diff --git a/tests/phpunit/tests/ajax/CustomizeManager.php b/tests/phpunit/tests/ajax/CustomizeManager.php
index 581316e09b10..ca8bd74a370a 100644
--- a/tests/phpunit/tests/ajax/CustomizeManager.php
+++ b/tests/phpunit/tests/ajax/CustomizeManager.php
@@ -286,7 +286,7 @@ function test_save_success_publish_create() {
 		);
 		$this->make_ajax_call( 'customize_save' );
 		$this->assertTrue( $this->_last_response_parsed['success'] );
-		$this->assertInternalType( 'array', $this->_last_response_parsed['data'] );
+		$this->assertIsArray( $this->_last_response_parsed['data'] );
 
 		$this->assertEquals( 'publish', $this->_last_response_parsed['data']['changeset_status'] );
 		$this->assertArrayHasKey( 'next_changeset_uuid', $this->_last_response_parsed['data'] );
@@ -325,7 +325,7 @@ function test_save_success_publish_edit() {
 		$_POST['customize_changeset_title']  = 'Published';
 		$this->make_ajax_call( 'customize_save' );
 		$this->assertTrue( $this->_last_response_parsed['success'] );
-		$this->assertInternalType( 'array', $this->_last_response_parsed['data'] );
+		$this->assertIsArray( $this->_last_response_parsed['data'] );
 
 		$this->assertEquals( 'publish', $this->_last_response_parsed['data']['changeset_status'] );
 		$this->assertArrayHasKey( 'next_changeset_uuid', $this->_last_response_parsed['data'] );
diff --git a/tests/phpunit/tests/comment/query.php b/tests/phpunit/tests/comment/query.php
index d7a50b52e66c..23f76c1294eb 100644
--- a/tests/phpunit/tests/comment/query.php
+++ b/tests/phpunit/tests/comment/query.php
@@ -3332,9 +3332,9 @@ public function test_comment_query_object() {
 		$this->assertNull( $query1->query_vars );
 		$this->assertEmpty( $query1->comments );
 		$comments = $query1->query( array( 'status' => 'all' ) );
-		$this->assertInternalType( 'array', $query1->query_vars );
+		$this->assertIsArray( $query1->query_vars );
 		$this->assertNotEmpty( $query1->comments );
-		$this->assertInternalType( 'array', $query1->comments );
+		$this->assertIsArray( $query1->comments );
 
 		$query2 = new WP_Comment_Query( array( 'status' => 'all' ) );
 		$this->assertNotEmpty( $query2->query_vars );
diff --git a/tests/phpunit/tests/customize/custom-css-setting.php b/tests/phpunit/tests/customize/custom-css-setting.php
index 0734a0b12079..bd7244918943 100644
--- a/tests/phpunit/tests/customize/custom-css-setting.php
+++ b/tests/phpunit/tests/customize/custom-css-setting.php
@@ -344,10 +344,10 @@ function test_update_filter() {
 	 * @return array Data.
 	 */
 	function filter_update_custom_css_data( $data, $args ) {
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertEqualSets( array( 'css', 'preprocessed' ), array_keys( $data ) );
 		$this->assertEquals( '', $data['preprocessed'] );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->assertEqualSets( array( 'css', 'preprocessed', 'stylesheet' ), array_keys( $args ) );
 		$this->assertEquals( $args['css'], $data['css'] );
 		$this->assertEquals( $args['preprocessed'], $data['preprocessed'] );
diff --git a/tests/phpunit/tests/customize/manager.php b/tests/phpunit/tests/customize/manager.php
index 6bb2525ea845..2b6fa4fac4e5 100644
--- a/tests/phpunit/tests/customize/manager.php
+++ b/tests/phpunit/tests/customize/manager.php
@@ -677,9 +677,9 @@ function test_import_theme_starter_content() {
 		$this->assertEqualSets( $expected_setting_ids, array_keys( $changeset_values ) );
 
 		foreach ( array( 'widget_text[2]', 'widget_meta[3]' ) as $setting_id ) {
-			$this->assertInternalType( 'array', $changeset_values[ $setting_id ] );
+			$this->assertIsArray( $changeset_values[ $setting_id ] );
 			$instance_data = $wp_customize->widgets->sanitize_widget_instance( $changeset_values[ $setting_id ] );
-			$this->assertInternalType( 'array', $instance_data );
+			$this->assertIsArray( $instance_data );
 			$this->assertArrayHasKey( 'title', $instance_data );
 		}
 
@@ -787,7 +787,7 @@ function test_import_theme_starter_content() {
 		$this->assertEquals( 'auto-draft', get_post( $posts_by_name['waffles'] )->post_status );
 		$this->assertNotEquals( $changeset_data['blogname']['value'], get_option( 'blogname' ) );
 		$r = $wp_customize->save_changeset_post( array( 'status' => 'publish' ) );
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertEquals( 'publish', get_post( $posts_by_name['about'] )->post_status );
 		$this->assertEquals( 'inherit', get_post( $posts_by_name['waffles'] )->post_status );
 		$this->assertEquals( $changeset_data['blogname']['value'], get_option( 'blogname' ) );
@@ -1041,7 +1041,7 @@ function test_save_changeset_post_without_theme_activation() {
 				'data'     => $pre_saved_data,
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 
 		$this->assertEquals( $did_action['customize_save_validation_before'] + 1, did_action( 'customize_save_validation_before' ) );
 
@@ -1098,7 +1098,7 @@ function test_save_changeset_post_without_theme_activation() {
 		);
 		$this->assertInstanceOf( 'WP_Error', $r );
 		$this->assertEquals( 'transaction_fail', $r->get_error_code() );
-		$this->assertInternalType( 'array', $r->get_error_data() );
+		$this->assertIsArray( $r->get_error_data() );
 		$this->assertArrayHasKey( 'setting_validities', $r->get_error_data() );
 		$error_data = $r->get_error_data();
 		$this->assertArrayHasKey( 'blogname', $error_data['setting_validities'] );
@@ -1137,7 +1137,7 @@ function test_save_changeset_post_without_theme_activation() {
 				),
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertArrayHasKey( 'setting_validities', $r );
 		$this->assertTrue( $r['setting_validities']['blogname'] );
 		$this->assertInstanceOf( 'WP_Error', $r['setting_validities']['bar_unknown'] );
@@ -1204,7 +1204,7 @@ function test_save_changeset_post_without_theme_activation() {
 				),
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertEquals( 'Do it live \o/', get_option( 'blogname' ) );
 		$this->assertEquals( 'trash', get_post_status( $post_id ) ); // Auto-trashed.
 		$this->assertEquals( $original_capabilities, wp_list_pluck( $manager->settings(), 'capability' ) );
@@ -1421,8 +1421,8 @@ public function filter_map_meta_cap_to_disallow_unfiltered_html( $caps, $cap ) {
 	 */
 	function filter_customize_changeset_save_data( $data, $context ) {
 		$this->customize_changeset_save_data_call_count += 1;
-		$this->assertInternalType( 'array', $data );
-		$this->assertInternalType( 'array', $context );
+		$this->assertIsArray( $data );
+		$this->assertIsArray( $context );
 		$this->assertArrayHasKey( 'uuid', $context );
 		$this->assertArrayHasKey( 'title', $context );
 		$this->assertArrayHasKey( 'status', $context );
@@ -1512,7 +1512,7 @@ function test_save_changeset_post_with_varying_users() {
 				),
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertEquals(
 			array_fill_keys( array( 'blogname', 'scratchpad', 'background_color' ), true ),
 			$r['setting_validities']
@@ -1539,7 +1539,7 @@ function test_save_changeset_post_with_varying_users() {
 				),
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertEquals(
 			array_fill_keys( array( 'blogname', 'background_color' ), true ),
 			$r['setting_validities']
@@ -1568,7 +1568,7 @@ function test_save_changeset_post_with_varying_users() {
 				'user_id' => self::$subscriber_user_id,
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 		$this->assertEquals(
 			array_fill_keys( array( 'scratchpad', 'blogname' ), true ),
 			$r['setting_validities']
@@ -1887,7 +1887,7 @@ public function test_save_changeset_post_with_autosave() {
 				'autosave' => true,
 			)
 		);
-		$this->assertInternalType( 'array', $r );
+		$this->assertIsArray( $r );
 
 		// Verify that autosave happened.
 		$autosave_revision = wp_get_post_autosave( $changeset_post_id, get_current_user_id() );
@@ -2714,10 +2714,10 @@ function test_prepare_setting_validity_for_js() {
 		$error->add( 'bad_letter', 'Bad letra', 123 );
 		$error->add( 'bad_number', 'Bad number', array( 'number' => 123 ) );
 		$validity = $this->manager->prepare_setting_validity_for_js( $error );
-		$this->assertInternalType( 'array', $validity );
+		$this->assertIsArray( $validity );
 		foreach ( $error->errors as $code => $messages ) {
 			$this->assertArrayHasKey( $code, $validity );
-			$this->assertInternalType( 'array', $validity[ $code ] );
+			$this->assertIsArray( $validity[ $code ] );
 			$this->assertEquals( join( ' ', $messages ), $validity[ $code ]['message'] );
 			$this->assertArrayHasKey( 'data', $validity[ $code ] );
 			$this->assertEquals( $validity[ $code ]['data'], $error->get_error_data( $code ) );
@@ -2927,7 +2927,7 @@ function filter_customize_dynamic_setting_args_for_test_dynamic_settings( $setti
 	function filter_customize_dynamic_setting_class_for_test_dynamic_settings( $setting_class, $setting_id, $setting_args ) {
 		$this->assertEquals( 'WP_Customize_Setting', $setting_class );
 		$this->assertInternalType( 'string', $setting_id );
-		$this->assertInternalType( 'array', $setting_args );
+		$this->assertIsArray( $setting_args );
 		return $setting_class;
 	}
 
@@ -3038,7 +3038,7 @@ function test_autofocus() {
 	 */
 	function test_nonces() {
 		$nonces = $this->manager->get_nonces();
-		$this->assertInternalType( 'array', $nonces );
+		$this->assertIsArray( $nonces );
 		$this->assertArrayHasKey( 'save', $nonces );
 		$this->assertArrayHasKey( 'preview', $nonces );
 
