters('diffs', ['fileLineCoverage']),
-    ...mapState({
-      isHighlighted(state) {
-        return isHighlighted(state, this.line, this.isCommented);
-      },
-    }),
-    classNameMap() {
-      return [
-        this.line.type,
-        {
-          [CONTEXT_LINE_CLASS_NAME]: this.line.isContextLine,
-        },
-      ];
-    },
-    inlineRowId() {
-      return this.line.line_code || `${this.fileHash}_${this.line.old_line}_${this.line.new_line}`;
-    },
-    coverageState() {
-      return this.fileLineCoverage(this.filePath, this.line.new_line);
-    },
-    classNameMapCell() {
-      return classNameMapCell({
-        line: this.line,
-        hll: this.isHighlighted,
-        isLoggedIn: this.isLoggedIn,
-        isHover: this.isHover,
-      });
-    },
-    addCommentTooltip() {
-      return addCommentTooltip(this.line);
-    },
-    shouldRenderCommentButton() {
-      return shouldRenderCommentButton(this.isLoggedIn, true);
-    },
-    shouldShowCommentButton() {
-      return shouldShowCommentButton(
-        this.isHover,
-        this.line.isContextLine,
-        this.line.isMetaLine,
-        this.line.hasDiscussions,
-      );
-    },
-    shouldShowAvatarsOnGutter() {
-      return this.line.hasDiscussions;
-    },
-    interopAttrs() {
-      return getInteropInlineAttributes(this.line);
-    },
-  },
-  mounted() {
-    this.scrollToLineIfNeededInline(this.line);
-  },
-  methods: {
-    ...mapActions('diffs', [
-      'scrollToLineIfNeededInline',
-      'showCommentForm',
-      'setHighlightedRow',
-      'toggleLineDiscussions',
-    ]),
-    handleMouseMove(e) {
-      // To show the comment icon on the gutter we need to know if we hover the line.
-      // Current table structure doesn't allow us to do this with CSS in both of the diff view types
-      this.isHover = e.type === 'mouseover';
-    },
-    handleCommentButton() {
-      this.showCommentForm({ lineCode: this.line.line_code, fileHash: this.fileHash });
-    },
-  },
-};
-</script>
-
-<template>
-  <tr
-    :id="inlineRowId"
-    :class="classNameMap"
-    class="line_holder"
-    v-bind="interopAttrs"
-    @mouseover="handleMouseMove"
-    @mouseout="handleMouseMove"
-  >
-    <td ref="oldTd" class="diff-line-num old_line" :class="classNameMapCell">
-      <span
-        v-if="shouldRenderCommentButton"
-        ref="addNoteTooltip"
-        v-gl-tooltip
-        class="add-diff-note tooltip-wrapper"
-        :title="addCommentTooltip"
-      >
-        <button
-          v-show="shouldShowCommentButton"
-          ref="addDiffNoteButton"
-          type="button"
-          class="add-diff-note note-button js-add-diff-note-button"
-          :disabled="line.commentsDisabled"
-          :aria-label="addCommentTooltip"
-          @click="handleCommentButton"
-        >
-          <gl-icon :size="12" name="comment" />
-        </button>
-      </span>
-      <a
-        v-if="line.old_line"
-        ref="lineNumberRefOld"
-        :data-linenumber="line.old_line"
-        :href="line.lineHref"
-        @click="setHighlightedRow(line.lineCode)"
-      >
-      </a>
-      <diff-gutter-avatars
-        v-if="shouldShowAvatarsOnGutter"
-        :discussions="line.discussions"
-        :discussions-expanded="line.discussionsExpanded"
-        @toggleLineDiscussions="
-          toggleLineDiscussions({
-            lineCode: line.lineCode,
-            fileHash,
-            expanded: !line.discussionsExpanded,
-          })
-        "
-      />
-    </td>
-    <td ref="newTd" class="diff-line-num new_line" :class="classNameMapCell">
-      <a
-        v-if="line.new_line"
-        ref="lineNumberRefNew"
-        :data-linenumber="line.new_line"
-        :href="line.lineHref"
-        @click="setHighlightedRow(line.lineCode)"
-      >
-      </a>
-    </td>
-    <td
-      v-gl-tooltip.hover
-      :title="coverageState.text"
-      :class="[line.type, coverageState.class, { hll: isHighlighted }]"
-      class="line-coverage"
-    ></td>
-    <td
-      :key="line.line_code"
-      v-safe-html="line.rich_text"
-      :class="[
-        line.type,
-        {
-          hll: isHighlighted,
-        },
-      ]"
-      class="line_content with-coverage"
-    ></td>
-  </tr>
-</template>

