Improve saving models

src/Database/Models/DatabaseModel.php

@@ -177,17 +177,17 @@ public function save(TransactionManager|null $transactionManager = null): bool
         $result = $queryBuilder
             ->insertGetId($data, $this->getModelKeyColumnName());
 
-        if ($result) {
-            if (! $this->keyIsInitialized()) {
-                $this->{$this->getModelKeyName()} = $result;
-            }
-
-            $this->setAsExisting();
+        if ($result === false) {
+            return false;
+        }
 
-            return true;
+        if (! $this->keyIsInitialized() && $result !== null) {
+            $this->{$this->getModelKeyName()} = $result;
         }
 
-        return false;
+        $this->setAsExisting();
+
+        return true;
     }
 
     public function delete(TransactionManager|null $transactionManager = null): bool

src/Database/Models/QueryBuilders/DatabaseQueryBuilder.php

@@ -204,12 +204,12 @@ public function create(array $attributes): DatabaseModel
 
         $queryBuilder = clone $this;
         $queryBuilder->setModel($model);
+        $modelKeyName = $model->getModelKeyName();
+        $keyWasInitialized = isset($model->{$modelKeyName});
         $result = $queryBuilder->insertGetId($data, $model->getModelKeyColumnName());
 
-        if ($result) {
-            $modelKeyName = $model->getModelKeyName();
-
-            if (! isset($model->{$modelKeyName})) {
+        if ($result !== false && ($keyWasInitialized || $result !== null)) {
+            if (! $keyWasInitialized) {
                 $model->{$modelKeyName} = $result;
             }
 

tests/Feature/Database/DatabaseModelTest.php

@@ -783,6 +783,34 @@
     expect($model->createdAt)->toBeInstanceOf(Date::class);
 });
 
+it('creates model with manually assigned string ID when insertGetId returns zero', function () {
+    $insertResult = new Result([['Query OK']]);
+    $insertResult->setLastInsertedId(0);
+
+    $connection = $this->getMockBuilder(MysqlConnectionPool::class)->getMock();
+
+    $connection->expects($this->exactly(1))
+        ->method('prepare')
+        ->willReturnOnConsecutiveCalls(
+            new Statement($insertResult),
+        );
+
+    $this->app->swap(Connection::default(), $connection);
+
+    $uuid = Str::uuid()->toString();
+
+    $model = UserWithUuid::create([
+        'id' => $uuid,
+        'name' => 'John Doe',
+        'email' => faker()->email(),
+        'created_at' => Date::now(),
+    ]);
+
+    expect($model->isExisting())->toBeTrue();
+    expect($model->id)->toBe($uuid);
+    expect($model->createdAt)->toBeInstanceOf(Date::class);
+});
+
 it('throws an exception when column in invalid on create instance', function () {
     expect(function () {
         $connection = $this->getMockBuilder(MysqlConnectionPool::class)->getMock();
@@ -895,6 +923,33 @@
     expect($model->createdAt)->toBeInstanceOf(Date::class);
 });
 
+it('saves a new model with manually assigned string ID when insertGetId returns zero', function () {
+    $insertResult = new Result([['Query OK']]);
+    $insertResult->setLastInsertedId(0);
+
+    $connection = $this->getMockBuilder(MysqlConnectionPool::class)->getMock();
+
+    $connection->expects($this->exactly(1))
+        ->method('prepare')
+        ->willReturnOnConsecutiveCalls(
+            new Statement($insertResult),
+        );
+
+    $this->app->swap(Connection::default(), $connection);
+
+    $uuid = Str::uuid()->toString();
+    $model = new UserWithUuid();
+    $model->id = $uuid;
+    $model->name = 'John Doe';
+    $model->email = faker()->email();
+
+    expect($model->isExisting())->toBeFalse();
+    expect($model->save())->toBeTrue();
+    expect($model->isExisting())->toBeTrue();
+    expect($model->id)->toBe($uuid);
+    expect($model->createdAt)->toBeInstanceOf(Date::class);
+});
+
 it('updates an existing model with string ID correctly', function () {
     $uuid = Str::uuid()->toString();
     $data = [