@@ -3202,10 +3202,10 @@ function test_customize_loaded_components_filter() {
 	 * @return array Components.
 	 */
 	function return_array_containing_widgets( $components, $customize_manager ) {
-		$this->assertInternalType( 'array', $components );
+		$this->assertIsArray( $components );
 		$this->assertContains( 'widgets', $components );
 		$this->assertContains( 'nav_menus', $components );
-		$this->assertInternalType( 'array', $components );
+		$this->assertIsArray( $components );
 		$this->assertInstanceOf( 'WP_Customize_Manager', $customize_manager );
 		return array( 'widgets' );
 	}
@@ -3219,10 +3219,10 @@ function return_array_containing_widgets( $components, $customize_manager ) {
 	 * @return array Components.
 	 */
 	function return_array_containing_nav_menus( $components, $customize_manager ) {
-		$this->assertInternalType( 'array', $components );
+		$this->assertIsArray( $components );
 		$this->assertContains( 'widgets', $components );
 		$this->assertContains( 'nav_menus', $components );
-		$this->assertInternalType( 'array', $components );
+		$this->assertIsArray( $components );
 		$this->assertInstanceOf( 'WP_Customize_Manager', $customize_manager );
 		return array( 'nav_menus' );
 	}
diff --git a/tests/phpunit/tests/customize/nav-menu-item-setting.php b/tests/phpunit/tests/customize/nav-menu-item-setting.php
index 5f581ff0102e..a066d24ee128 100644
--- a/tests/phpunit/tests/customize/nav-menu-item-setting.php
+++ b/tests/phpunit/tests/customize/nav-menu-item-setting.php
@@ -73,7 +73,7 @@ function test_construct() {
 		$this->assertNull( $setting->previous_post_id );
 		$this->assertNull( $setting->update_status );
 		$this->assertNull( $setting->update_error );
-		$this->assertInternalType( 'array', $setting->default );
+		$this->assertIsArray( $setting->default );
 
 		$default = array(
 			'object_id'        => 0,
@@ -531,7 +531,7 @@ function test_sanitize() {
 		);
 		foreach ( $valid_urls as $valid_url ) {
 			$url_setting = $setting->sanitize( array( 'url' => $valid_url ) );
-			$this->assertInternalType( 'array', $url_setting );
+			$this->assertIsArray( $url_setting );
 			$this->assertEquals( $valid_url, $url_setting['url'] );
 		}
 
diff --git a/tests/phpunit/tests/customize/nav-menu-setting.php b/tests/phpunit/tests/customize/nav-menu-setting.php
index 53b0d88ac8db..bc29b49bcbcf 100644
--- a/tests/phpunit/tests/customize/nav-menu-setting.php
+++ b/tests/phpunit/tests/customize/nav-menu-setting.php
@@ -70,7 +70,7 @@ function test_construct() {
 		$this->assertNull( $setting->previous_term_id );
 		$this->assertNull( $setting->update_status );
 		$this->assertNull( $setting->update_error );
-		$this->assertInternalType( 'array', $setting->default );
+		$this->assertIsArray( $setting->default );
 		foreach ( array( 'name', 'description', 'parent' ) as $key ) {
 			$this->assertArrayHasKey( $key, $setting->default );
 		}
@@ -149,7 +149,7 @@ function test_value() {
 		$setting    = new WP_Customize_Nav_Menu_Setting( $this->wp_customize, $setting_id );
 
 		$value = $setting->value();
-		$this->assertInternalType( 'array', $value );
+		$this->assertIsArray( $value );
 		foreach ( array( 'name', 'description', 'parent' ) as $key ) {
 			$this->assertArrayHasKey( $key, $value );
 		}
@@ -304,7 +304,7 @@ function test_preview_deleted() {
 
 		$this->wp_customize->set_post_value( $setting_id, false );
 
-		$this->assertInternalType( 'array', $setting->value() );
+		$this->assertIsArray( $setting->value() );
 		$this->assertInternalType( 'object', wp_get_nav_menu_object( $menu_id ) );
 		$setting->preview();
 		$this->assertFalse( $setting->value() );
diff --git a/tests/phpunit/tests/customize/nav-menus.php b/tests/phpunit/tests/customize/nav-menus.php
index 3698c818395d..4bae45353062 100644
--- a/tests/phpunit/tests/customize/nav-menus.php
+++ b/tests/phpunit/tests/customize/nav-menus.php
@@ -381,7 +381,7 @@ function test_search_available_items_query() {
 			)
 		);
 		$this->assertEquals( $count + 1, $this->filter_count_customize_nav_menu_searched_items );
-		$this->assertInternalType( 'array', $results );
+		$this->assertIsArray( $results );
 		$this->assertCount( 3, $results );
 		remove_filter( 'customize_nav_menu_searched_items', array( $this, 'filter_search' ), 10 );
 
@@ -465,8 +465,8 @@ public function test_search_available_items_query_should_return_unassigned_term_
 	 * @return array Items.
 	 */
 	function filter_search( $items, $args ) {
-		$this->assertInternalType( 'array', $items );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $items );
+		$this->assertIsArray( $args );
 		$this->assertArrayHasKey( 's', $args );
 		$this->assertArrayHasKey( 'pagenum', $args );
 		$this->filter_count_customize_nav_menu_searched_items += 1;
@@ -804,13 +804,13 @@ function test_customize_dynamic_partial_args() {
 		do_action( 'customize_register', $this->wp_customize );
 
 		$args = apply_filters( 'customize_dynamic_partial_args', false, 'nav_menu_instance[68b329da9893e34099c7d8ad5cb9c940]' );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->assertEquals( 'nav_menu_instance', $args['type'] );
 		$this->assertEquals( array( $this->wp_customize->nav_menus, 'render_nav_menu_partial' ), $args['render_callback'] );
 		$this->assertTrue( $args['container_inclusive'] );
 
 		$args = apply_filters( 'customize_dynamic_partial_args', array( 'fallback_refresh' => false ), 'nav_menu_instance[4099c7d8ad5cb9c94068b329da9893e3]' );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->assertEquals( 'nav_menu_instance', $args['type'] );
 		$this->assertEquals( array( $this->wp_customize->nav_menus, 'render_nav_menu_partial' ), $args['render_callback'] );
 		$this->assertTrue( $args['container_inclusive'] );
diff --git a/tests/phpunit/tests/customize/partial.php b/tests/phpunit/tests/customize/partial.php
index c8183d7be6a0..f6f14f501379 100644
--- a/tests/phpunit/tests/customize/partial.php
+++ b/tests/phpunit/tests/customize/partial.php
@@ -166,7 +166,7 @@ function test_id_data() {
 	function filter_customize_partial_render( $rendered, $partial, $container_context ) {
 		$this->assertTrue( false === $rendered || is_string( $rendered ) );
 		$this->assertInstanceOf( 'WP_Customize_Partial', $partial );
-		$this->assertInternalType( 'array', $container_context );
+		$this->assertIsArray( $container_context );
 		$this->count_filter_customize_partial_render += 1;
 		return $rendered;
 	}
@@ -183,7 +183,7 @@ function filter_customize_partial_render_with_id( $rendered, $partial, $containe
 		$this->assertEquals( sprintf( 'customize_partial_render_%s', $partial->id ), current_filter() );
 		$this->assertTrue( false === $rendered || is_string( $rendered ) );
 		$this->assertInstanceOf( 'WP_Customize_Partial', $partial );
-		$this->assertInternalType( 'array', $container_context );
+		$this->assertIsArray( $container_context );
 		$this->count_filter_customize_partial_render_with_id += 1;
 		return $rendered;
 	}
diff --git a/tests/phpunit/tests/customize/selective-refresh-ajax.php b/tests/phpunit/tests/customize/selective-refresh-ajax.php
index 2bd49e3d610e..d70505aad2b5 100644
--- a/tests/phpunit/tests/customize/selective-refresh-ajax.php
+++ b/tests/phpunit/tests/customize/selective-refresh-ajax.php
@@ -160,7 +160,7 @@ function test_handle_render_partials_request_for_unrecognized_partial() {
 		}
 		$output = json_decode( ob_get_clean(), true );
 		$this->assertTrue( $output['success'] );
-		$this->assertInternalType( 'array', $output['data'] );
+		$this->assertIsArray( $output['data'] );
 		$this->assertArrayHasKey( 'contents', $output['data'] );
 		$this->assertArrayHasKey( 'errors', $output['data'] );
 		$this->assertArrayHasKey( 'foo', $output['data']['contents'] );
@@ -280,7 +280,7 @@ function test_handle_rendering_partial_with_missing_settings() {
 	 * @return string
 	 */
 	function render_callback_blogname( $partial, $context ) {
-		$this->assertInternalType( 'array', $context );
+		$this->assertIsArray( $context );
 		$this->assertInstanceOf( 'WP_Customize_Partial', $partial );
 		return get_bloginfo( 'name', 'display' );
 	}
@@ -293,7 +293,7 @@ function render_callback_blogname( $partial, $context ) {
 	 * @return string
 	 */
 	function render_callback_blogdescription( $partial, $context ) {
-		$this->assertInternalType( 'array', $context );
+		$this->assertIsArray( $context );
 		$this->assertInstanceOf( 'WP_Customize_Partial', $partial );
 		$x = get_bloginfo( 'description', 'display' );
 		return $x;
@@ -374,7 +374,7 @@ function filter_customize_dynamic_partial_args( $partial_args, $partial_id ) {
 	 * @return array Response.
 	 */
 	function filter_customize_render_partials_response( $response, $component, $partial_placements ) {
-		$this->assertInternalType( 'array', $response );
+		$this->assertIsArray( $response );
 		$this->assertInstanceOf( 'WP_Customize_Selective_Refresh', $component );
 		if ( isset( $this->expected_partial_ids ) ) {
 			$this->assertEqualSets( $this->expected_partial_ids, array_keys( $partial_placements ) );
diff --git a/tests/phpunit/tests/customize/selective-refresh.php b/tests/phpunit/tests/customize/selective-refresh.php
index ed4d9ef683c6..9f92dce9cde2 100644
--- a/tests/phpunit/tests/customize/selective-refresh.php
+++ b/tests/phpunit/tests/customize/selective-refresh.php
@@ -71,7 +71,7 @@ function test_register_scripts() {
 	 * @see WP_Customize_Selective_Refresh::partials()
 	 */
 	function test_partials() {
-		$this->assertInternalType( 'array', $this->selective_refresh->partials() );
+		$this->assertIsArray( $this->selective_refresh->partials() );
 	}
 
