Merge "Change diff-new to diff-old forking"
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.ts b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.ts
index 24f5932..abb637c 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.ts
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.ts
@@ -46,8 +46,8 @@
 import {DiffPreferencesInfo} from '../../../types/diff';
 import {GrDiffHost} from '../../diff/gr-diff-host/gr-diff-host';
 import {GrDiffPreferencesDialog} from '../../diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog';
-import {GrDiffCursor} from '../../../embed/diff/gr-diff-cursor/gr-diff-cursor';
-import {GrDiffCursor as GrDiffCursorNew} from '../../../embed/diff-new/gr-diff-cursor/gr-diff-cursor';
+import {GrDiffCursor as GrDiffCursorNew} from '../../../embed/diff/gr-diff-cursor/gr-diff-cursor';
+import {GrDiffCursor} from '../../../embed/diff-old/gr-diff-cursor/gr-diff-cursor';
 import {GrCursorManager} from '../../shared/gr-cursor-manager/gr-cursor-manager';
 import {ChangeComments} from '../../diff/gr-comment-api/gr-comment-api';
 import {ParsedChangeInfo, PatchSetFile} from '../../../types/types';
diff --git a/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts b/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
index 8e30143..7723c66 100644
--- a/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
+++ b/polygerrit-ui/app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog.ts
@@ -7,7 +7,7 @@
 import '../../shared/gr-dialog/gr-dialog';
 import '../../shared/gr-icon/gr-icon';
 import '../../../embed/diff/gr-diff/gr-diff';
-import '../../../embed/diff-new/gr-diff/gr-diff';
+import '../../../embed/diff-old/gr-diff/gr-diff';
 import {navigationToken} from '../../core/gr-navigation/gr-navigation';
 import {
   NumericChangeId,
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
index 2aae2ea..33c8c22 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.ts
@@ -6,7 +6,7 @@
 import '../../shared/gr-comment-thread/gr-comment-thread';
 import '../../checks/gr-diff-check-result';
 import '../../../embed/diff/gr-diff/gr-diff';
-import '../../../embed/diff-new/gr-diff/gr-diff';
+import '../../../embed/diff-old/gr-diff/gr-diff';
 import {
   anyLineTooLong,
   getDiffLength,
@@ -46,8 +46,8 @@
   IgnoreWhitespaceType,
   WebLinkInfo,
 } from '../../../types/diff';
-import {GrDiff} from '../../../embed/diff/gr-diff/gr-diff';
-import {GrDiff as GrDiffNew} from '../../../embed/diff-new/gr-diff/gr-diff';
+import {GrDiff as GrDiffNew} from '../../../embed/diff/gr-diff/gr-diff';
+import {GrDiff} from '../../../embed/diff-old/gr-diff/gr-diff';
 import {DiffViewMode, Side, CommentSide} from '../../../constants/constants';
 import {FilesWebLinks} from '../gr-patch-range-select/gr-patch-range-select';
 import {GrCommentThread} from '../../shared/gr-comment-thread/gr-comment-thread';
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
index 7ab8c2c..0b14f4f 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.ts
@@ -53,8 +53,8 @@
   FilesWebLinks,
   PatchRangeChangeEvent,
 } from '../gr-patch-range-select/gr-patch-range-select';
-import {GrDiffCursor} from '../../../embed/diff/gr-diff-cursor/gr-diff-cursor';
-import {GrDiffCursor as GrDiffCursorNew} from '../../../embed/diff-new/gr-diff-cursor/gr-diff-cursor';
+import {GrDiffCursor as GrDiffCursorNew} from '../../../embed/diff/gr-diff-cursor/gr-diff-cursor';
+import {GrDiffCursor} from '../../../embed/diff-old/gr-diff-cursor/gr-diff-cursor';
 import {CommentSide, DiffViewMode, Side} from '../../../constants/constants';
 import {GrApplyFixDialog} from '../gr-apply-fix-dialog/gr-apply-fix-dialog';
 import {OpenFixPreviewEvent, ValueChangedEvent} from '../../../types/events';
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.ts b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.ts
index d43dadc..348ea3b 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.ts
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.ts
@@ -8,7 +8,7 @@
 import '../gr-comment/gr-comment';
 import '../gr-icon/gr-icon';
 import '../../../embed/diff/gr-diff/gr-diff';
-import '../../../embed/diff-new/gr-diff/gr-diff';
+import '../../../embed/diff-old/gr-diff/gr-diff';
 import '../gr-copy-clipboard/gr-copy-clipboard';
 import {css, html, nothing, LitElement, PropertyValues} from 'lit';
 import {
diff --git a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section.ts b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section.ts
similarity index 96%
rename from polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section.ts
rename to polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section.ts
index 81fba83..e558295 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section.ts
@@ -124,8 +124,7 @@
   }
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define(
     'gr-context-controls-section',
     GrContextControlsSection
@@ -134,7 +133,6 @@
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-context-controls-section': LitElement;
   }
 }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section_test.ts b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section_test.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section_test.ts
index 5ac57e7..6a557fc 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls-section_test.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls-section_test.ts
@@ -4,7 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 import '../../../test/common-test-setup';
-
 import './gr-context-controls-section';
 import {GrContextControlsSection} from './gr-context-controls-section';
 import {fixture, html, assert} from '@open-wc/testing';
diff --git a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls.ts b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls.ts
similarity index 98%
rename from polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls.ts
rename to polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls.ts
index 0ea6490..5695f4d 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls.ts
@@ -369,7 +369,7 @@
           buttonType: type,
           expandedLines: linesToExpand,
         });
-        fire(this, 'diff-context-expanded-internal-new', {
+        fire(this, 'diff-context-expanded-internal', {
           contextGroup: this.group,
           groups,
           numLines: this.numLines(),
@@ -515,15 +515,12 @@
     `;
   }
 }
-
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-context-controls', GrContextControls);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-context-controls': LitElement;
   }
 }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls_test.ts b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls_test.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls_test.ts
index 7f5827c..196afe5 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-context-controls/gr-context-controls_test.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-context-controls/gr-context-controls_test.ts
@@ -23,7 +23,6 @@
   let element: GrContextControls;
 
