handle entries with no creator users

packages/core/admin/admin/src/content-manager/utils/getDisplayName.js

@@ -6,9 +6,15 @@
  * @property {string} username
  * @property {string} email
  *
- * @type {(user: AdminUserNamesAttributes, formatMessage: import('react-intl').formatMessage) => string}
+ * @type {(user: AdminUserNamesAttributes | null, formatMessage: import('react-intl').formatMessage) => string}
  */
-const getDisplayName = ({ firstname, lastname, username, email }, formatMessage) => {
+const getDisplayName = (user, formatMessage) => {
+  if (!user) {
+    return '-';
+  }
+
+  const { firstname, lastname, username, email } = user;
+
   if (username) {
     return username;
   }

packages/core/admin/admin/src/content-manager/utils/tests/getDisplayName.test.js

@@ -0,0 +1,49 @@
+import { getDisplayName } from '../getDisplayName';
+
+const mockFormatMessage = jest.fn((message, values) => {
+  return `${values.firstname} ${values.lastname}`;
+});
+
+describe('getDisplayName', () => {
+  it('should return username if username is defined', () => {
+    expect(
+      getDisplayName(
+        {
+          username: 'johnDoe',
+          firstname: 'John',
+          lastname: 'Doe',
+          email: 'john@doe.com',
+        },
+        mockFormatMessage
+      )
+    ).toEqual('johnDoe');
+  });
+
+  it('should return firstname and lastname if firstname is defined', () => {
+    expect(
+      getDisplayName(
+        {
+          firstname: 'John',
+          lastname: 'Doe',
+          email: 'john@doe.com',
+        },
+        mockFormatMessage
+      )
+    ).toEqual('John Doe');
+  });
+
+  it('should return email if username and firstname are not defined', () => {
+    expect(
+      getDisplayName(
+        {
+          email: 'john@doe.com',
+        },
+        mockFormatMessage
+      )
+    ).toEqual('john@doe.com');
+  });
+
+  it('should return a dash if user is null', () => {
+    expect(getDisplayName(null, mockFormatMessage)).toEqual('-');
+  });
+});