 	/**
@@ -163,9 +163,9 @@ function test_export_preview_data() {
 		$html = ob_get_clean();
 		$this->assertTrue( (bool) preg_match( '/_customizePartialRefreshExports = ({.+})/s', $html, $matches ) );
 		$exported_data = json_decode( $matches[1], true );
-		$this->assertInternalType( 'array', $exported_data );
+		$this->assertIsArray( $exported_data );
 		$this->assertArrayHasKey( 'partials', $exported_data );
-		$this->assertInternalType( 'array', $exported_data['partials'] );
+		$this->assertIsArray( $exported_data['partials'] );
 		$this->assertArrayHasKey( 'blogname', $exported_data['partials'] );
 		$this->assertArrayNotHasKey( 'top_secret_message', $exported_data['partials'] );
 		$this->assertEquals( '#site-title', $exported_data['partials']['blogname']['selector'] );
@@ -230,7 +230,7 @@ function filter_customize_dynamic_partial_args( $partial_args, $partial_id ) {
 	 * @return string
 	 */
 	function filter_customize_dynamic_partial_class( $partial_class, $partial_id, $partial_args ) {
-		$this->assertInternalType( 'array', $partial_args );
+		$this->assertIsArray( $partial_args );
 		$this->assertInternalType( 'string', $partial_id );
 		$this->assertInternalType( 'string', $partial_class );
 
diff --git a/tests/phpunit/tests/customize/widgets.php b/tests/phpunit/tests/customize/widgets.php
index 0b95c94b2b14..b5abb2dab73a 100644
--- a/tests/phpunit/tests/customize/widgets.php
+++ b/tests/phpunit/tests/customize/widgets.php
@@ -120,7 +120,7 @@ function test_get_selective_refreshable_widgets_when_theme_supports() {
 		$this->do_customize_boot_actions();
 
 		$selective_refreshable_widgets = $this->manager->widgets->get_selective_refreshable_widgets();
-		$this->assertInternalType( 'array', $selective_refreshable_widgets );
+		$this->assertIsArray( $selective_refreshable_widgets );
 		$this->assertEquals( count( $wp_widget_factory->widgets ), count( $selective_refreshable_widgets ) );
 		$this->assertArrayHasKey( 'text', $selective_refreshable_widgets );
 		$this->assertTrue( $selective_refreshable_widgets['text'] );
@@ -493,7 +493,7 @@ function test_call_widget_update() {
 		$this->assertArrayNotHasKey( $setting_id, $this->manager->unsanitized_post_values() );
 		$result = $this->manager->widgets->call_widget_update( $widget_id );
 
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertArrayHasKey( 'instance', $result );
 		$this->assertArrayHasKey( 'form', $result );
 		$this->assertEquals( $instance, $result['instance'] );
@@ -502,7 +502,7 @@ function test_call_widget_update() {
 		$post_values = $this->manager->unsanitized_post_values();
 		$this->assertArrayHasKey( $setting_id, $post_values );
 		$post_value = $post_values[ $setting_id ];
-		$this->assertInternalType( 'array', $post_value );
+		$this->assertIsArray( $post_value );
 		$this->assertArrayHasKey( 'title', $post_value );
 		$this->assertArrayHasKey( 'encoded_serialized_instance', $post_value );
 		$this->assertArrayHasKey( 'instance_hash_key', $post_value );
@@ -519,13 +519,13 @@ function test_customize_dynamic_partial_args() {
 		do_action( 'customize_register', $this->manager );
 
 		$args = apply_filters( 'customize_dynamic_partial_args', false, 'widget[search-2]' );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->assertEquals( 'widget', $args['type'] );
 		$this->assertEquals( array( $this->manager->widgets, 'render_widget_partial' ), $args['render_callback'] );
 		$this->assertTrue( $args['container_inclusive'] );
 
 		$args = apply_filters( 'customize_dynamic_partial_args', array( 'fallback_refresh' => false ), 'widget[search-2]' );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->assertEquals( 'widget', $args['type'] );
 		$this->assertEquals( array( $this->manager->widgets, 'render_widget_partial' ), $args['render_callback'] );
 		$this->assertTrue( $args['container_inclusive'] );
diff --git a/tests/phpunit/tests/db.php b/tests/phpunit/tests/db.php
index 26346f2df0ba..37232065e105 100644
--- a/tests/phpunit/tests/db.php
+++ b/tests/phpunit/tests/db.php
@@ -1690,7 +1690,7 @@ public function test_parse_db_host( $host_string, $expect_bail, $host, $port, $s
 		if ( $expect_bail ) {
 			$this->assertFalse( $data );
 		} else {
-			$this->assertInternalType( 'array', $data );
+			$this->assertIsArray( $data );
 
 			list( $parsed_host, $parsed_port, $parsed_socket, $parsed_is_ipv6 ) = $data;
 
diff --git a/tests/phpunit/tests/functions.php b/tests/phpunit/tests/functions.php
index ad7ba280d974..734f1daa04df 100644
--- a/tests/phpunit/tests/functions.php
+++ b/tests/phpunit/tests/functions.php
@@ -557,17 +557,17 @@ function test_add_query_arg_numeric_keys() {
 	function test_get_allowed_mime_types() {
 		$mimes = get_allowed_mime_types();
 
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertNotEmpty( $mimes );
 
 		add_filter( 'upload_mimes', '__return_empty_array' );
 		$mimes = get_allowed_mime_types();
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertEmpty( $mimes );
 
 		remove_filter( 'upload_mimes', '__return_empty_array' );
 		$mimes = get_allowed_mime_types();
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertNotEmpty( $mimes );
 	}
 
@@ -577,28 +577,28 @@ function test_get_allowed_mime_types() {
 	function test_wp_get_mime_types() {
 		$mimes = wp_get_mime_types();
 
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertNotEmpty( $mimes );
 
 		add_filter( 'mime_types', '__return_empty_array' );
 		$mimes = wp_get_mime_types();
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertEmpty( $mimes );
 
 		remove_filter( 'mime_types', '__return_empty_array' );
 		$mimes = wp_get_mime_types();
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertNotEmpty( $mimes );
 
 		// 'upload_mimes' should not affect wp_get_mime_types().
 		add_filter( 'upload_mimes', '__return_empty_array' );
 		$mimes = wp_get_mime_types();
-		$this->assertInternalType( 'array', $mimes );
+		$this->assertIsArray( $mimes );
 		$this->assertNotEmpty( $mimes );
 
 		remove_filter( 'upload_mimes', '__return_empty_array' );
 		$mimes2 = wp_get_mime_types();
-		$this->assertInternalType( 'array', $mimes2 );
+		$this->assertIsArray( $mimes2 );
 		$this->assertNotEmpty( $mimes2 );
 		$this->assertEquals( $mimes2, $mimes );
 	}
@@ -886,7 +886,7 @@ function test_wp_extract_urls() {
 
 		$urls = wp_extract_urls( $blob );
 		$this->assertNotEmpty( $urls );
-		$this->assertInternalType( 'array', $urls );
+		$this->assertIsArray( $urls );
 		$this->assertCount( count( $original_urls ), $urls );
 		$this->assertEquals( $original_urls, $urls );
 
@@ -907,7 +907,7 @@ function test_wp_extract_urls() {
 
 		$urls = wp_extract_urls( $blob );
 		$this->assertNotEmpty( $urls );
-		$this->assertInternalType( 'array', $urls );
+		$this->assertIsArray( $urls );
 		$this->assertCount( 8, $urls );
 		$this->assertEquals( array_slice( $original_urls, 0, 8 ), $urls );
 
@@ -921,7 +921,7 @@ function test_wp_extract_urls() {
 
 		$urls = wp_extract_urls( $blob );
 		$this->assertNotEmpty( $urls );
-		$this->assertInternalType( 'array', $urls );
+		$this->assertIsArray( $urls );
 		$this->assertCount( 8, $urls );
 		$this->assertEquals( array_slice( $original_urls, 0, 8 ), $urls );
 	}
@@ -1048,7 +1048,7 @@ function datetime_provider() {
 	public function test_wp_get_ext_types() {
 		$extensions = wp_get_ext_types();
 
-		$this->assertInternalType( 'array', $extensions );
+		$this->assertIsArray( $extensions );
 		$this->assertNotEmpty( $extensions );
 
 		add_filter( 'ext2type', '__return_empty_array' );
@@ -1057,7 +1057,7 @@ public function test_wp_get_ext_types() {
 
 		remove_filter( 'ext2type', '__return_empty_array' );
 		$extensions = wp_get_ext_types();
-		$this->assertInternalType( 'array', $extensions );
+		$this->assertIsArray( $extensions );
 		$this->assertNotEmpty( $extensions );
 	}
 
diff --git a/tests/phpunit/tests/functions/listFiles.php b/tests/phpunit/tests/functions/listFiles.php
index d461e0c19581..15e4befe7c97 100644
--- a/tests/phpunit/tests/functions/listFiles.php
+++ b/tests/phpunit/tests/functions/listFiles.php
@@ -8,7 +8,7 @@
 class Tests_Functions_ListFiles extends WP_UnitTestCase {
 	public function test_list_files_returns_a_list_of_files() {
 		$admin_files = list_files( ABSPATH . 'wp-admin/' );
-		$this->assertInternalType( 'array', $admin_files );
+		$this->assertIsArray( $admin_files );
 		$this->assertNotEmpty( $admin_files );
 		$this->assertContains( ABSPATH . 'wp-admin/index.php', $admin_files );
 	}
diff --git a/tests/phpunit/tests/functions/wpGetMimeTypes.php b/tests/phpunit/tests/functions/wpGetMimeTypes.php
index 8188ecd51831..23d7733ea7a6 100644
--- a/tests/phpunit/tests/functions/wpGetMimeTypes.php
+++ b/tests/phpunit/tests/functions/wpGetMimeTypes.php
@@ -13,7 +13,7 @@ class Tests_Functions_wpGetMimeTypes extends WP_UnitTestCase {
 	public function test_all_mime_match() {
 		$mime_types_start = wp_get_mime_types();
 