   setup(async () => {
-    // TODO(newdiff-cleanup): Remove cast when newdiff migration is complete.
     element = document.createElement(
       'gr-context-controls'
     ) as GrContextControls;
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-binary.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-binary.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-binary.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-binary.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-element.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-element.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-element.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-element.ts
index 009cbf9..e6de72d 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-element.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-element.ts
@@ -350,7 +350,7 @@
   init() {
     this.cleanup();
     this.diffElement?.addEventListener(
-      'diff-context-expanded-internal-new',
+      'diff-context-expanded-internal',
       this.onDiffContextExpanded
     );
     this.builder?.init();
@@ -367,7 +367,7 @@
     this.processor?.cancel();
     this.builder?.cleanup();
     this.diffElement?.removeEventListener(
-      'diff-context-expanded-internal-new',
+      'diff-context-expanded-internal',
       this.onDiffContextExpanded
     );
   }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-element_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-element_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-element_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-element_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-image.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-image.ts
similarity index 95%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-image.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-image.ts
index 869d600..d71d52a 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder-image.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder-image.ts
@@ -10,8 +10,8 @@
 import {html, LitElement, nothing} from 'lit';
 import {property, query, state} from 'lit/decorators.js';
 import {GrDiffBuilder} from './gr-diff-builder';
+import {createElementDiff, isNewDiff} from '../../diff/gr-diff/gr-diff-utils';
 import {GrDiffGroup} from '../gr-diff/gr-diff-group';
-import {isNewDiff, createElementDiff} from '../../diff/gr-diff/gr-diff-utils';
 