app/assets/javascripts/diffs/components/inline_diff_view.vue

-<script>
-import { mapGetters, mapState } from 'vuex';
-import DraftNote from '~/batch_comments/components/draft_note.vue';
-import draftCommentsMixin from '~/diffs/mixins/draft_comments';
-import { getCommentedLines } from '~/notes/components/multiline_comment_utils';
-import glFeatureFlagsMixin from '~/vue_shared/mixins/gl_feature_flags_mixin';
-import DiffCommentCell from './diff_comment_cell.vue';
-import DiffExpansionCell from './diff_expansion_cell.vue';
-import inlineDiffTableRow from './inline_diff_table_row.vue';
-
-export default {
-  components: {
-    DiffCommentCell,
-    inlineDiffTableRow,
-    DraftNote,
-    DiffExpansionCell,
-  },
-  mixins: [draftCommentsMixin, glFeatureFlagsMixin()],
-  props: {
-    diffFile: {
-      type: Object,
-      required: true,
-    },
-    diffLines: {
-      type: Array,
-      required: true,
-    },
-    helpPagePath: {
-      type: String,
-      required: false,
-      default: '',
-    },
-  },
-  computed: {
-    ...mapGetters('diffs', ['commitId']),
-    ...mapState({
-      selectedCommentPosition: ({ notes }) => notes.selectedCommentPosition,
-      selectedCommentPositionHover: ({ notes }) => notes.selectedCommentPositionHover,
-    }),
-    diffLinesLength() {
-      return this.diffLines.length;
-    },
-    commentedLines() {
-      return getCommentedLines(
-        this.selectedCommentPosition || this.selectedCommentPositionHover,
-        this.diffLines,
-      );
-    },
-  },
-  userColorScheme: window.gon.user_color_scheme,
-};
-</script>
-
-<template>
-  <table
-    :class="$options.userColorScheme"
-    :data-commit-id="commitId"
-    class="code diff-wrap-lines js-syntax-highlight text-file js-diff-inline-view"
-  >
-    <colgroup>
-      <col style="width: 50px" />
-      <col style="width: 50px" />
-      <col style="width: 8px" />
-      <col />
-    </colgroup>
-    <tbody>
-      <template v-for="(line, index) in diffLines">
-        <tr v-if="line.isMatchLine" :key="`expand-${index}`" class="line_expansion match">
-          <td colspan="4" class="text-center gl-font-regular">
-            <diff-expansion-cell
-              :file-hash="diffFile.file_hash"
-              :context-lines-path="diffFile.context_lines_path"
-              :line="line"
-              :is-top="index === 0"
-              :is-bottom="index + 1 === diffLinesLength"
-            />
-          </td>
-        </tr>
-        <inline-diff-table-row
-          v-if="!line.isMatchLine"
-          :key="`${line.line_code || index}`"
-          :file-hash="diffFile.file_hash"
-          :file-path="diffFile.file_path"
-          :line="line"
-          :is-bottom="index + 1 === diffLinesLength"
-          :is-commented="index >= commentedLines.startLine && index <= commentedLines.endLine"
-        />
-        <tr
-          v-if="line.renderCommentRow"
-          :key="`icr-${line.line_code || index}`"
-          :class="line.commentRowClasses"
-          class="notes_holder"
-        >
-          <td class="notes-content" colspan="4">
-            <diff-comment-cell
-              :diff-file-hash="diffFile.file_hash"
-              :line="line"
-              :help-page-path="helpPagePath"
-              :has-draft="line.hasDraft"
-            />
-          </td>
-        </tr>
-        <tr v-if="line.hasDraft" :key="`draft_${index}`" class="notes_holder js-temp-notes-holder">
-          <td class="notes-content" colspan="4">
-            <div class="content">
-              <draft-note
-                :draft="draftForLine(diffFile.file_hash, line)"
-                :diff-file="diffFile"
-                :line="line"
-              />
-            </div>
-          </td>
-        </tr>
-      </template>
-    </tbody>
-  </table>
-</template>