-		$this->assertInternalType( 'array', $mime_types_start );
+		$this->assertIsArray( $mime_types_start );
 		$this->assertNotEmpty( $mime_types_start );
 
 		add_filter( 'mime_types', '__return_empty_array' );
@@ -22,7 +22,7 @@ public function test_all_mime_match() {
 
 		remove_filter( 'mime_types', '__return_empty_array' );
 		$mime_types = wp_get_mime_types();
-		$this->assertInternalType( 'array', $mime_types );
+		$this->assertIsArray( $mime_types );
 		$this->assertNotEmpty( $mime_types );
 		// Did it revert to the original after filter remove?
 		$this->assertSame( $mime_types_start, $mime_types );
diff --git a/tests/phpunit/tests/http/base.php b/tests/phpunit/tests/http/base.php
index 5100fd6117c3..15bc1731e451 100644
--- a/tests/phpunit/tests/http/base.php
+++ b/tests/phpunit/tests/http/base.php
@@ -403,7 +403,7 @@ function test_multiple_location_headers() {
 		$res = wp_remote_head( $url, array( 'timeout' => 30 ) );
 
 		$this->skipTestOnTimeout( $res );
-		$this->assertInternalType( 'array', wp_remote_retrieve_header( $res, 'location' ) );
+		$this->assertIsArray( wp_remote_retrieve_header( $res, 'location' ) );
 		$this->assertCount( 2, wp_remote_retrieve_header( $res, 'location' ) );
 
 		$res = wp_remote_get( $url, array( 'timeout' => 30 ) );
diff --git a/tests/phpunit/tests/http/functions.php b/tests/phpunit/tests/http/functions.php
index 66cb6b52fe4d..3029aba74697 100644
--- a/tests/phpunit/tests/http/functions.php
+++ b/tests/phpunit/tests/http/functions.php
@@ -23,7 +23,7 @@ function test_head_request() {
 
 		$headers = wp_remote_retrieve_headers( $response );
 
-		$this->assertInternalType( 'array', $response );
+		$this->assertIsArray( $response );
 
 		$this->assertEquals( 'image/jpeg', $headers['content-type'] );
 		$this->assertEquals( '40148', $headers['content-length'] );
@@ -56,7 +56,7 @@ function test_get_request() {
 
 		$headers = wp_remote_retrieve_headers( $response );
 
-		$this->assertInternalType( 'array', $response );
+		$this->assertIsArray( $response );
 
 		// Should return the same headers as a HEAD request.
 		$this->assertEquals( 'image/jpeg', $headers['content-type'] );
diff --git a/tests/phpunit/tests/image/intermediateSize.php b/tests/phpunit/tests/image/intermediateSize.php
index 394353c6508d..1c354605cb57 100644
--- a/tests/phpunit/tests/image/intermediateSize.php
+++ b/tests/phpunit/tests/image/intermediateSize.php
@@ -35,7 +35,7 @@ function test_make_intermediate_size_width() {
 
 		$image = image_make_intermediate_size( DIR_TESTDATA . '/images/a2-small.jpg', 100, 0, false );
 
-		$this->assertInternalType( 'array', $image );
+		$this->assertIsArray( $image );
 	}
 
 	function test_make_intermediate_size_height() {
@@ -45,7 +45,7 @@ function test_make_intermediate_size_height() {
 
 		$image = image_make_intermediate_size( DIR_TESTDATA . '/images/a2-small.jpg', 0, 75, false );
 
-		$this->assertInternalType( 'array', $image );
+		$this->assertIsArray( $image );
 	}
 
 	function test_make_intermediate_size_successful() {
@@ -55,7 +55,7 @@ function test_make_intermediate_size_successful() {
 
 		$image = image_make_intermediate_size( DIR_TESTDATA . '/images/a2-small.jpg', 100, 75, true );
 
-		$this->assertInternalType( 'array', $image );
+		$this->assertIsArray( $image );
 		$this->assertEquals( 100, $image['width'] );
 		$this->assertEquals( 75, $image['height'] );
 		$this->assertEquals( 'image/jpeg', $image['mime-type'] );
diff --git a/tests/phpunit/tests/l10n.php b/tests/phpunit/tests/l10n.php
index 381b865557ba..94406697a4d2 100644
--- a/tests/phpunit/tests/l10n.php
+++ b/tests/phpunit/tests/l10n.php
@@ -56,7 +56,7 @@ function test_before_last_bar() {
 	 */
 	function test_get_available_languages() {
 		$array = get_available_languages();
-		$this->assertInternalType( 'array', $array );
+		$this->assertIsArray( $array );
 
 		$array = get_available_languages( '.' );
 		$this->assertEmpty( $array );
@@ -70,7 +70,7 @@ function test_get_available_languages() {
 	 */
 	function test_wp_get_installed_translations_for_core() {
 		$installed_translations = wp_get_installed_translations( 'core' );
-		$this->assertInternalType( 'array', $installed_translations );
+		$this->assertIsArray( $installed_translations );
 		$textdomains_expected = array( 'admin', 'admin-network', 'continents-cities', 'default' );
 		$this->assertEqualSets( $textdomains_expected, array_keys( $installed_translations ) );
 
diff --git a/tests/phpunit/tests/media.php b/tests/phpunit/tests/media.php
index 34a1414da3b5..6b6b1d82f955 100644
--- a/tests/phpunit/tests/media.php
+++ b/tests/phpunit/tests/media.php
@@ -349,7 +349,7 @@ function test_wp_prepare_attachment_for_js() {
 		$post = get_post( $id );
 
 		$prepped = wp_prepare_attachment_for_js( $post );
-		$this->assertInternalType( 'array', $prepped );
+		$this->assertIsArray( $prepped );
 		$this->assertEquals( 0, $prepped['uploadedTo'] );
 		$this->assertEquals( '', $prepped['mime'] );
 		$this->assertEquals( '', $prepped['type'] );
diff --git a/tests/phpunit/tests/oembed/controller.php b/tests/phpunit/tests/oembed/controller.php
index 023f82fd1192..a0603f961299 100644
--- a/tests/phpunit/tests/oembed/controller.php
+++ b/tests/phpunit/tests/oembed/controller.php
@@ -169,7 +169,7 @@ public function filter_oembed_result( $data, $url, $args ) {
 			$this->fail( 'Unexpected type for $data.' );
 		}
 		$this->assertInternalType( 'string', $url );
-		$this->assertInternalType( 'array', $args );
+		$this->assertIsArray( $args );
 		$this->oembed_result_filter_count++;
 		return $data;
 	}
@@ -298,7 +298,7 @@ function test_request_invalid_format() {
 		$response = rest_get_server()->dispatch( $request );
 		$data     = $response->get_data();
 
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertNotEmpty( $data );
 	}
 
@@ -322,7 +322,7 @@ function test_request_json() {
 		$response = rest_get_server()->dispatch( $request );
 		$data     = $response->get_data();
 
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertNotEmpty( $data );
 
 		$this->assertArrayHasKey( 'version', $data );
@@ -365,7 +365,7 @@ function test_request_static_front_page() {
 		$response = rest_get_server()->dispatch( $request );
 		$data     = $response->get_data();
 
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertNotEmpty( $data );
 
 		$this->assertArrayHasKey( 'version', $data );
@@ -410,7 +410,7 @@ function test_request_xml() {
 		$response = rest_get_server()->dispatch( $request );
 		$data     = $response->get_data();
 
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertNotEmpty( $data );
 
 		$this->assertArrayHasKey( 'version', $data );
@@ -453,7 +453,7 @@ function test_request_ms_child_in_root_blog() {
 		$response = rest_get_server()->dispatch( $request );
 		$data     = $response->get_data();
 
-		$this->assertInternalType( 'array', $data );
+		$this->assertIsArray( $data );
 		$this->assertNotEmpty( $data );
 
 		restore_current_blog();
@@ -631,7 +631,7 @@ public function test_proxy_with_classic_embed_provider() {
 		$this->assertNotEmpty( $data );
 		$this->assertInternalType( 'object', $data );
 		$this->assertInternalType( 'string', $data->html );
-		$this->assertInternalType( 'array', $data->scripts );
+		$this->assertIsArray( $data->scripts );
 	}
 
 	public function test_proxy_with_invalid_oembed_provider_no_discovery() {
diff --git a/tests/phpunit/tests/post.php b/tests/phpunit/tests/post.php
index aedbe404bc75..cea1d2fe8af9 100644
--- a/tests/phpunit/tests/post.php
+++ b/tests/phpunit/tests/post.php
@@ -97,12 +97,12 @@ function test_vb_insert_get_delete() {
 
 			update_object_term_cache( $id, $post_type );
 			$tcache = wp_cache_get( $id, 'post_tag_relationships' );
-			$this->assertInternalType( 'array', $tcache );
+			$this->assertIsArray( $tcache );
 			$this->assertEquals( 2, count( $tcache ) );
 
 			$tcache = wp_cache_get( $id, 'ctax_relationships' );
 			if ( 'cpt' === $post_type ) {
-				$this->assertInternalType( 'array', $tcache );
+				$this->assertIsArray( $tcache );
 				$this->assertEquals( 2, count( $tcache ) );
 			} else {
 				$this->assertFalse( $tcache );
diff --git a/tests/phpunit/tests/post/formats.php b/tests/phpunit/tests/post/formats.php
index e32fc847b91b..f86687b3e094 100644
--- a/tests/phpunit/tests/post/formats.php
+++ b/tests/phpunit/tests/post/formats.php
@@ -16,7 +16,7 @@ function test_set_get_post_format_for_post() {
 
 		$result = set_post_format( $post_id, 'aside' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 1, count( $result ) );
 
 		$format = get_post_format( $post_id );
@@ -24,12 +24,12 @@ function test_set_get_post_format_for_post() {
 
 		$result = set_post_format( $post_id, 'standard' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 
 		$result = set_post_format( $post_id, '' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 	}
 
@@ -44,7 +44,7 @@ function test_set_get_post_format_for_page() {
 
 		$result = set_post_format( $post_id, 'aside' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 1, count( $result ) );
 		// The format can be set but not retrieved until it is registered.
 		$format = get_post_format( $post_id );
@@ -57,12 +57,12 @@ function test_set_get_post_format_for_page() {
 
 		$result = set_post_format( $post_id, 'standard' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 
 		$result = set_post_format( $post_id, '' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 
 		remove_post_type_support( 'page', 'post-formats' );
@@ -76,13 +76,13 @@ function test_has_format() {
 
