fix(utils): handle undefined in html util functions

this prevents displaying abstract 'undefined' as string in record-preview (although abstract should usually not be undefined)

libs/util/shared/src/lib/utils/remove-whitespace.spec.ts

@@ -1,6 +1,10 @@
 import { removeWhitespace } from './remove-whitespace'
 
 describe('#removeWhitespace', () => {
+  it('returns undefined input is not defined', () => {
+    const html = null
+    expect(removeWhitespace(html)).toBe(undefined)
+  })
   it('removes superfluent whitespace for a single word', () => {
     const html = ' hello '
     expect(removeWhitespace(html)).toBe('hello')

libs/util/shared/src/lib/utils/remove-whitespace.ts

@@ -1,3 +1,3 @@
 export const removeWhitespace = function (str: string): string {
-  return str.replace(/\s+/g, ' ').trim()
+  return str ? str.replace(/\s+/g, ' ').trim() : undefined
 }

libs/util/shared/src/lib/utils/strip-html.spec.ts

@@ -7,6 +7,12 @@ describe('strip HTML', () => {
       expect(stripHtml(html)).toBe('hello')
     })
   })
+  describe('when HTML not defined', () => {
+    it('returns undefined', () => {
+      const html = null
+      expect(stripHtml(html)).toBe(undefined)
+    })
+  })
   describe('when no HTML tags', () => {
     it('return same string', () => {
       const html = 'hello'

libs/util/shared/src/lib/utils/strip-html.ts

@@ -1,4 +1,5 @@
 export const stripHtml = function (html: string): string {
+  if (!html) return undefined
   const doc = new DOMParser().parseFromString(html, 'text/html')
   return doc.body.textContent || ''
 }