app/assets/javascripts/diffs/components/parallel_diff_table_row.vue

-<script>
-import { GlTooltipDirective, GlIcon, GlSafeHtmlDirective as SafeHtml } from '@gitlab/ui';
-import $ from 'jquery';
-import { mapActions, mapGetters, mapState } from 'vuex';
-import { CONTEXT_LINE_CLASS_NAME, PARALLEL_DIFF_VIEW_TYPE } from '../constants';
-import {
-  getInteropOldSideAttributes,
-  getInteropNewSideAttributes,
-} from '../utils/interoperability';
-import DiffGutterAvatars from './diff_gutter_avatars.vue';
-import * as utils from './diff_row_utils';
-
-export default {
-  components: {
-    GlIcon,
-    DiffGutterAvatars,
-  },
-  directives: {
-    GlTooltip: GlTooltipDirective,
-    SafeHtml,
-  },
-  props: {
-    fileHash: {
-      type: String,
-      required: true,
-    },
-    filePath: {
-      type: String,
-      required: true,
-    },
-    line: {
-      type: Object,
-      required: true,
-    },
-    isBottom: {
-      type: Boolean,
-      required: false,
-      default: false,
-    },
-    isCommented: {
-      type: Boolean,
-      required: false,
-      default: false,
-    },
-  },
-  data() {
-    return {
-      isLeftHover: false,
-      isRightHover: false,
-      isCommentButtonRendered: false,
-    };
-  },
-  computed: {
-    ...mapGetters('diffs', ['fileLineCoverage']),
-    ...mapGetters(['isLoggedIn']),
-    ...mapState({
-      isHighlighted(state) {
-        const line = this.line.left?.line_code ? this.line.left : this.line.right;
-        return utils.isHighlighted(state, line, this.isCommented);
-      },
-    }),
-    classNameMap() {
-      return {
-        [CONTEXT_LINE_CLASS_NAME]: this.line.isContextLineLeft,
-        [PARALLEL_DIFF_VIEW_TYPE]: true,
-      };
-    },
-    parallelViewLeftLineType() {
-      return utils.parallelViewLeftLineType(this.line, this.isHighlighted);
-    },
-    coverageState() {
-      return this.fileLineCoverage(this.filePath, this.line.right.new_line);
-    },
-    classNameMapCellLeft() {
-      return utils.classNameMapCell({
-        line: this.line.left,
-        hll: this.isHighlighted,
-        isLoggedIn: this.isLoggedIn,
-        isHover: this.isLeftHover,
-      });
-    },
-    classNameMapCellRight() {
-      return utils.classNameMapCell({
-        line: this.line.right,
-        hll: this.isHighlighted,
-        isLoggedIn: this.isLoggedIn,
-        isHover: this.isRightHover,
-      });
-    },
-    addCommentTooltipLeft() {
-      return utils.addCommentTooltip(this.line.left);
-    },
-    addCommentTooltipRight() {
-      return utils.addCommentTooltip(this.line.right);
-    },
-    shouldRenderCommentButton() {
-      return utils.shouldRenderCommentButton(this.isLoggedIn, this.isCommentButtonRendered);
-    },
-    shouldShowCommentButtonLeft() {
-      return utils.shouldShowCommentButton(
-        this.isLeftHover,
-        this.line.isContextLineLeft,
-        this.line.isMetaLineLeft,
-        this.line.hasDiscussionsLeft,
-      );
-    },
-    shouldShowCommentButtonRight() {
-      return utils.shouldShowCommentButton(
-        this.isRightHover,
-        this.line.isContextLineRight,
-        this.line.isMetaLineRight,
-        this.line.hasDiscussionsRight,
-      );
-    },
-    interopLeftAttributes() {
-      return getInteropOldSideAttributes(this.line.left);
-    },
-    interopRightAttributes() {
-      return getInteropNewSideAttributes(this.line.right);
-    },
-  },
-  mounted() {
-    this.scrollToLineIfNeededParallel(this.line);
-    this.unwatchShouldShowCommentButton = this.$watch(
-      (vm) => [vm.shouldShowCommentButtonLeft, vm.shouldShowCommentButtonRight].join(),
-      (newVal) => {
-        if (newVal) {
-          this.isCommentButtonRendered = true;
-          this.unwatchShouldShowCommentButton();
-        }
-      },
-    );
-  },
-  beforeDestroy() {
-    this.unwatchShouldShowCommentButton();
-  },
-  methods: {
-    ...mapActions('diffs', [
-      'scrollToLineIfNeededParallel',
-      'showCommentForm',
-      'setHighlightedRow',
-      'toggleLineDiscussions',
-    ]),
-    handleMouseMove(e) {
-      const isHover = e.type === 'mouseover';
-      const hoveringCell = e.target.closest('td');
-      const allCellsInHoveringRow = Array.from(e.currentTarget.children);
-      const hoverIndex = allCellsInHoveringRow.indexOf(hoveringCell);
-
-      if (hoverIndex >= 3) {
-        this.isRightHover = isHover;
-      } else {
-        this.isLeftHover = isHover;
-      }
-    },
-    // Prevent text selecting on both sides of parallel diff view
-    // Backport of the same code from legacy diff notes.
-    handleParallelLineMouseDown(e) {
-      const line = $(e.currentTarget);
-      const table = line.closest('table');
-
-      table.removeClass('left-side-selected right-side-selected');
-      const [lineClass] = ['left-side', 'right-side'].filter((name) => line.hasClass(name));
-
-      if (lineClass) {
-        table.addClass(`${lineClass}-selected`);
-      }
-    },
-    handleCommentButton(line) {
-      this.showCommentForm({ lineCode: line.line_code, fileHash: this.fileHash });
-    },
-  },
-};
-</script>
-
-<template>
-  <tr
-    :class="classNameMap"
-    class="line_holder"
-    @mouseover="handleMouseMove"
-    @mouseout="handleMouseMove"
-  >
-    <template v-if="line.left && !line.isMatchLineLeft">
-      <td ref="oldTd" :class="classNameMapCellLeft" class="diff-line-num old_line">
-        <span
-          v-if="shouldRenderCommentButton"
-          ref="addNoteTooltipLeft"
-          v-gl-tooltip
-          class="add-diff-note tooltip-wrapper"
-          :title="addCommentTooltipLeft"
-        >
-          <button
-            v-show="shouldShowCommentButtonLeft"
-            ref="addDiffNoteButtonLeft"
-            type="button"
-            class="add-diff-note note-button js-add-diff-note-button"
-            :disabled="line.left.commentsDisabled"
-            :aria-label="addCommentTooltipLeft"
-            @click="handleCommentButton(line.left)"
-          >
-            <gl-icon :size="12" name="comment" />
-          </button>
-        </span>
-        <a
-          v-if="line.left.old_line"
-          ref="lineNumberRefOld"
-          :data-linenumber="line.left.old_line"
-          :href="line.lineHrefOld"
-          @click="setHighlightedRow(line.lineCode)"
-        >
-        </a>
-        <diff-gutter-avatars
-          v-if="line.hasDiscussionsLeft"
-          :discussions="line.left.discussions"
-          :discussions-expanded="line.left.discussionsExpanded"
-          @toggleLineDiscussions="
-            toggleLineDiscussions({
-              lineCode: line.left.line_code,
-              fileHash,
-              expanded: !line.left.discussionsExpanded,
-            })
-          "
-        />
-      </td>
-      <td :class="parallelViewLeftLineType" class="line-coverage left-side"></td>
-      <td
-        :id="line.left.line_code"
-        :key="line.left.line_code"
-        v-safe-html="line.left.rich_text"
-        :class="parallelViewLeftLineType"
-        v-bind="interopLeftAttributes"
-        class="line_content with-coverage parallel left-side"
-        @mousedown="handleParallelLineMouseDown"
-      ></td>
-    </template>
-    <template v-else>
-      <td class="diff-line-num old_line empty-cell"></td>
-      <td class="line-coverage left-side empty-cell"></td>
-      <td class="line_content with-coverage parallel left-side empty-cell"></td>
-    </template>
-    <template v-if="line.right && !line.isMatchLineRight">
-      <td ref="newTd" :class="classNameMapCellRight" class="diff-line-num new_line">
-        <span
-          v-if="shouldRenderCommentButton"
-          ref="addNoteTooltipRight"
-          v-gl-tooltip
-          class="add-diff-note tooltip-wrapper"
-          :title="addCommentTooltipRight"
-        >
-          <button
-            v-show="shouldShowCommentButtonRight"
-            ref="addDiffNoteButtonRight"
-            type="button"
-            class="add-diff-note note-button js-add-diff-note-button"
-            :disabled="line.right.commentsDisabled"
-            :aria-label="addCommentTooltipRight"
-            @click="handleCommentButton(line.right)"
-          >
-            <gl-icon :size="12" name="comment" />
-          </button>
-        </span>
-        <a
-          v-if="line.right.new_line"
-          ref="lineNumberRefNew"
-          :data-linenumber="line.right.new_line"
-          :href="line.lineHrefNew"
-          @click="setHighlightedRow(line.lineCode)"
-        >
-        </a>
-        <diff-gutter-avatars
-          v-if="line.hasDiscussionsRight"
-          :discussions="line.right.discussions"
-          :discussions-expanded="line.right.discussionsExpanded"
-          @toggleLineDiscussions="
-            toggleLineDiscussions({
-              lineCode: line.right.line_code,
-              fileHash,
-              expanded: !line.right.discussionsExpanded,
-            })
-          "
-        />
-      </td>
-      <td
-        v-gl-tooltip.hover
-        :title="coverageState.text"
-        :class="[line.right.type, coverageState.class, { hll: isHighlighted }]"
-        class="line-coverage right-side"
-      ></td>
-      <td
-        :id="line.right.line_code"
-        :key="line.right.rich_text"
-        v-safe-html="line.right.rich_text"
-        :class="[
-          line.right.type,
-          {
-            hll: isHighlighted,
-          },
-        ]"
-        v-bind="interopRightAttributes"
-        class="line_content with-coverage parallel right-side"
-        @mousedown="handleParallelLineMouseDown"
-      ></td>
-    </template>
-    <template v-else>
-      <td class="diff-line-num old_line empty-cell"></td>
-      <td class="line-coverage right-side empty-cell"></td>
-      <td class="line_content with-coverage parallel right-side empty-cell"></td>
-    </template>
-  </tr>
-</template>