 		$result = set_post_format( $post_id, 'aside' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 1, count( $result ) );
 		$this->assertTrue( has_post_format( 'aside', $post_id ) );
 
 		$result = set_post_format( $post_id, 'standard' );
 		$this->assertNotWPError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 		// Standard is a special case. It shows as false when set.
 		$this->assertFalse( has_post_format( 'standard', $post_id ) );
diff --git a/tests/phpunit/tests/post/getPageByPath.php b/tests/phpunit/tests/post/getPageByPath.php
index 9b288b64f64b..f5fe67b4457a 100644
--- a/tests/phpunit/tests/post/getPageByPath.php
+++ b/tests/phpunit/tests/post/getPageByPath.php
@@ -310,11 +310,11 @@ public function test_output_param_should_be_obeyed_for_cached_value() {
 		$this->assertSame( $page, $object->ID );
 
 		$array_n = get_page_by_path( 'foo', ARRAY_N );
-		$this->assertInternalType( 'array', $array_n );
+		$this->assertIsArray( $array_n );
 		$this->assertSame( $page, $array_n[0] );
 
 		$array_a = get_page_by_path( 'foo', ARRAY_A );
-		$this->assertInternalType( 'array', $array_a );
+		$this->assertIsArray( $array_a );
 		$this->assertSame( $page, $array_a['ID'] );
 	}
 }
diff --git a/tests/phpunit/tests/post/objects.php b/tests/phpunit/tests/post/objects.php
index 5451f73b542f..8b03053302c8 100644
--- a/tests/phpunit/tests/post/objects.php
+++ b/tests/phpunit/tests/post/objects.php
@@ -30,17 +30,17 @@ function test_get_post() {
 
 		// Excercise the output argument.
 		$post = get_post( $id, ARRAY_A );
-		$this->assertInternalType( 'array', $post );
+		$this->assertIsArray( $post );
 		$this->assertEquals( 'post', $post['post_type'] );
 
 		$post = get_post( $id, ARRAY_N );
-		$this->assertInternalType( 'array', $post );
+		$this->assertIsArray( $post );
 		$this->assertFalse( isset( $post['post_type'] ) );
 		$this->assertTrue( in_array( 'post', $post, true ) );
 
 		$post = get_post( $id );
 		$post = get_post( $post, ARRAY_A );
-		$this->assertInternalType( 'array', $post );
+		$this->assertIsArray( $post );
 		$this->assertEquals( 'post', $post['post_type'] );
 		$this->assertEquals( $id, $post['ID'] );
 
@@ -51,7 +51,7 @@ function test_get_post() {
 
 		// Make sure stdClass in $GLOBALS['post'] is handled.
 		$post_std = $post->to_array();
-		$this->assertInternalType( 'array', $post_std );
+		$this->assertIsArray( $post_std );
 		$post_std        = (object) $post_std;
 		$GLOBALS['post'] = $post_std;
 		$post            = get_post( null );
@@ -103,7 +103,7 @@ function test_get_post_ancestors() {
 	 */
 	function test_get_post_ancestors_with_falsey_values() {
 		foreach ( array( null, 0, false, '0', '' ) as $post_id ) {
-			$this->assertInternalType( 'array', get_post_ancestors( $post_id ) );
+			$this->assertIsArray( get_post_ancestors( $post_id ) );
 			$this->assertEquals( array(), get_post_ancestors( $post_id ) );
 		}
 	}
@@ -112,7 +112,7 @@ function test_get_post_category_property() {
 		$post_id = self::factory()->post->create();
 		$post    = get_post( $post_id );
 
-		$this->assertInternalType( 'array', $post->post_category );
+		$this->assertIsArray( $post->post_category );
 		$this->assertEquals( 1, count( $post->post_category ) );
 		$this->assertEquals( get_option( 'default_category' ), $post->post_category[0] );
 		$term1 = wp_insert_term( 'Foo', 'category' );
@@ -131,15 +131,15 @@ function test_get_tags_input_property() {
 		$post_id = self::factory()->post->create();
 		$post    = get_post( $post_id );
 
-		$this->assertInternalType( 'array', $post->tags_input );
+		$this->assertIsArray( $post->tags_input );
 		$this->assertEmpty( $post->tags_input );
 		wp_set_post_tags( $post_id, 'Foo, Bar, Baz' );
-		$this->assertInternalType( 'array', $post->tags_input );
+		$this->assertIsArray( $post->tags_input );
 		$this->assertEquals( 3, count( $post->tags_input ) );
 		$this->assertEquals( array( 'Bar', 'Baz', 'Foo' ), $post->tags_input );
 
 		$post = get_post( $post_id, ARRAY_A );
-		$this->assertInternalType( 'array', $post['tags_input'] );
+		$this->assertIsArray( $post['tags_input'] );
 		$this->assertEquals( 3, count( $post['tags_input'] ) );
 		$this->assertEquals( array( 'Bar', 'Baz', 'Foo' ), $post['tags_input'] );
 	}
@@ -199,7 +199,7 @@ function test_get_post_array() {
 		$post = get_post( $id, ARRAY_A );
 
 		$this->assertEquals( $id, $post['ID'] );
-		$this->assertInternalType( 'array', $post['ancestors'] );
+		$this->assertIsArray( $post['ancestors'] );
 		$this->assertEquals( 'raw', $post['filter'] );
 	}
 
diff --git a/tests/phpunit/tests/rest-api/rest-comments-controller.php b/tests/phpunit/tests/rest-api/rest-comments-controller.php
index 3ace6d6da61f..36f8516f4380 100644
--- a/tests/phpunit/tests/rest-api/rest-comments-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-comments-controller.php
@@ -2833,7 +2833,7 @@ public function verify_comment_roundtrip( $input = array(), $expected_output = a
 		$actual_output = $response->get_data();
 
 		// Compare expected API output to actual API output.
-		$this->assertInternalType( 'array', $actual_output['content'] );
+		$this->assertIsArray( $actual_output['content'] );
 		$this->assertArrayHasKey( 'raw', $actual_output['content'] );
 		$this->assertEquals( $expected_output['content']['raw'], $actual_output['content']['raw'] );
 		$this->assertEquals( $expected_output['content']['rendered'], trim( $actual_output['content']['rendered'] ) );
diff --git a/tests/phpunit/tests/rest-api/rest-post-meta-fields.php b/tests/phpunit/tests/rest-api/rest-post-meta-fields.php
index 6cdb9743c7ed..cd73a83e2251 100644
--- a/tests/phpunit/tests/rest-api/rest-post-meta-fields.php
+++ b/tests/phpunit/tests/rest-api/rest-post-meta-fields.php
@@ -290,7 +290,7 @@ public function test_get_multi_value() {
 		$data = $response->get_data();
 		$meta = (array) $data['meta'];
 		$this->assertArrayHasKey( 'test_multi', $meta );
-		$this->assertInternalType( 'array', $meta['test_multi'] );
+		$this->assertIsArray( $meta['test_multi'] );
 		$this->assertContains( 'value1', $meta['test_multi'] );
 
 		// Check after an update.
@@ -1211,7 +1211,7 @@ public function test_get_subtype_meta_value( $post_type, $meta_key, $single, $in
 		$data = $response->get_data();
 
 		$this->assertArrayHasKey( 'meta', $data );
-		$this->assertInternalType( 'array', $data['meta'] );
+		$this->assertIsArray( $data['meta'] );
 
 		if ( $in_post_type ) {
 			$expected_value = $meta_value;
@@ -1277,7 +1277,7 @@ public function test_set_subtype_meta_value( $post_type, $meta_key, $single, $in
 
 		$data = $response->get_data();
 		$this->assertArrayHasKey( 'meta', $data );
-		$this->assertInternalType( 'array', $data['meta'] );
+		$this->assertIsArray( $data['meta'] );
 
 		if ( $in_post_type ) {
 			$expected_value = $meta_value;
diff --git a/tests/phpunit/tests/rest-api/rest-server.php b/tests/phpunit/tests/rest-api/rest-server.php
index b9fd3db750ed..a00d3ff509f1 100644
--- a/tests/phpunit/tests/rest-api/rest-server.php
+++ b/tests/phpunit/tests/rest-api/rest-server.php
@@ -532,7 +532,7 @@ public function test_link_embedding() {
 		$this->assertCount( 2, $alternate );
 		$this->assertEmpty( $alternate[0] );
 
-		$this->assertInternalType( 'array', $alternate[1] );
+		$this->assertIsArray( $alternate[1] );
 		$this->assertArrayNotHasKey( 'code', $alternate[1] );
 		$this->assertTrue( $alternate[1]['hello'] );
 
diff --git a/tests/phpunit/tests/rest-api/rest-term-meta-fields.php b/tests/phpunit/tests/rest-api/rest-term-meta-fields.php
index bf9a26d854b4..9e882e9bd1d3 100644
--- a/tests/phpunit/tests/rest-api/rest-term-meta-fields.php
+++ b/tests/phpunit/tests/rest-api/rest-term-meta-fields.php
@@ -237,7 +237,7 @@ public function test_get_multi_value() {
 		$data = $response->get_data();
 		$meta = (array) $data['meta'];
 		$this->assertArrayHasKey( 'test_multi', $meta );
-		$this->assertInternalType( 'array', $meta['test_multi'] );
+		$this->assertIsArray( $meta['test_multi'] );
 		$this->assertContains( 'value1', $meta['test_multi'] );
 
 		// Check after an update.
@@ -1157,7 +1157,7 @@ public function test_get_subtype_meta_value( $taxonomy, $meta_key, $single, $in_
 		$data = $response->get_data();
 
 		$this->assertArrayHasKey( 'meta', $data );
-		$this->assertInternalType( 'array', $data['meta'] );
+		$this->assertIsArray( $data['meta'] );
 
 		if ( $in_taxonomy ) {
 			$expected_value = $meta_value;
@@ -1221,7 +1221,7 @@ public function test_set_subtype_meta_value( $taxonomy, $meta_key, $single, $in_
 