 // MIME types for images we allow showing. Do not include SVG, it can contain
 // arbitrary JavaScript.
@@ -45,7 +45,6 @@
   }
 
   private createImageDiffNew() {
-    // TODO(newdiff-cleanup): Remove cast when newdiff migration is complete.
     const imageDiff = document.createElement(
       'gr-diff-image-new'
     ) as GrDiffImageNew;
@@ -56,7 +55,6 @@
   }
 
   private createImageDiffOld() {
-    // TODO(newdiff-cleanup): Remove cast when newdiff migration is complete.
     const imageDiff = document.createElement(
       'gr-diff-image-old'
     ) as GrDiffImageOld;
@@ -268,15 +266,13 @@
     : '';
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-diff-image-new', GrDiffImageNew);
   customElements.define('gr-diff-image-old', GrDiffImageOld);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-diff-image-new': LitElement;
     'gr-diff-image-old': LitElement;
   }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder.ts
similarity index 98%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder.ts
index 43c7775..951466f 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-builder.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-builder.ts
@@ -34,7 +34,7 @@
 
 declare global {
   interface HTMLElementEventMap {
-    'diff-context-expanded-internal-new': CustomEvent<DiffContextExpandedEventDetail>;
+    'diff-context-expanded-internal': CustomEvent<DiffContextExpandedEventDetail>;
     'diff-context-expanded': CustomEvent<DiffContextExpandedExternalDetail>;
     'content-load-needed': CustomEvent<ContentLoadNeededEventDetail>;
   }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-row.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-row.ts
similarity index 98%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-row.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-row.ts
index 785f5a6..f2742c7 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-row.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-row.ts
@@ -443,7 +443,7 @@
   private renderText(side: Side) {
     const line = this.line(side);
     const lineNumber = this.lineNumber(side);
-    if (lineNumber === FILE || lineNumber === LOST) return;
+    if (typeof lineNumber !== 'number') return;
 
     // Note that `this.layersApplied` will wipe away the <gr-diff-text>, and
     // another rendering cycle will be initiated in `updated()`.
@@ -473,14 +473,12 @@
   }
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-diff-row', GrDiffRow);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-diff-row': LitElement;
   }
 }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-row_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-row_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-row_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-row_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-section.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-section.ts
similarity index 97%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-section.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-section.ts
index d80abd8..28919e8 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-section.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-section.ts
@@ -16,9 +16,9 @@
 } from '../../../api/diff';
 import {GrDiffGroup, GrDiffGroupType} from '../gr-diff/gr-diff-group';
 import {
-  isNewDiff,
   diffClasses,
   getResponsiveMode,
+  isNewDiff,
 } from '../../diff/gr-diff/gr-diff-utils';
 import {GrDiffRow} from './gr-diff-row';
 import '../gr-context-controls/gr-context-controls-section';
@@ -243,14 +243,12 @@
   }
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-diff-section', GrDiffSection);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-diff-section': LitElement;
   }
 }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-section_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-section_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-section_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-section_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text.ts
similarity index 95%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text.ts
index c447ee4..3878402 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text.ts
@@ -6,7 +6,7 @@
 import {LitElement, html, TemplateResult} from 'lit';
 import {property} from 'lit/decorators.js';
 import {styleMap} from 'lit/directives/style-map.js';
-import {isNewDiff, diffClasses} from '../../diff/gr-diff/gr-diff-utils';
+import {diffClasses, isNewDiff} from '../../diff/gr-diff/gr-diff-utils';
 
 const SURROGATE_PAIR = /[\uD800-\uDBFF][\uDC00-\uDFFF]/;
 