app/assets/javascripts/diffs/components/parallel_diff_view.vue

-<script>
-import { mapGetters, mapState } from 'vuex';
-import DraftNote from '~/batch_comments/components/draft_note.vue';
-import draftCommentsMixin from '~/diffs/mixins/draft_comments';
-import { getCommentedLines } from '~/notes/components/multiline_comment_utils';
-import DiffCommentCell from './diff_comment_cell.vue';
-import DiffExpansionCell from './diff_expansion_cell.vue';
-import parallelDiffTableRow from './parallel_diff_table_row.vue';
-
-export default {
-  components: {
-    DiffExpansionCell,
-    parallelDiffTableRow,
-    DiffCommentCell,
-    DraftNote,
-  },
-  mixins: [draftCommentsMixin],
-  props: {
-    diffFile: {
-      type: Object,
-      required: true,
-    },
-    diffLines: {
-      type: Array,
-      required: true,
-    },
-    helpPagePath: {
-      type: String,
-      required: false,
-      default: '',
-    },
-  },
-  computed: {
-    ...mapGetters('diffs', ['commitId']),
-    ...mapState({
-      selectedCommentPosition: ({ notes }) => notes.selectedCommentPosition,
-      selectedCommentPositionHover: ({ notes }) => notes.selectedCommentPositionHover,
-    }),
-    diffLinesLength() {
-      return this.diffLines.length;
-    },
-    commentedLines() {
-      return getCommentedLines(
-        this.selectedCommentPosition || this.selectedCommentPositionHover,
-        this.diffLines,
-      );
-    },
-  },
-  userColorScheme: window.gon.user_color_scheme,
-};
-</script>
-
-<template>
-  <table
-    :class="$options.userColorScheme"
-    :data-commit-id="commitId"
-    class="code diff-wrap-lines js-syntax-highlight text-file"
-  >
-    <colgroup>
-      <col style="width: 50px" />
-      <col style="width: 8px" />
-      <col />
-      <col style="width: 50px" />
-      <col style="width: 8px" />
-      <col />
-    </colgroup>
-    <tbody>
-      <template v-for="(line, index) in diffLines">
-        <tr
-          v-if="line.isMatchLineLeft || line.isMatchLineRight"
-          :key="`expand-${index}`"
-          class="line_expansion match"
-        >
-          <td colspan="6" class="text-center gl-font-regular">
-            <diff-expansion-cell
-              :file-hash="diffFile.file_hash"
-              :context-lines-path="diffFile.context_lines_path"
-              :line="line.left"
-              :is-top="index === 0"
-              :is-bottom="index + 1 === diffLinesLength"
-            />
-          </td>
-        </tr>
-        <parallel-diff-table-row
-          :key="line.line_code"
-          :file-hash="diffFile.file_hash"
-          :file-path="diffFile.file_path"
-          :line="line"
-          :is-bottom="index + 1 === diffLinesLength"
-          :is-commented="index >= commentedLines.startLine && index <= commentedLines.endLine"
-        />
-        <tr
-          v-if="line.renderCommentRow"
-          :key="`dcr-${line.line_code || index}`"
-          :class="line.commentRowClasses"
-          class="notes_holder"
-        >
-          <td class="notes-content parallel old" colspan="3">
-            <diff-comment-cell
-              v-if="line.left"
-              :line="line.left"
-              :diff-file-hash="diffFile.file_hash"
-              :help-page-path="helpPagePath"
-              :has-draft="line.left.hasDraft"
-              line-position="left"
-            />
-          </td>
-          <td class="notes-content parallel new" colspan="3">
-            <diff-comment-cell
-              v-if="line.right"
-              :line="line.right"
-              :diff-file-hash="diffFile.file_hash"
-              :line-index="index"
-              :help-page-path="helpPagePath"
-              :has-draft="line.right.hasDraft"
-              line-position="right"
-            />
-          </td>
-        </tr>
-        <tr
-          v-if="shouldRenderParallelDraftRow(diffFile.file_hash, line)"
-          :key="`drafts-${index}`"
-          :class="line.draftRowClasses"
-          class="notes_holder"
-        >
-          <td class="notes_line old"></td>
-          <td class="notes-content parallel old" colspan="2">
-            <div v-if="line.left && line.left.lineDraft.isDraft" class="content">
-              <draft-note :draft="line.left.lineDraft" :line="line.left" />
-            </div>
-          </td>
-          <td class="notes_line new"></td>
-          <td class="notes-content parallel new" colspan="2">
-            <div v-if="line.right && line.right.lineDraft.isDraft" class="content">
-              <draft-note :draft="line.right.lineDraft" :line="line.right" />
-            </div>
-          </td>
-        </tr>
-      </template>
-    </tbody>
-  </table>
-</template>

app/assets/javascripts/diffs/store/getters.js

@@ -151,11 +151,7 @@ export const currentDiffIndex = (state) =>
     state.diffFiles.findIndex((diff) => diff.file_hash === state.currentDiffFileId),
   );
 
