diff --git a/composer.json b/composer.json
index d1ed748..b6da739 100644
--- a/composer.json
+++ b/composer.json
@@ -22,11 +22,11 @@
     },
     "require-dev": {
         "roave/security-advisories": "dev-latest",
-        "wp-cli/wp-cli-tests": "^4"
+        "wp-cli/wp-cli-tests": "^5"
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "0.11.x-dev"
+            "dev-master": "0.12.x-dev"
         }
     },
     "minimum-stability": "dev",
@@ -42,7 +42,8 @@
     "config": {
         "allow-plugins": {
             "dealerdirect/phpcodesniffer-composer-installer": true,
-            "johnpbloch/wordpress-core-installer": true
+            "johnpbloch/wordpress-core-installer": true,
+            "phpstan/extension-installer": true
         }
     },
     "scripts": {
@@ -50,11 +51,13 @@
         "behat-rerun": "rerun-behat-tests",
         "lint": "run-linter-tests",
         "phpcs": "run-phpcs-tests",
+        "phpstan": "run-phpstan-tests",
         "phpunit": "run-php-unit-tests",
         "prepare-tests": "install-package-tests",
         "test": [
             "@lint",
             "@phpcs",
+            "@phpstan",
             "@phpunit",
             "@behat"
         ]
diff --git a/tests/Test_Arguments.php b/tests/Test_Arguments.php
index 9f89eda..2201849 100644
--- a/tests/Test_Arguments.php
+++ b/tests/Test_Arguments.php
@@ -1,6 +1,6 @@
 <?php
 
-use cli\Arguments;
+use PHPUnit\Framework\Attributes\DataProvider;
 use WP_CLI\Tests\TestCase;
 
 /**
@@ -255,6 +255,7 @@ private function _testParse($cliParams, $expectedValues)
      *
      * @dataProvider settingsWithValidOptions
      */
+	#[DataProvider( 'settingsWithValidOptions' )] // phpcs:ignore PHPCompatibility.Attributes.NewAttributes.PHPUnitAttributeFound
     public function testParseWithValidOptions($cliParams, $expectedValues)
     {
         $this->_testParse($cliParams, $expectedValues);
@@ -265,6 +266,7 @@ public function testParseWithValidOptions($cliParams, $expectedValues)
      * @param  array $expectedValues expected values after parsing
      * @dataProvider settingsWithMissingOptions
      */
+	#[DataProvider( 'settingsWithMissingOptions' )] // phpcs:ignore PHPCompatibility.Attributes.NewAttributes.PHPUnitAttributeFound
     public function testParseWithMissingOptions($cliParams, $expectedValues)
     {
         $this->expectException(\Exception::class);
@@ -277,6 +279,7 @@ public function testParseWithMissingOptions($cliParams, $expectedValues)
      * @param  array $expectedValues expected values after parsing
      * @dataProvider settingsWithMissingOptionsWithDefault
      */
+	#[DataProvider( 'settingsWithMissingOptionsWithDefault' )] // phpcs:ignore PHPCompatibility.Attributes.NewAttributes.PHPUnitAttributeFound
     public function testParseWithMissingOptionsWithDefault($cliParams, $expectedValues)
     {
         $this->_testParse($cliParams, $expectedValues);
@@ -287,6 +290,7 @@ public function testParseWithMissingOptionsWithDefault($cliParams, $expectedValu
      * @param  array $expectedValues expected values after parsing
      * @dataProvider settingsWithNoOptionsWithDefault
      */
+	#[DataProvider( 'settingsWithNoOptionsWithDefault' )] // phpcs:ignore PHPCompatibility.Attributes.NewAttributes.PHPUnitAttributeFound
     public function testParseWithNoOptionsWithDefault($cliParams, $expectedValues) {
         $this->_testParse($cliParams, $expectedValues);
     }
diff --git a/tests/Test_Colors.php b/tests/Test_Colors.php
index bac23a4..b7d28ff 100644
--- a/tests/Test_Colors.php
+++ b/tests/Test_Colors.php
@@ -2,12 +2,14 @@
 
 use cli\Colors;
 use WP_CLI\Tests\TestCase;
+use PHPUnit\Framework\Attributes\DataProvider;
 
 class Test_Colors extends TestCase {
 
 	/**
      * @dataProvider dataColors
 	 */
+	#[DataProvider( 'dataColors' )] // phpcs:ignore PHPCompatibility.Attributes.NewAttributes.PHPUnitAttributeFound
 	public function testColors( $str, $color ) {
 		// Colors enabled.
 		Colors::enable( true );