@@ -144,14 +144,12 @@
   }
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-diff-text', GrDiffText);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-diff-text': LitElement;
   }
 }
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text_test.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text_test.ts
index 344240b..3858bed 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-builder/gr-diff-text_test.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-builder/gr-diff-text_test.ts
@@ -4,7 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 import '../../../test/common-test-setup';
-
 import './gr-diff-text';
 import {GrDiffText} from './gr-diff-text';
 import {fixture, html, assert} from '@open-wc/testing';
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-cursor/gr-diff-cursor.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-cursor/gr-diff-cursor.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-cursor/gr-diff-cursor.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-cursor/gr-diff-cursor.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-cursor/gr-diff-cursor_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-cursor/gr-diff-cursor_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-cursor/gr-diff-cursor_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-cursor/gr-diff-cursor_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-annotation.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-annotation.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-annotation.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-annotation.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-annotation_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-annotation_test.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-annotation_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-annotation_test.ts
index 3e1ce66..f319a3c 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-annotation_test.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-annotation_test.ts
@@ -3,6 +3,7 @@
  * Copyright 2016 Google LLC
  * SPDX-License-Identifier: Apache-2.0
  */
+
 import '../../../test/common-test-setup';
 import {GrAnnotation} from './gr-annotation';
 import {
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-diff-highlight.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-diff-highlight.ts
similarity index 98%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-diff-highlight.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-diff-highlight.ts
index dad8df6..2c0663d 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-diff-highlight.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-diff-highlight.ts
@@ -18,13 +18,8 @@
   GrDiffThreadElement,
 } from '../../diff/gr-diff/gr-diff-utils';
 import {debounce, DelayedTask} from '../../../utils/async-util';
-import {
-  assert,
-  assertIsDefined,
-  queryAndAssert,
-} from '../../../utils/common-util';
+import {assertIsDefined, queryAndAssert} from '../../../utils/common-util';
 import {fire} from '../../../utils/event-util';
-import {FILE, LOST} from '../../../api/diff';
 
 interface SidedRange {
   side: Side;
@@ -312,8 +307,7 @@
     const side = getSideByLineEl(lineEl);
     if (!side) return null;
     const line = getLineNumberByChild(lineEl);
-    if (!line || line === FILE || line === LOST) return null;
-    assert(typeof line === 'number', 'line must be a number');
+    if (typeof line !== 'number') return null;
     const contentTd = this.diffBuilder.getContentTdByLineEl(lineEl);
     if (!contentTd) return null;
     const contentText = contentTd.querySelector('.contentText');
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-diff-highlight_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-diff-highlight_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-diff-highlight_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-diff-highlight_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-range-normalizer.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-range-normalizer.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-highlight/gr-range-normalizer.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-highlight/gr-range-normalizer.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-model/gr-diff-model.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-model/gr-diff-model.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-model/gr-diff-model.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-model/gr-diff-model.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-processor/gr-diff-processor.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-processor/gr-diff-processor.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-processor/gr-diff-processor.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-processor/gr-diff-processor.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-processor/gr-diff-processor_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-processor/gr-diff-processor_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-processor/gr-diff-processor_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-processor/gr-diff-processor_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-selection/gr-diff-selection.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-selection/gr-diff-selection.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-selection/gr-diff-selection.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-selection/gr-diff-selection.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff-selection/gr-diff-selection_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff-selection/gr-diff-selection_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff-selection/gr-diff-selection_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff-selection/gr-diff-selection_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-group.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-group.ts
similarity index 98%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-group.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-group.ts
index c11cfb6..771e298 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-group.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-group.ts
@@ -4,14 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 import {BLANK_LINE, GrDiffLine} from './gr-diff-line';
-import {
-  FILE,
-  GrDiffLineType,
-  LOST,
-  LineNumber,
-  LineRange,
-  Side,
-} from '../../../api/diff';
+import {GrDiffLineType, LineNumber, LineRange, Side} from '../../../api/diff';
 import {assertIsDefined, assert} from '../../../utils/common-util';
 import {untilRendered} from '../../../utils/dom-util';
 import {isDefined} from '../../../types/types';
@@ -503,8 +496,7 @@
     // untilRendered() promise.
     if (
       this.skip !== undefined ||
-      lineNumber === LOST ||
-      lineNumber === FILE ||
+      typeof lineNumber !== 'number' ||
       this.type === GrDiffGroupType.CONTEXT_CONTROL
     ) {
       return Promise.resolve();
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-group_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-group_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-group_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-group_test.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-line.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-line.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-line.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-line.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-styles.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-styles.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff-styles.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff-styles.ts
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff.ts
similarity index 99%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff.ts
index 1beaf6e..2aa8096 100644
--- a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff.ts
+++ b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff.ts
@@ -1109,14 +1109,12 @@
   return mutations.flatMap(mutation => [...mutation.removedNodes]);
 }
 
-// TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (isNewDiff()) {
+if (!isNewDiff()) {
   customElements.define('gr-diff', GrDiff);
 }
 
 declare global {
   interface HTMLElementTagNameMap {
-    // TODO(newdiff-cleanup): Replace once newdiff migration is completed.
     'gr-diff': LitElement;
   }
   interface HTMLElementEventMap {
diff --git a/polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff_test.ts b/polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff_test.ts
similarity index 100%
rename from polygerrit-ui/app/embed/diff-new/gr-diff/gr-diff_test.ts
rename to polygerrit-ui/app/embed/diff-old/gr-diff/gr-diff_test.ts
diff --git a/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls-section.ts b/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls-section.ts
index 132751f..36e1f1a 100644
--- a/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls-section.ts
+++ b/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls-section.ts
@@ -125,7 +125,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define(
     'gr-context-controls-section',
     GrContextControlsSection
diff --git a/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls.ts b/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls.ts
index 2639a3d..43c8113 100644
--- a/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls.ts
+++ b/polygerrit-ui/app/embed/diff/gr-context-controls/gr-context-controls.ts
@@ -369,7 +369,7 @@
           buttonType: type,
           expandedLines: linesToExpand,
         });
-        fire(this, 'diff-context-expanded-internal', {
+        fire(this, 'diff-context-expanded-internal-new', {
           contextGroup: this.group,
           groups,
           numLines: this.numLines(),
@@ -515,8 +515,9 @@
     `;
   }
 }
+
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-context-controls', GrContextControls);
 }
 
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-element.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-element.ts
index d907011..1452e0f 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-element.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-element.ts
@@ -350,7 +350,7 @@
   init() {
     this.cleanup();
     this.diffElement?.addEventListener(
-      'diff-context-expanded-internal',
+      'diff-context-expanded-internal-new',
       this.onDiffContextExpanded
     );
     this.builder?.init();
@@ -367,7 +367,7 @@
     this.processor?.cancel();
     this.builder?.cleanup();
     this.diffElement?.removeEventListener(
-      'diff-context-expanded-internal',
+      'diff-context-expanded-internal-new',
       this.onDiffContextExpanded
     );
   }
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-image.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-image.ts
index 400674d..eeb07d8 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-image.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder-image.ts
@@ -10,8 +10,8 @@
 import {html, LitElement, nothing} from 'lit';
 import {property, query, state} from 'lit/decorators.js';
 import {GrDiffBuilder} from './gr-diff-builder';
-import {createElementDiff, isNewDiff} from '../gr-diff/gr-diff-utils';
 import {GrDiffGroup} from '../gr-diff/gr-diff-group';
+import {isNewDiff, createElementDiff} from '../gr-diff/gr-diff-utils';
 
 // MIME types for images we allow showing. Do not include SVG, it can contain
 // arbitrary JavaScript.
@@ -45,6 +45,7 @@
   }
 
   private createImageDiffNew() {
+    // TODO(newdiff-cleanup): Remove cast when newdiff migration is complete.
     const imageDiff = document.createElement(
       'gr-diff-image-new'
     ) as GrDiffImageNew;
@@ -55,6 +56,7 @@
   }
 
   private createImageDiffOld() {
+    // TODO(newdiff-cleanup): Remove cast when newdiff migration is complete.
     const imageDiff = document.createElement(
       'gr-diff-image-old'
     ) as GrDiffImageOld;
@@ -267,7 +269,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-diff-image-new', GrDiffImageNew);
   customElements.define('gr-diff-image-old', GrDiffImageOld);
 }
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder.ts
index d826755..bcc54d4 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-builder.ts
@@ -34,7 +34,7 @@
 
 declare global {
   interface HTMLElementEventMap {
-    'diff-context-expanded-internal': CustomEvent<DiffContextExpandedEventDetail>;
+    'diff-context-expanded-internal-new': CustomEvent<DiffContextExpandedEventDetail>;
     'diff-context-expanded': CustomEvent<DiffContextExpandedExternalDetail>;
     'content-load-needed': CustomEvent<ContentLoadNeededEventDetail>;
   }
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-row.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-row.ts
index ae0a937..51024da 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-row.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-row.ts
@@ -470,7 +470,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-diff-row', GrDiffRow);
 }
 