-export const diffLines = (state) => (file, unifiedDiffComponents) => {
-  if (!unifiedDiffComponents && state.diffViewType === INLINE_DIFF_VIEW_TYPE) {
-    return null;
-  }
-
+export const diffLines = (state) => (file) => {
   return parallelizeDiffLines(
     file.highlighted_diff_lines || [],
     state.diffViewType === INLINE_DIFF_VIEW_TYPE,

app/controllers/projects/merge_requests_controller.rb

@@ -33,7 +33,6 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
     push_frontend_feature_flag(:approvals_commented_by, @project, default_enabled: true)
     push_frontend_feature_flag(:merge_request_widget_graphql, @project, default_enabled: :yaml)
     push_frontend_feature_flag(:drag_comment_selection, @project, default_enabled: true)
-    push_frontend_feature_flag(:unified_diff_components, @project, default_enabled: true)
     push_frontend_feature_flag(:default_merge_ref_for_diffs, @project, default_enabled: :yaml)
     push_frontend_feature_flag(:core_security_mr_widget_counts, @project)
     push_frontend_feature_flag(:diffs_gradual_load, @project, default_enabled: true)

config/feature_flags/development/unified_diff_components.yml

----
-name: unified_diff_components
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/44974
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/268039
-type: development
-group: group::code review
-default_enabled: true
-milestone: '13.6'

ee/app/assets/javascripts/diffs/components/diff_row_utils.js

-import {
-  mapParallel as CEMapParallel,
-  mapInline as CEMapInline,
-} from '~/diffs/components/diff_row_utils';
+import { mapParallel as CEMapParallel } from '~/diffs/components/diff_row_utils';
 
 export const mapParallel = (content) => (line) => {
   let { left, right } = line;
@@ -27,5 +24,3 @@ export const mapParallel = (content) => (line) => {
     }),
   };
 };
-
-export const mapInline = CEMapInline;

spec/features/merge_request/batch_comments_spec.rb

@@ -259,8 +259,8 @@ RSpec.describe 'Merge request > Batch comments', :js do
   end
 
   def write_parallel_comment(line, **params)
-    find("td[id='#{line}']").hover
-    find(".is-over button").click
+    find("div[id='#{line}']").hover
+    find(".js-add-diff-note-button").click
 
     write_comment(selector: "form[data-line-code='#{line}']", **params)
   end

spec/features/merge_request/user_comments_on_diff_spec.rb

@@ -132,7 +132,7 @@ RSpec.describe 'User comments on a diff', :js do
       # In `files/ruby/popen.rb`
       it 'allows comments for changes involving both sides' do
         # click +15, select -13 add and verify comment
-        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .new_line a[data-linenumber="15"]').find(:xpath, '../..'), 'right')
+        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .right-side a[data-linenumber="15"]').find(:xpath, '../../..'), 'right')
         add_comment('-13', '+15')
       end
 
@@ -141,7 +141,7 @@ RSpec.describe 'User comments on a diff', :js do
         page.within('[data-path="files/ruby/popen.rb"]') do
           all('.js-unfold-all')[0].click
         end
-        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .old_line a[data-linenumber="9"]').find(:xpath, '../..'), 'left')
+        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .left-side a[data-linenumber="9"]').find(:xpath, '../..'), 'left')
         add_comment('1', '-9')
       end
 
@@ -150,7 +150,7 @@ RSpec.describe 'User comments on a diff', :js do
         page.within('[data-path="files/ruby/popen.rb"]') do
           all('.js-unfold-all')[1].click
         end
-        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .old_line a[data-linenumber="21"]').find(:xpath, '../..'), 'left')
+        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .left-side a[data-linenumber="21"]').find(:xpath, '../..'), 'left')
         add_comment('18', '21')
       end
 
@@ -159,7 +159,7 @@ RSpec.describe 'User comments on a diff', :js do
         page.within('[data-path="files/ruby/popen.rb"]') do
           all('.js-unfold-down')[1].click
         end
-        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .old_line a[data-linenumber="30"]').find(:xpath, '../..'), 'left')
+        click_diff_line(find('div[data-path="files/ruby/popen.rb"] .left-side a[data-linenumber="30"]').find(:xpath, '../..'), 'left')
         add_comment('+28', '37')
       end
     end

spec/features/merge_request/user_interacts_with_batched_mr_diffs_spec.rb

@@ -16,14 +16,14 @@ RSpec.describe 'Batch diffs', :js do
     wait_for_requests
 
     # Add discussion to first line of first file
-    click_diff_line(find('.diff-file.file-holder:first-of-type tr.line_holder.new:first-of-type'))
+    click_diff_line(find('.diff-file.file-holder:first-of-type .line_holder .left-side:first-of-type'))
     page.within('.js-discussion-note-form') do
       fill_in('note_note', with: 'First Line Comment')
       click_button('Add comment now')
     end
 
