add test

app/Models/User.php

@@ -76,13 +76,23 @@ class User extends Authenticatable implements MustVerifyEmail
     public function follow(User|int $user): void
     {
         $userId = $user instanceof User ? $user->id : $user;
+
+        if ($this->id === $userId) {
+            // don't allow following yourself
+            return;
+        }
+
         $this->following()->syncWithoutDetaching($userId);
     }
 
     public function unfollow(User|int $user): void
     {
         $userId = $user instanceof User ? $user->id : $user;
-        $this->following()->detach($userId);
+
+        // make sure the user is being followed before trying to detach
+        if ($this->isFollowing($userId)) {
+            $this->following()->detach($userId);
+        }
     }
 
     /**

tests/Feature/User/FollowTest.php

@@ -0,0 +1,100 @@
+<?php
+
+use App\Models\User;
+
+test('confirm a user cannot follow themself', function () {
+    $user = User::factory()->create();
+
+    $user->follow($user);
+
+    $this->assertEmpty($user->follwers);
+    $this->assertEmpty($user->following);
+});
+
+test('confirm a user can follow and unfollow another user', function () {
+    $user1 = User::factory()->create();
+    $user2 = User::factory()->create();
+
+    $user1->follow($user2);
+
+    $this->assertTrue($user1->isFollowing($user2));
+
+    $user1->unfollow($user2);
+
+    $this->assertFalse($user1->isFollowing($user2));
+});
+
+test('confirm following a user cannot be done twice', function () {
+    $user1 = User::factory()->create();
+    $user2 = User::factory()->create();
+
+    $user1->follow($user2);
+    $user1->follow($user2);
+
+
+    $this->assertCount(1, $user1->following);
+    $this->assertCount(1, $user2->followers);
+});
+
+test('confirm unfollowing a user that isnt being followed doesnt throw', function () {
+    $user1 = User::factory()->create();
+    $user2 = User::factory()->create();
+
+    $user1->unfollow($user2);
+
+    $this->assertEmpty($user1->following);
+    $this->assertEmpty($user2->followers);
+});
+
+test('confirm unfollowing random number doesnt perform detach all', function () {
+    $user1 = User::factory()->create();
+    $user2 = User::factory()->create();
+    $user3 = User::factory()->create();
+
+    $user1->follow($user2);
+    $user1->follow($user3);
+
+    $this->assertTrue($user1->isFollowing($user2));
+    $this->assertTrue($user1->isFollowing($user3));
+
+    $this->assertCount(2, $user1->following);
+    $this->assertCount(1, $user2->followers);
+    $this->assertCount(1, $user3->followers);
+
+    $user1->unfollow(111112222233333);
+
+    $this->assertTrue($user1->isFollowing($user2));
+    $this->assertTrue($user1->isFollowing($user3));
+});
+
+test('confirm null follow input fails', function () {
+    $this->expectException(TypeError::class);
+
+    $user = User::factory()->create();
+
+    $user->follow(null);
+});
+
+test('confirm empty follow input fails', function () {
+    $this->expectException(ArgumentCountError::class);
+
+    $user = User::factory()->create();
+
+    $user->follow();
+});
+
+test('confirm null unfollow input fails', function () {
+    $this->expectException(TypeError::class);
+
+    $user = User::factory()->create();
+
+    $user->unfollow(null);
+});
+
+test('confirm empty unfollow input fails', function () {
+    $this->expectException(ArgumentCountError::class);
+
+    $user = User::factory()->create();
+
+    $user->unfollow();
+});