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
index 97bec05..e02d62b 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
@@ -16,9 +16,9 @@
 } from '../../../api/diff';
 import {GrDiffGroup, GrDiffGroupType} from '../gr-diff/gr-diff-group';
 import {
+  isNewDiff,
   diffClasses,
   getResponsiveMode,
-  isNewDiff,
 } from '../gr-diff/gr-diff-utils';
 import {GrDiffRow} from './gr-diff-row';
 import '../gr-context-controls/gr-context-controls-section';
@@ -244,7 +244,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-diff-section', GrDiffSection);
 }
 
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
index 7c26ddc..2acedc8 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
@@ -6,7 +6,7 @@
 import {LitElement, html, TemplateResult} from 'lit';
 import {property} from 'lit/decorators.js';
 import {styleMap} from 'lit/directives/style-map.js';
-import {diffClasses, isNewDiff} from '../gr-diff/gr-diff-utils';
+import {isNewDiff, diffClasses} from '../gr-diff/gr-diff-utils';
 
 const SURROGATE_PAIR = /[\uD800-\uDBFF][\uDC00-\uDFFF]/;
 
@@ -145,7 +145,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-diff-text', GrDiffText);
 }
 
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-highlight/gr-annotation_test.ts b/polygerrit-ui/app/embed/diff/gr-diff-highlight/gr-annotation_test.ts
index f319a3c..3e1ce66 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-highlight/gr-annotation_test.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-highlight/gr-annotation_test.ts
@@ -3,7 +3,6 @@
  * Copyright 2016 Google LLC
  * SPDX-License-Identifier: Apache-2.0
  */
-
 import '../../../test/common-test-setup';
 import {GrAnnotation} from './gr-annotation';
 import {
diff --git a/polygerrit-ui/app/embed/diff/gr-diff/gr-diff.ts b/polygerrit-ui/app/embed/diff/gr-diff/gr-diff.ts
index 8c1a687..edd68dc 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff/gr-diff.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff/gr-diff.ts
@@ -25,7 +25,7 @@
   getResponsiveMode,
   isResponsive,
   isNewDiff,
-} from './gr-diff-utils';
+} from '../gr-diff/gr-diff-utils';
 import {BlameInfo, CommentRange, ImageInfo} from '../../../types/common';
 import {DiffInfo, DiffPreferencesInfo} from '../../../types/diff';
 import {
@@ -1110,7 +1110,7 @@
 }
 
 // TODO(newdiff-cleanup): Remove once newdiff migration is completed.
-if (!isNewDiff()) {
+if (isNewDiff()) {
   customElements.define('gr-diff', GrDiff);
 }
 
diff --git a/polygerrit-ui/web-test-runner.config.mjs b/polygerrit-ui/web-test-runner.config.mjs
index 01b1a91..bd8d9ac 100644
--- a/polygerrit-ui/web-test-runner.config.mjs
+++ b/polygerrit-ui/web-test-runner.config.mjs
@@ -26,7 +26,14 @@
 const config = {
   files: [
     "app/**/*_test.{ts,js}",
-    "!app/embed/diff-new/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-context-controls/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-builder/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-cursor/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-highlight/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-model/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-processor/**/*_test.{ts,js}",
+    "!app/embed/diff/gr-diff-selection/**/*_test.{ts,js}",
     "!**/node_modules/**/*",
     ...(process.argv.includes("--run-screenshots")
       ? []
@@ -37,7 +44,7 @@
     {
       name: "new-diff",
       files: [
-        "app/embed/diff-new/**/*_test.{ts,js}",
+        "app/embed/diff/**/*_test.{ts,js}",
         "app/elements/change/gr-file-list/gr-file-list_test.{ts,js}",
         "app/elements/diff/gr-apply-fix-dialog/gr-apply-fix-dialog_test.{ts,js}",
         "app/elements/diff/gr-diff-host/gr-diff-host_test.{ts,js}",