     # Add discussion to first line of last file
-    click_diff_line(find('.diff-file.file-holder:last-of-type tr.line_holder.new:first-of-type'))
+    click_diff_line(find('.diff-file.file-holder:last-of-type .line_holder .left-side:first-of-type'))
     page.within('.js-discussion-note-form') do
       fill_in('note_note', with: 'Last Line Comment')
       click_button('Add comment now')

spec/features/merge_request/user_posts_diff_notes_spec.rb

@@ -10,7 +10,7 @@ RSpec.describe 'Merge request > User posts diff notes', :js do
   let(:user) { project.creator }
   let(:comment_button_class) { '.add-diff-note' }
   let(:notes_holder_input_class) { 'js-temp-notes-holder' }
-  let(:notes_holder_input_xpath) { './following-sibling::*[contains(concat(" ", @class, " "), " notes_holder ")]' }
+  let(:notes_holder_input_xpath) { '..//following-sibling::*[contains(concat(" ", @class, " "), " notes_holder ")]' }
   let(:test_note_comment) { 'this is a test note!' }
 
   before do
@@ -27,7 +27,7 @@ RSpec.describe 'Merge request > User posts diff notes', :js do
 
     context 'with an old line on the left and no line on the right' do
       it 'allows commenting on the left side' do
-        should_allow_commenting(find('[id="6eb14e00385d2fb284765eb1cd8d420d33d63fc9_23_22"]').find(:xpath, '..'), 'left')
+        should_allow_commenting(find('[id="6eb14e00385d2fb284765eb1cd8d420d33d63fc9_23_22"]'), 'left')
       end
 
       it 'does not allow commenting on the right side' do
@@ -67,7 +67,7 @@ RSpec.describe 'Merge request > User posts diff notes', :js do
 
     context 'with a match line' do
       it 'does not allow commenting' do
-        line_holder = find('.match', match: :first).find(:xpath, '..')
+        line_holder = find('.match', match: :first)
         match_should_not_allow_commenting(line_holder)
       end
     end
@@ -81,17 +81,13 @@ RSpec.describe 'Merge request > User posts diff notes', :js do
         wait_for_requests
       end
 
-      # The first `.js-unfold` unfolds upwards, therefore the first
-      # `.line_holder` will be an unfolded line.
-      let(:line_holder) { first('#a5cc2925ca8258af241be7e5b0381edf30266302 .line_holder') }
-
       it 'allows commenting on the left side' do
-        should_allow_commenting(line_holder, 'left')
+        should_allow_commenting(first('#a5cc2925ca8258af241be7e5b0381edf30266302 .line_holder [data-testid="left-side"]'))
       end
 
       it 'allows commenting on the right side' do
         # Automatically shifts comment box to left side.
-        should_allow_commenting(line_holder, 'right')
+        should_allow_commenting(first('#a5cc2925ca8258af241be7e5b0381edf30266302 .line_holder [data-testid="right-side"]'))
       end
     end
   end
@@ -149,7 +145,7 @@ RSpec.describe 'Merge request > User posts diff notes', :js do
 
       # The first `.js-unfold` unfolds upwards, therefore the first
       # `.line_holder` will be an unfolded line.
-      let(:line_holder) { first('.line_holder[id="a5cc2925ca8258af241be7e5b0381edf30266302_1_1"]') }
+      let(:line_holder) { first('[id="a5cc2925ca8258af241be7e5b0381edf30266302_1_1"]') }
 
       it 'allows commenting' do
         should_allow_commenting line_holder

spec/features/merge_request/user_sees_versions_spec.rb

@@ -30,8 +30,8 @@ RSpec.describe 'Merge request > User sees versions', :js do
       line_code = "#{file_id}_#{line_code}"
 
       page.within(diff_file_selector) do
-        find(".line_holder[id='#{line_code}'] td:nth-of-type(1)").hover
-        find(".line_holder[id='#{line_code}'] button").click
+        first("[id='#{line_code}']").hover
+        first("[id='#{line_code}'] [role='button']").click
 
         page.within("form[data-line-code='#{line_code}']") do
           fill_in "note[note]", with: comment

spec/features/merge_request/user_views_diffs_spec.rb

@@ -24,7 +24,7 @@ RSpec.describe 'User views diffs', :js do
 
       page.within('.file-holder[id="2f6fcd96b88b36ce98c38da085c795a27d92a3dd"]') do
         expect(find('.text-file')).to have_content('fileutils')
-        expect(page).to have_selector('.new_line [data-linenumber="1"]', count: 1)
+        expect(page).to have_selector('[data-interop-type="new"] [data-linenumber="1"]')
       end
     end
 
@@ -32,8 +32,8 @@ RSpec.describe 'User views diffs', :js do
       page.within('.file-holder[id="2f6fcd96b88b36ce98c38da085c795a27d92a3dd"]') do
         all('.js-unfold-all')[1].click
 
-        expect(page).to have_selector('.new_line [data-linenumber="24"]', count: 1)
-        expect(page).not_to have_selector('.new_line [data-linenumber="1"]')
+        expect(page).to have_selector('[data-interop-type="new"] [data-linenumber="24"]', count: 1)
+        expect(page).not_to have_selector('[data-interop-type="new"] [data-linenumber="1"]')
       end
     end
 

spec/frontend/diffs/components/diff_content_spec.js

@@ -4,8 +4,6 @@ import Vuex from 'vuex';
 import DiffContentComponent from '~/diffs/components/diff_content.vue';
 import DiffDiscussions from '~/diffs/components/diff_discussions.vue';
 import DiffView from '~/diffs/components/diff_view.vue';
-import InlineDiffView from '~/diffs/components/inline_diff_view.vue';
-import ParallelDiffView from '~/diffs/components/parallel_diff_view.vue';
 import { IMAGE_DIFF_POSITION_TYPE } from '~/diffs/constants';
 import { diffViewerModes } from '~/ide/constants';
 import NoteForm from '~/notes/components/note_form.vue';
@@ -107,25 +105,10 @@ describe('DiffContent', () => {
     });
 
