Fix support for diffing deltas with blanks

Author: pmachapman

src/SIL.XForge.Scripture/ClientApp/src/app/translate/editor/editor-history/editor-history.service.spec.ts

@@ -34,6 +34,12 @@ describe('EditorHistoryService', () => {
     expect(obj.subObj).toBeNull();
   });
 
+  it('should remove blanks', () => {
+    const delta = new Delta().insert('Hello ').insert({ blank: true }).insert({ blank: false }).insert('World');
+    const result = service.removeBlanks(delta);
+    expect(result).toEqual(new Delta().insert('Hello World'));
+  });
+
   describe('formatTimestamp', () => {
     it('should return "Invalid Date" if timestamp is null or empty', () => {
       expect(service.formatTimestamp(null)).toBe('Invalid Date');

src/SIL.XForge.Scripture/ClientApp/src/app/translate/editor/editor-history/editor-history.service.ts

@@ -1,5 +1,7 @@
 import { Injectable } from '@angular/core';
+import { cloneDeep } from 'lodash-es';
 import { Delta } from 'quill';
+import { DeltaOperation } from 'rich-text';
 import { I18nService } from 'xforge-common/i18n.service';
 
 const MILLISECONDS_IN_A_DAY = 24 * 60 * 60 * 1000;
@@ -42,6 +44,10 @@ export class EditorHistoryService {
     deltaA.forEach(obj => this.removeCid(obj));
     deltaB.forEach(obj => this.removeCid(obj));
 
+    // Remove the blanks from the deltas
+    deltaA = this.removeBlanks(deltaA);
+    deltaB = this.removeBlanks(deltaB);
+
     const diff: Delta = deltaA.diff(deltaB);
 
     // Process each op in the diff
@@ -70,4 +76,19 @@ export class EditorHistoryService {
       if (typeof obj[subObj] === 'object' && obj[subObj] != null) this.removeCid(obj[subObj]);
     }
   }
+
+  removeBlanks(modelDelta: Delta): Delta {
+    if (modelDelta.ops == null || modelDelta.ops.length < 1) {
+      return new Delta();
+    }
+    const adjustedDelta = new Delta();
+    for (const op of modelDelta.ops) {
+      const cloneOp: DeltaOperation | undefined = cloneDeep(op);
+      if (!(cloneOp.insert != null && cloneOp.insert['blank'] != null)) {
+        (adjustedDelta as any).push(cloneOp);
+      }
+    }
+
+    return adjustedDelta;
+  }
 }