feat: add contact filter to search by name

src/app/pipes/contacts-filter-pipe.spec.ts

@@ -0,0 +1,32 @@
+import { pipe } from 'rxjs';
+import { ContactsFilterPipe } from './contacts-filter-pipe';
+import { ContactDTO } from '../models/ContactDTO';
+
+describe('ContactsFilterPipe', () => {
+  let pipe: ContactsFilterPipe;
+  let CONTACTS_MOCK = [
+    new ContactDTO(1,'mock')
+  ];
+
+  beforeEach(() => {
+    pipe = new ContactsFilterPipe();
+  });
+
+  it('create an instance', () => {
+    expect(pipe).toBeTruthy();
+  });
+
+  it('should return an empty array if value is null', () => {
+    expect(pipe.transform(null, '')).toEqual([]);
+  });
+
+  it('should return the passed array without transformation if name is empty (\'\')', () => {
+    expect(pipe.transform(CONTACTS_MOCK, '')).toEqual(CONTACTS_MOCK);
+  });
+
+  it('should return entries wich name contains the given string name', () => {
+    const ARG_MOCK = 'mo';
+    const transformationResult = pipe.transform(CONTACTS_MOCK, ARG_MOCK);
+    expect(transformationResult.find( c => c.name.includes(ARG_MOCK))).toBeTruthy();
+  });
+});

src/app/pipes/contacts-filter-pipe.ts

@@ -0,0 +1,15 @@
+import { Pipe, PipeTransform } from '@angular/core';
+import { ContactDTO } from '../models/ContactDTO';
+
+@Pipe({
+  name: 'contactsFilter'
+})
+export class ContactsFilterPipe implements PipeTransform {
+
+  transform(value: ContactDTO[]|null, name: string): ContactDTO[] {
+    if(value === null) return [];
+    if(name === '') return value;
+    return value.filter( contact => contact.name.toLowerCase().includes(name.toLowerCase()));
+  }
+
+}