     const textDiffFile = { ...defaultProps.diffFile, viewer: { name: diffViewerModes.text } };
-    it('should render diff inline view if `isInlineView` is true', () => {
-      isInlineViewGetterMock.mockReturnValue(true);
-      createComponent({ props: { diffFile: textDiffFile } });
-
-      expect(wrapper.find(InlineDiffView).exists()).toBe(true);
-    });
-
-    it('should render parallel view if `isParallelView` getter is true', () => {
-      isParallelViewGetterMock.mockReturnValue(true);
-      createComponent({ props: { diffFile: textDiffFile } });
-
-      expect(wrapper.find(ParallelDiffView).exists()).toBe(true);
-    });
 
     it('should render diff view if `unifiedDiffComponents` are true', () => {
-      isParallelViewGetterMock.mockReturnValue(true);
       createComponent({
         props: { diffFile: textDiffFile },
-        provide: { glFeatures: { unifiedDiffComponents: true } },
       });
 
       expect(wrapper.find(DiffView).exists()).toBe(true);

spec/frontend/diffs/components/diff_row_utils_spec.js

@@ -258,30 +258,3 @@ describe('mapParallel', () => {
     expect(mapped.right).toMatchObject(rightExpectation);
   });
 });
-
-describe('mapInline', () => {
-  it('should assign computed properties to the line object', () => {
-    const content = {
-      diffFile: {},
-      shouldRenderDraftRow: () => false,
-    };
-    const line = {
-      discussions: [{}],
-      discussionsExpanded: true,
-      hasForm: true,
-    };
-    const expectation = {
-      commentRowClasses: '',
-      hasDiscussions: true,
-      isContextLine: false,
-      isMatchLine: false,
-      isMetaLine: false,
-      renderDiscussion: true,
-      hasDraft: false,
-      hasCommentForm: true,
-    };
-    const mapped = utils.mapInline(content)(line);
-
-    expect(mapped).toMatchObject(expectation);
-  });
-});

spec/frontend/diffs/components/inline_diff_view_spec.js

-import '~/behaviors/markdown/render_gfm';
-import { getByText } from '@testing-library/dom';
-import { mount } from '@vue/test-utils';
-import { mapInline } from '~/diffs/components/diff_row_utils';
-import InlineDiffView from '~/diffs/components/inline_diff_view.vue';
-import { createStore } from '~/mr_notes/stores';
-import discussionsMockData from '../mock_data/diff_discussions';
-import diffFileMockData from '../mock_data/diff_file';
-
-describe('InlineDiffView', () => {
-  let wrapper;
-  const getDiffFileMock = () => ({ ...diffFileMockData });
-  const getDiscussionsMockData = () => [{ ...discussionsMockData }];
-  const notesLength = getDiscussionsMockData()[0].notes.length;
-
-  const setup = (diffFile, diffLines) => {
-    const mockDiffContent = {
-      diffFile,
-      shouldRenderDraftRow: jest.fn(),
-    };
-
-    const store = createStore();
-
-    store.dispatch('diffs/setInlineDiffViewType');
-    wrapper = mount(InlineDiffView, {
-      store,
-      propsData: {
-        diffFile,
-        diffLines: diffLines.map(mapInline(mockDiffContent)),
-      },
-    });
-  };
-
-  describe('template', () => {
-    it('should have rendered diff lines', () => {
-      const diffFile = getDiffFileMock();
-      setup(diffFile, diffFile.highlighted_diff_lines);
-
-      expect(wrapper.findAll('tr.line_holder').length).toEqual(8);
-      expect(wrapper.findAll('tr.line_holder.new').length).toEqual(4);
-      expect(wrapper.findAll('tr.line_expansion.match').length).toEqual(1);
-      getByText(wrapper.element, /Bad dates/i);
-    });
-
-    it('should render discussions', () => {
-      const diffFile = getDiffFileMock();
-      diffFile.highlighted_diff_lines[1].discussions = getDiscussionsMockData();
-      diffFile.highlighted_diff_lines[1].discussionsExpanded = true;
-      setup(diffFile, diffFile.highlighted_diff_lines);
-
-      expect(wrapper.findAll('.notes_holder').length).toEqual(1);
-      expect(wrapper.findAll('.notes_holder .note').length).toEqual(notesLength + 1);
-      getByText(wrapper.element, 'comment 5');
-      wrapper.vm.$store.dispatch('setInitialNotes', []);
-    });
-  });
-});

spec/frontend/diffs/components/parallel_diff_view_spec.js

-import { shallowMount, createLocalVue } from '@vue/test-utils';
-import Vuex from 'vuex';
-import parallelDiffTableRow from '~/diffs/components/parallel_diff_table_row.vue';
-import ParallelDiffView from '~/diffs/components/parallel_diff_view.vue';
-import { createStore } from '~/mr_notes/stores';
-import diffFileMockData from '../mock_data/diff_file';
-
-let wrapper;
-const localVue = createLocalVue();
-
-localVue.use(Vuex);
-
-function factory() {
-  const diffFile = { ...diffFileMockData };
-  const store = createStore();
-
-  wrapper = shallowMount(ParallelDiffView, {
-    localVue,
-    store,
-    propsData: {
-      diffFile,
-      diffLines: diffFile.parallel_diff_lines,
-    },
-  });
-}
-
-describe('ParallelDiffView', () => {
-  afterEach(() => {
-    wrapper.destroy();
-  });
-
-  it('renders diff lines', () => {
-    factory();
-
-    expect(wrapper.findAll(parallelDiffTableRow).length).toBe(8);
-  });
-});

spec/frontend_integration/diffs/diffs_interopability_spec.js

@@ -8,15 +8,6 @@ import {
   getCodeElementFromLineNumber,
 } from './diffs_interopability_api';
 