 		$data = $response->get_data();
 		$this->assertArrayHasKey( 'meta', $data );
-		$this->assertInternalType( 'array', $data['meta'] );
+		$this->assertIsArray( $data['meta'] );
 
 		if ( $in_taxonomy ) {
 			$expected_value = $meta_value;
diff --git a/tests/phpunit/tests/rest-api/rest-users-controller.php b/tests/phpunit/tests/rest-api/rest-users-controller.php
index 98edd36ee396..d0f136f00407 100644
--- a/tests/phpunit/tests/rest-api/rest-users-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-users-controller.php
@@ -1211,13 +1211,13 @@ public function test_create_item_invalid_username() {
 		$data = $response->get_data();
 
 		if ( is_multisite() ) {
-			$this->assertInternalType( 'array', $data['additional_errors'] );
+			$this->assertIsArray( $data['additional_errors'] );
 			$this->assertCount( 1, $data['additional_errors'] );
 			$error = $data['additional_errors'][0];
 			$this->assertEquals( 'user_name', $error['code'] );
 			$this->assertEquals( 'Usernames can only contain lowercase letters (a-z) and numbers.', $error['message'] );
 		} else {
-			$this->assertInternalType( 'array', $data['data']['params'] );
+			$this->assertIsArray( $data['data']['params'] );
 			$errors = $data['data']['params'];
 			$this->assertInternalType( 'string', $errors['username'] );
 			$this->assertEquals( 'This username is invalid because it uses illegal characters. Please enter a valid username.', $errors['username'] );
@@ -1257,7 +1257,7 @@ public function test_create_item_illegal_username() {
 		$this->assertErrorResponse( 'rest_invalid_param', $response, 400 );
 
 		$data = $response->get_data();
-		$this->assertInternalType( 'array', $data['data']['params'] );
+		$this->assertIsArray( $data['data']['params'] );
 		$errors = $data['data']['params'];
 		$this->assertInternalType( 'string', $errors['username'] );
 		$this->assertEquals( 'Sorry, that username is not allowed.', $errors['username'] );
@@ -1381,7 +1381,7 @@ public function test_create_existing_network_user_on_sub_site_has_error() {
 
 		$this->assertErrorResponse( 'rest_invalid_param', $switched_response, 400 );
 		$data = $switched_response->get_data();
-		$this->assertInternalType( 'array', $data['additional_errors'] );
+		$this->assertIsArray( $data['additional_errors'] );
 		$this->assertCount( 2, $data['additional_errors'] );
 		$errors = $data['additional_errors'];
 		foreach ( $errors as $error ) {
diff --git a/tests/phpunit/tests/rewrite.php b/tests/phpunit/tests/rewrite.php
index bb01ae8d805d..e4e140e0a6d6 100644
--- a/tests/phpunit/tests/rewrite.php
+++ b/tests/phpunit/tests/rewrite.php
@@ -482,7 +482,7 @@ public function test_flush_rules_does_not_delete_option() {
 		$this->set_permalink_structure( '/%year%/%monthnum%/%day%/%postname%/' );
 
 		$rewrite_rules = get_option( 'rewrite_rules' );
-		$this->assertInternalType( 'array', $rewrite_rules );
+		$this->assertIsArray( $rewrite_rules );
 		$this->assertNotEmpty( $rewrite_rules );
 	}
 }
diff --git a/tests/phpunit/tests/rewrite/permastructs.php b/tests/phpunit/tests/rewrite/permastructs.php
index 859af86cc619..8a528ef3cc84 100644
--- a/tests/phpunit/tests/rewrite/permastructs.php
+++ b/tests/phpunit/tests/rewrite/permastructs.php
@@ -34,7 +34,7 @@ public function test_remove_permastruct() {
 		global $wp_rewrite;
 
 		add_permastruct( 'foo', 'bar/%foo%' );
-		$this->assertInternalType( 'array', $wp_rewrite->extra_permastructs['foo'] );
+		$this->assertIsArray( $wp_rewrite->extra_permastructs['foo'] );
 		$this->assertSame( '/bar/%foo%', $wp_rewrite->extra_permastructs['foo']['struct'] );
 
 		remove_permastruct( 'foo' );
diff --git a/tests/phpunit/tests/taxonomy.php b/tests/phpunit/tests/taxonomy.php
index e8fcffc8d9da..a6fd7e04ed28 100644
--- a/tests/phpunit/tests/taxonomy.php
+++ b/tests/phpunit/tests/taxonomy.php
@@ -840,7 +840,7 @@ public function test_unregister_taxonomy_removes_permastruct() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $wp_rewrite->extra_permastructs['foo'] );
+		$this->assertIsArray( $wp_rewrite->extra_permastructs['foo'] );
 		$this->assertTrue( unregister_taxonomy( 'foo' ) );
 		$this->assertFalse( isset( $wp_rewrite->extra_permastructs['foo'] ) );
 	}
diff --git a/tests/phpunit/tests/term.php b/tests/phpunit/tests/term.php
index 08c08f8a7c9e..87a3d950156d 100644
--- a/tests/phpunit/tests/term.php
+++ b/tests/phpunit/tests/term.php
@@ -53,7 +53,7 @@ function test_is_term_type() {
 		// Insert a term.
 		$term = rand_str();
 		$t    = wp_insert_term( $term, $this->taxonomy );
-		$this->assertInternalType( 'array', $t );
+		$this->assertIsArray( $t );
 		$term_obj = get_term_by( 'name', $term, $this->taxonomy );
 		$this->assertEquals( $t['term_id'], term_exists( $term_obj->slug ) );
 
@@ -109,9 +109,9 @@ function test_term_is_ancestor_of() {
 		$term2 = rand_str();
 
 		$t = wp_insert_term( $term, 'category' );
-		$this->assertInternalType( 'array', $t );
+		$this->assertIsArray( $t );
 		$t2 = wp_insert_term( $term, 'category', array( 'parent' => $t['term_id'] ) );
-		$this->assertInternalType( 'array', $t2 );
+		$this->assertIsArray( $t2 );
 		if ( function_exists( 'term_is_ancestor_of' ) ) {
 			$this->assertTrue( term_is_ancestor_of( $t['term_id'], $t2['term_id'], 'category' ) );
 			$this->assertFalse( term_is_ancestor_of( $t2['term_id'], $t['term_id'], 'category' ) );
@@ -153,7 +153,7 @@ function test_wp_set_post_categories() {
 		$post_id = self::$post_ids[0];
 		$post    = get_post( $post_id );
 
-		$this->assertInternalType( 'array', $post->post_category );
+		$this->assertIsArray( $post->post_category );
 		$this->assertEquals( 1, count( $post->post_category ) );
 		$this->assertEquals( get_option( 'default_category' ), $post->post_category[0] );
 
diff --git a/tests/phpunit/tests/term/getTerm.php b/tests/phpunit/tests/term/getTerm.php
index 15052589c14c..5d557bf3d02e 100644
--- a/tests/phpunit/tests/term/getTerm.php
+++ b/tests/phpunit/tests/term/getTerm.php
@@ -103,14 +103,14 @@ public function test_output_object() {
 	public function test_output_array_a() {
 		$t    = self::factory()->term->create( array( 'taxonomy' => 'wptests_tax' ) );
 		$term = get_term( $t, 'wptests_tax', ARRAY_A );
-		$this->assertInternalType( 'array', $term );
+		$this->assertIsArray( $term );
 		$this->assertTrue( isset( $term['term_id'] ) );
 	}
 
 	public function test_output_array_n() {
 		$t    = self::factory()->term->create( array( 'taxonomy' => 'wptests_tax' ) );
 		$term = get_term( $t, 'wptests_tax', ARRAY_N );
-		$this->assertInternalType( 'array', $term );
+		$this->assertIsArray( $term );
 		$this->assertFalse( isset( $term['term_id'] ) );
 		foreach ( $term as $k => $v ) {
 			$this->assertInternalType( 'integer', $k );
diff --git a/tests/phpunit/tests/term/getTerms.php b/tests/phpunit/tests/term/getTerms.php
index e996cffdbd5d..48d80138ff53 100644
--- a/tests/phpunit/tests/term/getTerms.php
+++ b/tests/phpunit/tests/term/getTerms.php
@@ -861,7 +861,7 @@ function test_get_term_children_recursion() {
 		$term = get_term( $term['term_id'], 'category' );
 
 		$this->assertEquals( $term->term_id, $term->parent );
-		$this->assertInternalType( 'array', get_term_children( $term->term_id, 'category' ) );
+		$this->assertIsArray( get_term_children( $term->term_id, 'category' ) );
 
 		add_filter( 'wp_update_term_parent', 'wp_check_term_hierarchy_for_loops', 10, 3 );
 	}
diff --git a/tests/phpunit/tests/term/getTheTerms.php b/tests/phpunit/tests/term/getTheTerms.php
index 54450a7c8125..86cc2fb8c133 100644
--- a/tests/phpunit/tests/term/getTheTerms.php
+++ b/tests/phpunit/tests/term/getTheTerms.php
@@ -39,7 +39,7 @@ function test_object_term_cache() {
 		// get_the_terms() does prime the cache.
 		$terms = get_the_terms( $post_id, $this->taxonomy );
 		$cache = wp_cache_get( $post_id, $this->taxonomy . '_relationships' );
-		$this->assertInternalType( 'array', $cache );
+		$this->assertIsArray( $cache );
 
 		// Cache should be empty after a set.
 		$tt_2 = wp_set_object_terms( $post_id, $terms_2, $this->taxonomy );
diff --git a/tests/phpunit/tests/term/termExists.php b/tests/phpunit/tests/term/termExists.php
index 27aa2791df64..d963e793ba94 100644
--- a/tests/phpunit/tests/term/termExists.php
+++ b/tests/phpunit/tests/term/termExists.php
@@ -116,7 +116,7 @@ public function test_term_exists_taxonomy_nonempty_parent_nonempty_match_slug()
 
 		_unregister_taxonomy( 'foo' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertEquals( $t, $found['term_id'] );
 	}
 
@@ -180,7 +180,7 @@ public function test_term_exists_taxonomy_nonempty_parent_nonempty_match_name()
 
 		_unregister_taxonomy( 'foo' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertEquals( $t, $found['term_id'] );
 	}
 
@@ -198,7 +198,7 @@ public function test_term_exists_taxonomy_nonempty_parent_empty_match_slug() {
 
 		_unregister_taxonomy( 'foo' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertEquals( $t, $found['term_id'] );
 	}
 
@@ -216,7 +216,7 @@ public function test_term_exists_taxonomy_nonempty_parent_empty_match_name() {
 
 		_unregister_taxonomy( 'foo' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertEquals( $t, $found['term_id'] );
 	}
 
