diff --git a/Modules/Exercise01/Tests/Feature/Http/Controllers/OrderControllerTest.php b/Modules/Exercise01/Tests/Feature/Http/Controllers/OrderControllerTest.php
new file mode 100644
index 0000000..35bd519
--- /dev/null
+++ b/Modules/Exercise01/Tests/Feature/Http/Controllers/OrderControllerTest.php
@@ -0,0 +1,144 @@
+<?php
+
+namespace Modules\Exercise01\Tests\Feature\Http\Controllers;
+
+use Tests\TestCase;
+use Modules\Exercise01\Http\Controllers\OrderController;
+use Modules\Exercise01\Models\Voucher;
+use Modules\Exercise01\Services\DTO\Price;
+use Modules\Exercise01\Services\PriceService;
+use Tests\SetupDatabaseTrait;
+
+class OrderControllerTest extends TestCase
+{
+    use SetupDatabaseTrait;
+
+    protected $priceServiceMock;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        // Laravel helper: mock and bind to service container
+        $this->priceServiceMock = $this->mock(PriceService::class);
+    }
+
+    function test_it_show_form_order()
+    {
+        $url = action([OrderController::class, 'showForm']);
+
+        $response = $this->get($url);
+
+        $response->assertViewIs('exercise01::order');
+        $response->assertViewHasAll([
+            'unitPrice',
+            'voucherUnitPrice',
+            'specialTimeUnitPrice',
+            'specialTimePeriod',
+        ]);
+        $response->assertSessionMissing('order');
+    }
+
+    private function inValidInputs($inputs)
+    {
+        $validInputs = [
+            'quantity' => 1,
+            'voucher' => null,
+        ];
+
+        return array_filter(array_merge($validInputs, $inputs), function ($value) {
+            return $value !== null;
+        });
+    }
+
+    /**
+     * @dataProvider provideWrongQuantity
+     * @dataProvider provideWrongVoucher
+     */
+    function test_it_show_error_when_input_invalid($inputKey, $inputValue)
+    {
+        $url = action([OrderController::class, 'create']);
+        $inputs = $this->inValidInputs([
+            $inputKey => is_callable($inputValue) ? $inputValue() : $inputValue,
+        ]);
+
+        $response = $this->post($url, $inputs);
+
+        $response->assertSessionHasErrors([$inputKey]);
+    }
+
+    function provideWrongQuantity()
+    {
+        return [
+            'Quantity is required' => ['quantity', null],
+            'Quantity should be integer' => ['quantity', 1.1],
+            'Quantity should be greater than 1' => ['quantity', 0],
+        ];
+    }
+
+    function provideWrongVoucher()
+    {
+        return [
+            'Voucher must exist' => ['voucher', 'this-voucher-not-exist'],
+            'Voucher must be active' => [
+                'voucher',
+                function () {
+                    Voucher::factory()->inactive()->create(['code' => 'existed-voucher-but-inactive']);
+
+                    return 'existed-voucher-but-inactive';
+                },
+            ],
+        ];
+    }
+
+    /**
+     * @dataProvider provideEmptyVoucher
+     */
+    function test_it_should_not_error_when_input_empty_voucher($voucher)
+    {
+        $url = action([OrderController::class, 'create']);
+        $dummyPrice = new Price(100, 0, 0);
+        $this->priceServiceMock
+            ->shouldReceive('calculate')
+            ->andReturn($dummyPrice);
+
+        $response = $this->post($url, [
+            'quantity' => 1,
+            'voucher' => $voucher,
+        ]);
+
+        $response->assertSessionDoesntHaveErrors(['voucher']);
+    }
+
+    function provideEmptyVoucher()
+    {
+        return [
+            'Voucher can be null' => [null],
+            'Voucher can be empty string' => [''],
+            'Voucher can be string with spaces only' => ['   '],
+        ];
+    }
+
+    function test_it_create_order_when_input_valid_quantity_and_voucher_code()
+    {
+        Voucher::factory()->active()->create(['code' => 'existed-voucher']);
+        $dummyPrice = new Price(100, 0, 0);
+        $this->priceServiceMock
+            ->shouldReceive('calculate')
+            ->andReturn($dummyPrice);
+
+        $url = action([OrderController::class, 'create']);
+
+        $response = $this->post($url, [
+            'quantity' => 1,
+            'voucher' => 'existed-voucher',
+        ]);
+
+        $response->assertSessionDoesntHaveErrors(['quantity']);
+        $response->assertSessionDoesntHaveErrors(['voucher']);
+        $response->assertSessionHasInput(['quantity', 'voucher']);
+        $response->assertSessionHas('order', function ($order) {
+            return $order['quantity'] == 1 && $order['price'] instanceof Price;
+        });
+    }
+}
diff --git a/infection.json b/infection.json
index e93241b..8d8b3de 100644
--- a/infection.json
+++ b/infection.json
@@ -1,7 +1,11 @@
 {
     "source": {
         "directories": [
-            "Modules/"
+            "Modules/Exercise01/",
+            "Modules/Exercise03/",
+            "Modules/Exercise04/",
+            "Modules/Exercise05/",
+            "Modules/Exercise07/"
         ],
         "excludes": [
             "Config",
diff --git a/phpunit.xml b/phpunit.xml
index 77442f0..6be7968 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -6,9 +6,11 @@
 >
     <testsuites>
         <testsuite name="All">
-            <directory suffix="Test.php">./tests/Unit</directory>
-            <directory suffix="Test.php">./tests/Feature</directory>
-            <directory suffix="Test.php">./Modules/**/Tests</directory>
+            <directory suffix="Test.php">./Modules/Exercise01/Tests</directory>
+            <directory suffix="Test.php">./Modules/Exercise03/Tests</directory>
+            <directory suffix="Test.php">./Modules/Exercise04/Tests</directory>
+            <directory suffix="Test.php">./Modules/Exercise05/Tests</directory>
+            <directory suffix="Test.php">./Modules/Exercise07/Tests</directory>
         </testsuite>
         <testsuite name="Exercise01">
             <directory suffix="Test.php">./Modules/Exercise01/Tests</directory>
@@ -43,8 +45,11 @@
     </testsuites>
     <coverage processUncoveredFiles="true">
         <include>
-            <directory suffix=".php">./app</directory>
-            <directory suffix=".php">./Modules</directory>
+            <directory suffix=".php">./Modules/Exercise01</directory>
+            <directory suffix=".php">./Modules/Exercise03</directory>
+            <directory suffix=".php">./Modules/Exercise04</directory>
+            <directory suffix=".php">./Modules/Exercise05</directory>
+            <directory suffix=".php">./Modules/Exercise07</directory>
         </include>
         <exclude>
             <directory>./Modules/**/Config</directory>