-jest.mock('~/vue_shared/mixins/gl_feature_flags_mixin', () => () => ({
-  inject: {
-    glFeatures: {
-      from: 'window.gon.features',
-      default: () => global.window.gon?.features,
-    },
-  },
-}));
-
 const TEST_PROJECT_PATH = 'gitlab-org/gitlab-test';
 const TEST_BASE_URL = `/${TEST_PROJECT_PATH}/-/merge_requests/1/`;
 const TEST_DIFF_FILE = 'files/js/commit.coffee';
@@ -114,48 +105,41 @@ describe('diffs third party interoperability', () => {
     );
 
   describe.each`
-    desc                          | unifiedDiffComponents | view          | rowSelector               | codeSelector                          | expectation
-    ${'inline view'}              | ${false}              | ${'inline'}   | ${'tr.line_holder'}       | ${'td.line_content'}                  | ${EXPECT_INLINE}
-    ${'parallel view left side'}  | ${false}              | ${'parallel'} | ${'tr.line_holder'}       | ${'td.line_content.left-side'}        | ${EXPECT_PARALLEL_LEFT_SIDE}
-    ${'parallel view right side'} | ${false}              | ${'parallel'} | ${'tr.line_holder'}       | ${'td.line_content.right-side'}       | ${EXPECT_PARALLEL_RIGHT_SIDE}
-    ${'inline view'}              | ${true}               | ${'inline'}   | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content'}            | ${EXPECT_INLINE}
-    ${'parallel view left side'}  | ${true}               | ${'parallel'} | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content.left-side'}  | ${EXPECT_PARALLEL_LEFT_SIDE}
-    ${'parallel view right side'} | ${true}               | ${'parallel'} | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content.right-side'} | ${EXPECT_PARALLEL_RIGHT_SIDE}
-  `(
-    '$desc (unifiedDiffComponents=$unifiedDiffComponents)',
-    ({ unifiedDiffComponents, view, rowSelector, codeSelector, expectation }) => {
-      beforeEach(async () => {
-        global.jsdom.reconfigure({
-          url: `${TEST_HOST}/${TEST_BASE_URL}/diffs?view=${view}`,
-        });
-        window.gon.features = { unifiedDiffComponents };
-
-        vm = startDiffsApp();
-
-        await waitFor(() => expect(hasLines(rowSelector)).toBe(true));
+    desc                          | view          | rowSelector               | codeSelector                          | expectation
+    ${'inline view'}              | ${'inline'}   | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content'}            | ${EXPECT_INLINE}
+    ${'parallel view left side'}  | ${'parallel'} | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content.left-side'}  | ${EXPECT_PARALLEL_LEFT_SIDE}
+    ${'parallel view right side'} | ${'parallel'} | ${'.diff-tr.line_holder'} | ${'.diff-td.line_content.right-side'} | ${EXPECT_PARALLEL_RIGHT_SIDE}
+  `('$desc', ({ view, rowSelector, codeSelector, expectation }) => {
+    beforeEach(async () => {
+      global.jsdom.reconfigure({
+        url: `${TEST_HOST}/${TEST_BASE_URL}/diffs?view=${view}`,
       });
 
-      it('should match diff model', () => {
-        const lines = findLineElements(rowSelector);
-        const codes = findCodeElements(lines, codeSelector);
+      vm = startDiffsApp();
 
-        expect(getCodeElementsInteropModel(codes)).toEqual(expectation);
-      });
+      await waitFor(() => expect(hasLines(rowSelector)).toBe(true));
+    });
+
+    it('should match diff model', () => {
+      const lines = findLineElements(rowSelector);
+      const codes = findCodeElements(lines, codeSelector);
+
+      expect(getCodeElementsInteropModel(codes)).toEqual(expectation);
+    });
 
-      it.each`
-        lineNumber | part      | expectedText
-        ${4}       | ${'base'} | ${'new CommitFile(this)'}
-        ${4}       | ${'head'} | ${'new CommitFile(@)'}
-        ${2}       | ${'base'} | ${'constructor: ->'}
-        ${2}       | ${'head'} | ${'constructor: ->'}
-      `(
-        'should find code element lineNumber=$lineNumber part=$part',
-        ({ lineNumber, part, expectedText }) => {
-          const codeElement = getCodeElementFromLineNumber(findDiffFile(), lineNumber, part);
-
-          expect(codeElement.textContent.trim()).toBe(expectedText);
-        },
-      );
-    },
-  );
+    it.each`
+      lineNumber | part      | expectedText
+      ${4}       | ${'base'} | ${'new CommitFile(this)'}
+      ${4}       | ${'head'} | ${'new CommitFile(@)'}
+      ${2}       | ${'base'} | ${'constructor: ->'}
+      ${2}       | ${'head'} | ${'constructor: ->'}
+    `(
+      'should find code element lineNumber=$lineNumber part=$part',
+      ({ lineNumber, part, expectedText }) => {
+        const codeElement = getCodeElementFromLineNumber(findDiffFile(), lineNumber, part);
+
+        expect(codeElement.textContent.trim()).toBe(expectedText);
+      },
+    );
+  });
 });

spec/spec_helper.rb

@@ -267,7 +267,6 @@ RSpec.configure do |config|
       # See https://gitlab.com/gitlab-org/gitlab/-/issues/33867
       stub_feature_flags(file_identifier_hash: false)
 
-      stub_feature_flags(unified_diff_components: false)
       stub_feature_flags(diffs_virtual_scrolling: false)
 
       # The following `vue_issues_list`/`vue_issuables_list` stubs can be removed

spec/support/helpers/merge_request_diff_helpers.rb

@@ -3,8 +3,8 @@
 module MergeRequestDiffHelpers
   def click_diff_line(line_holder, diff_side = nil)
     line = get_line_components(line_holder, diff_side)
-    line[:content].hover
-    line[:num].find('.js-add-diff-note-button', visible: false).send_keys(:return)
+    line_holder.hover
+    line[:num].find('.js-add-diff-note-button').click
   end
 
   def get_line_components(line_holder, diff_side = nil)