@@ -262,7 +262,7 @@ function test_term_exists_known() {
 		// Insert a term.
 		$term = rand_str();
 		$t    = wp_insert_term( $term, 'wptests_tax' );
-		$this->assertInternalType( 'array', $t );
+		$this->assertIsArray( $t );
 		$this->assertEquals( $t['term_id'], term_exists( $t['term_id'] ) );
 		$this->assertEquals( $t['term_id'], term_exists( $term ) );
 
diff --git a/tests/phpunit/tests/term/wpGenerateTagCloud.php b/tests/phpunit/tests/term/wpGenerateTagCloud.php
index 72584dcef1ee..50597f67d9a1 100644
--- a/tests/phpunit/tests/term/wpGenerateTagCloud.php
+++ b/tests/phpunit/tests/term/wpGenerateTagCloud.php
@@ -106,7 +106,7 @@ function test_hide_empty_false_format_array() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertStringContainsString( '>' . $tags[0]->name . '<', $found[0] );
 	}
 
diff --git a/tests/phpunit/tests/term/wpInsertTerm.php b/tests/phpunit/tests/term/wpInsertTerm.php
index 7a491f585436..401225f444d2 100644
--- a/tests/phpunit/tests/term/wpInsertTerm.php
+++ b/tests/phpunit/tests/term/wpInsertTerm.php
@@ -27,7 +27,7 @@ public function test_wp_insert_delete_term() {
 		$initial_count = wp_count_terms( $taxonomy );
 
 		$t = wp_insert_term( $term, $taxonomy );
-		$this->assertInternalType( 'array', $t );
+		$this->assertIsArray( $t );
 		$this->assertNotWPError( $t );
 		$this->assertTrue( $t['term_id'] > 0 );
 		$this->assertTrue( $t['term_taxonomy_id'] > 0 );
@@ -776,7 +776,7 @@ public function test_wp_insert_term_should_return_term_id_and_term_taxonomy_id()
 
 		_unregister_taxonomy( 'wptests_tax' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertNotEmpty( $found['term_id'] );
 		$this->assertNotEmpty( $found['term_taxonomy_id'] );
 		$this->assertNotEmpty( $term_by_id );
@@ -902,7 +902,7 @@ public function test_wp_insert_term_with_null_description() {
 	public function deleted_term_cb( $term, $tt_id, $taxonomy, $deleted_term, $object_ids ) {
 		$this->assertInternalType( 'object', $deleted_term );
 		$this->assertInternalType( 'int', $term );
-		$this->assertInternalType( 'array', $object_ids );
+		$this->assertIsArray( $object_ids );
 		// Pesky string $this->assertInternalType( 'int', $tt_id );
 		$this->assertEquals( $term, $deleted_term->term_id );
 		$this->assertEquals( $taxonomy, $deleted_term->taxonomy );
diff --git a/tests/phpunit/tests/term/wpSetObjectTerms.php b/tests/phpunit/tests/term/wpSetObjectTerms.php
index c3d146b34d31..c510ed9a801a 100644
--- a/tests/phpunit/tests/term/wpSetObjectTerms.php
+++ b/tests/phpunit/tests/term/wpSetObjectTerms.php
@@ -106,7 +106,7 @@ function test_set_object_terms_by_id() {
 		for ( $i = 0; $i < 3; $i++ ) {
 			$term   = "term_{$i}";
 			$result = wp_insert_term( $term, $this->taxonomy );
-			$this->assertInternalType( 'array', $result );
+			$this->assertIsArray( $result );
 			$term_id[ $term ] = $result['term_id'];
 		}
 
@@ -254,7 +254,7 @@ function test_change_object_terms_by_id() {
 		for ( $i = 0; $i < 3; $i++ ) {
 			$term   = "term_{$i}";
 			$result = wp_insert_term( $term, $this->taxonomy );
-			$this->assertInternalType( 'array', $result );
+			$this->assertIsArray( $result );
 			$terms_1[ $i ] = $result['term_id'];
 		}
 
diff --git a/tests/phpunit/tests/term/wpUpdateTerm.php b/tests/phpunit/tests/term/wpUpdateTerm.php
index 5de6d83c599a..0797d4ab0676 100644
--- a/tests/phpunit/tests/term/wpUpdateTerm.php
+++ b/tests/phpunit/tests/term/wpUpdateTerm.php
@@ -612,7 +612,7 @@ public function test_wp_update_term_should_return_term_id_and_term_taxonomy_id()
 
 		_unregister_taxonomy( 'wptests_tax' );
 
-		$this->assertInternalType( 'array', $found );
+		$this->assertIsArray( $found );
 		$this->assertNotEmpty( $found['term_id'] );
 		$this->assertNotEmpty( $found['term_taxonomy_id'] );
 		$this->assertNotEmpty( $term_by_id );
diff --git a/tests/phpunit/tests/theme/getThemeStarterContent.php b/tests/phpunit/tests/theme/getThemeStarterContent.php
index b4ff34cdafc1..9a21027d6c99 100644
--- a/tests/phpunit/tests/theme/getThemeStarterContent.php
+++ b/tests/phpunit/tests/theme/getThemeStarterContent.php
@@ -142,17 +142,17 @@ function test_default_content_sections() {
 		$this->assertSame( $dehydrated_starter_content['attachments']['featured-image-logo'], $hydrated_starter_content['attachments']['featured-image-logo'] );
 
 		foreach ( $hydrated_starter_content['widgets']['sidebar-1'] as $widget ) {
-			$this->assertInternalType( 'array', $widget );
+			$this->assertIsArray( $widget );
 			$this->assertCount( 2, $widget );
 			$this->assertInternalType( 'string', $widget[0] );
-			$this->assertInternalType( 'array', $widget[1] );
+			$this->assertIsArray( $widget[1] );
 			$this->assertArrayHasKey( 'title', $widget[1] );
 		}
 		$this->assertEquals( 'text', $hydrated_starter_content['widgets']['sidebar-1'][1][0], 'Core content extended' );
 		$this->assertEquals( 'Our Story', $hydrated_starter_content['widgets']['sidebar-1'][1][1]['title'], 'Core content extended' );
 
 		foreach ( $hydrated_starter_content['nav_menus']['top']['items'] as $nav_menu_item ) {
-			$this->assertInternalType( 'array', $nav_menu_item );
+			$this->assertIsArray( $nav_menu_item );
 			$this->assertTrue( ! empty( $nav_menu_item['object_id'] ) || ! empty( $nav_menu_item['url'] ) );
 		}
 		$this->assertEquals( 'Email Us', $hydrated_starter_content['nav_menus']['top']['items'][4]['title'], 'Core content extended' );
@@ -160,7 +160,7 @@ function test_default_content_sections() {
 		foreach ( $hydrated_starter_content['posts'] as $key => $post ) {
 			$this->assertInternalType( 'string', $key );
 			$this->assertFalse( is_numeric( $key ) );
-			$this->assertInternalType( 'array', $post );
+			$this->assertIsArray( $post );
 			$this->assertArrayHasKey( 'post_type', $post );
 			$this->assertArrayHasKey( 'post_title', $post );
 		}
@@ -200,7 +200,7 @@ function test_get_theme_starter_content_filter() {
 	 * @return array Filtered starter content.
 	 */
 	public function filter_theme_starter_content( $content, $config ) {
-		$this->assertInternalType( 'array', $config );
+		$this->assertIsArray( $config );
 		$this->assertCount( 1, $config['widgets']['sidebar-1'] );
 		$content['widgets']['sidebar-1'][] = array(
 			'text',
diff --git a/tests/phpunit/tests/widgets.php b/tests/phpunit/tests/widgets.php
index a7e16df59a3f..273ee6180293 100644
--- a/tests/phpunit/tests/widgets.php
+++ b/tests/phpunit/tests/widgets.php
@@ -538,7 +538,7 @@ function test_wp_widget_get_settings() {
 		$this->assertEquals( 1, $option_value['_multiwidget'] );
 		$this->assertArrayHasKey( 2, $option_value );
 		$instance = $option_value[2];
-		$this->assertInternalType( 'array', $instance );
+		$this->assertIsArray( $instance );
 		$this->assertArrayHasKey( 'title', $instance );
 		unset( $option_value['_multiwidget'] );
 
@@ -772,11 +772,11 @@ function test_retrieve_widgets_with_theme_mod() {
 
 		$result = retrieve_widgets( true );
 
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $result, $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		$this->assertContains( 'tag_cloud-1', $sidebars_widgets['sidebar-1'] );
@@ -822,11 +822,11 @@ function test_retrieve_widgets_with_sidebars_widgets_matching_registered_sidebar
 		$result = retrieve_widgets( true );
 
 		// $sidebars_widgets matches registered sidebars.
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $result, $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		$this->assertContains( 'tag_cloud-1', $sidebars_widgets['sidebar-1'] );
@@ -861,11 +861,11 @@ function test_retrieve_widgets_with_sidebars_widgets_not_matching_registered_sid
 		$result = retrieve_widgets( true );
 
 		$_wp_sidebars_widgets = array();
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $result, $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		// Current theme doesn't have a fantasy-sidebar.
@@ -904,11 +904,11 @@ function test_retrieve_widgets_with_sidebars_widgets_not_matching_registered_sid
 		$result = retrieve_widgets();
 
 		$_wp_sidebars_widgets = array();
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $result, $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		// This sidebar is not registered anymore.
@@ -956,11 +956,11 @@ function test_retrieve_widgets_for_customizer() {
 		$result = retrieve_widgets( 'customize' );
 
 		$_wp_sidebars_widgets = array();
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $result, $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		$this->assertContains( 'tag_cloud-1', $sidebars_widgets['sidebar-1'] );
@@ -1025,10 +1025,10 @@ function test_retrieve_widgets_move_orphaned_widgets_to_inactive() {
 
 		retrieve_widgets();
 
-		$this->assertInternalType( 'array', $sidebars_widgets );
+		$this->assertIsArray( $sidebars_widgets );
 
 		foreach ( $sidebars_widgets as $widgets ) {
-			$this->assertInternalType( 'array', $widgets );
+			$this->assertIsArray( $widgets );
 		}
 
 		// 6 default widgets + 1 orphaned calendar widget = 7.
@@ -1058,7 +1058,7 @@ public function test__wp_remove_unregistered_widgets() {
 
 		$filtered_widgets = _wp_remove_unregistered_widgets( $widgets, $allowed_widgets );
 
-		$this->assertInternalType( 'array', $filtered_widgets );
+		$this->assertIsArray( $filtered_widgets );
 		$this->assertArrayHasKey( 'fantasy', $filtered_widgets );
 		$this->assertEmpty( $filtered_widgets['fantasy'] );
 		$this->assertArrayHasKey( 'array_version', $filtered_widgets );
diff --git a/tests/phpunit/tests/widgets/media-widget.php b/tests/phpunit/tests/widgets/media-widget.php
index 68cc2e19c032..aa7ef6f3fb79 100644
--- a/tests/phpunit/tests/widgets/media-widget.php
+++ b/tests/phpunit/tests/widgets/media-widget.php
@@ -219,7 +219,7 @@ function test_get_instance_schema() {
 		$this->filter_instance_schema_args = null;
 		add_filter( 'widget_mocked_instance_schema', array( $this, 'filter_instance_schema' ), 10, 2 );
 		$schema = $widget->get_instance_schema();
-		$this->assertInternalType( 'array', $this->filter_instance_schema_args );
+		$this->assertIsArray( $this->filter_instance_schema_args );
 		$this->assertSame( $widget, $this->filter_instance_schema_args['widget'] );
 		$this->assertEqualSets( array( 'attachment_id', 'title', 'url' ), array_keys( $this->filter_instance_schema_args['schema'] ) );
 		$this->assertArrayHasKey( 'injected', $schema );
diff --git a/tests/phpunit/tests/xmlrpc/mw/getPost.php b/tests/phpunit/tests/xmlrpc/mw/getPost.php
index 9c914d708eeb..2c9c66039b71 100644
--- a/tests/phpunit/tests/xmlrpc/mw/getPost.php
+++ b/tests/phpunit/tests/xmlrpc/mw/getPost.php
@@ -58,7 +58,7 @@ function test_valid_post() {
 		$this->assertInternalType( 'string', $result['title'] );
 		$this->assertInternalType( 'string', $result['link'] );
 		$this->assertInternalType( 'string', $result['permaLink'] );
-		$this->assertInternalType( 'array', $result['categories'] );
+		$this->assertIsArray( $result['categories'] );
 		$this->assertInternalType( 'string', $result['mt_excerpt'] );
 		$this->assertInternalType( 'string', $result['mt_text_more'] );
 		$this->assertInternalType( 'string', $result['wp_more_text'] );
@@ -70,7 +70,7 @@ function test_valid_post() {
 		$this->assertInternalType( 'string', $result['wp_author_id'] );
 		$this->assertInternalType( 'string', $result['wp_author_display_name'] );
 		$this->assertInternalType( 'string', $result['post_status'] );
-		$this->assertInternalType( 'array', $result['custom_fields'] );
+		$this->assertIsArray( $result['custom_fields'] );
 		$this->assertInternalType( 'string', $result['wp_post_format'] );
 		$this->assertInternalType( 'bool', $result['sticky'] );
 
diff --git a/tests/phpunit/tests/xmlrpc/mw/getRecentPosts.php b/tests/phpunit/tests/xmlrpc/mw/getRecentPosts.php
index 06350d00e1af..c20e81f7248f 100644
--- a/tests/phpunit/tests/xmlrpc/mw/getRecentPosts.php
+++ b/tests/phpunit/tests/xmlrpc/mw/getRecentPosts.php
@@ -64,7 +64,7 @@ function test_valid_post() {
 			$this->assertInternalType( 'string', $result['title'] );
 			$this->assertInternalType( 'string', $result['link'] );
 			$this->assertInternalType( 'string', $result['permaLink'] );
-			$this->assertInternalType( 'array', $result['categories'] );
+			$this->assertIsArray( $result['categories'] );
 			$this->assertInternalType( 'string', $result['mt_excerpt'] );
 			$this->assertInternalType( 'string', $result['mt_text_more'] );
 			$this->assertInternalType( 'string', $result['wp_more_text'] );
@@ -76,7 +76,7 @@ function test_valid_post() {
 			$this->assertInternalType( 'string', $result['wp_author_id'] );
 			$this->assertInternalType( 'string', $result['wp_author_display_name'] );
 			$this->assertInternalType( 'string', $result['post_status'] );
-			$this->assertInternalType( 'array', $result['custom_fields'] );
+			$this->assertIsArray( $result['custom_fields'] );
 			$this->assertInternalType( 'string', $result['wp_post_format'] );
 
 			// Check expected values.
diff --git a/tests/phpunit/tests/xmlrpc/wp/editPost.php b/tests/phpunit/tests/xmlrpc/wp/editPost.php
index 45ce7d6edf12..032d283cfdea 100644
--- a/tests/phpunit/tests/xmlrpc/wp/editPost.php
+++ b/tests/phpunit/tests/xmlrpc/wp/editPost.php
@@ -159,7 +159,7 @@ function test_post_thumbnail() {
 		$result = $this->myxmlrpcserver->wp_getPost( array( 1, 'author', 'author', $post_id ) );
 		$this->assertNotIXRError( $result );
 		$this->assertArrayHasKey( 'post_thumbnail', $result );
-		$this->assertInternalType( 'array', $result['post_thumbnail'] );
+		$this->assertIsArray( $result['post_thumbnail'] );
 		$this->assertEquals( $attachment_id, $result['post_thumbnail']['attachment_id'] );
 
 		// Edit the post without supplying a post_thumbnail and check that it didn't change.
diff --git a/tests/phpunit/tests/xmlrpc/wp/getComments.php b/tests/phpunit/tests/xmlrpc/wp/getComments.php
index b3b1d03e3a44..1f861a7045ea 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getComments.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getComments.php
@@ -198,7 +198,7 @@ function test_author_capabilities() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $result2 );
+		$this->assertIsArray( $result2 );
 		$this->assertCount( 1, $result2 );
 
 		$result3 = $this->myxmlrpcserver->wp_getComments(
@@ -225,7 +225,7 @@ function test_author_capabilities() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $result4 );
+		$this->assertIsArray( $result4 );
 		$this->assertCount( 1, $result4 );
 	}
 
@@ -276,7 +276,7 @@ function test_editor_capabilities() {
 				),
 			)
 		);
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertCount( 1, $result );
 
 		$result2 = $this->myxmlrpcserver->wp_getComments(
@@ -291,7 +291,7 @@ function test_editor_capabilities() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $result2 );
+		$this->assertIsArray( $result2 );
 		$this->assertCount( 1, $result2 );
 	}
 }
diff --git a/tests/phpunit/tests/xmlrpc/wp/getMediaItem.php b/tests/phpunit/tests/xmlrpc/wp/getMediaItem.php
index 41f0eded1fde..746761bb9ac6 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getMediaItem.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getMediaItem.php
@@ -58,7 +58,7 @@ function test_valid_media_item() {
 		$this->assertInternalType( 'string', $result['description'] );
 		$this->assertInternalType( 'string', $result['link'] );
 		$this->assertInternalType( 'string', $result['thumbnail'] );
-		$this->assertInternalType( 'array', $result['metadata'] );
+		$this->assertIsArray( $result['metadata'] );
 
 		// Check expected values.
 		$this->assertStringMatchesFormat( '%d', $result['attachment_id'] );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getOptions.php b/tests/phpunit/tests/xmlrpc/wp/getOptions.php
index 59b3636b3c4e..fc3db750b8a4 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getOptions.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getOptions.php
@@ -15,7 +15,7 @@ function test_valid_username_password() {
 		$this->make_user_by_role( 'subscriber' );
 
 		$result = $this->myxmlrpcserver->wp_getOptions( array( 1, 'subscriber', 'subscriber' ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 'WordPress', $result['software_name']['value'] );
 	}
 
@@ -23,7 +23,7 @@ function test_option_value() {
 		$this->make_user_by_role( 'administrator' );
 
 		$result = $this->myxmlrpcserver->wp_getOptions( array( 1, 'administrator', 'administrator', 'default_comment_status' ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 
 		$this->assertEquals( get_option( 'default_comment_status' ), $result['default_comment_status']['value'] );
 		$this->assertFalse( $result['default_comment_status']['readonly'] );
@@ -37,7 +37,7 @@ function test_option_values_subscriber() {
 		$this->make_user_by_role( 'subscriber' );
 
 		$result = $this->myxmlrpcserver->wp_getOptions( array( 1, 'subscriber', 'subscriber' ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 
 		// Read-only options.
 		$this->assertEquals( 'WordPress', $result['software_name']['value'] );
@@ -126,7 +126,7 @@ function test_option_values_admin() {
 		$this->make_user_by_role( 'administrator' );
 
 		$result = $this->myxmlrpcserver->wp_getOptions( array( 1, 'administrator', 'administrator' ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 
 		// Read-only options.
 		$this->assertEquals( 'WordPress', $result['software_name']['value'] );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getPage.php b/tests/phpunit/tests/xmlrpc/wp/getPage.php
index 7991f5568d6f..061e6a2f1221 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getPage.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getPage.php
@@ -53,7 +53,7 @@ function test_valid_page() {
 		$this->assertInternalType( 'string', $result['title'] );
 		$this->assertInternalType( 'string', $result['link'] );
 		$this->assertInternalType( 'string', $result['permaLink'] );
-		$this->assertInternalType( 'array', $result['categories'] );
+		$this->assertIsArray( $result['categories'] );
 		$this->assertInternalType( 'string', $result['excerpt'] );
 		$this->assertInternalType( 'string', $result['text_more'] );
 		$this->assertInternalType( 'int', $result['mt_allow_comments'] );
@@ -66,7 +66,7 @@ function test_valid_page() {
 		$this->assertInternalType( 'int', $result['wp_page_order'] );
 		$this->assertInternalType( 'string', $result['wp_author_id'] );
 		$this->assertInternalType( 'string', $result['wp_author_display_name'] );
-		$this->assertInternalType( 'array', $result['custom_fields'] );
+		$this->assertIsArray( $result['custom_fields'] );
 		$this->assertInternalType( 'string', $result['wp_page_template'] );
 
 		$post_data = get_post( self::$post_id );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getPost.php b/tests/phpunit/tests/xmlrpc/wp/getPost.php
index 1d0e01afcc82..06fa1e47418f 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getPost.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getPost.php
@@ -60,8 +60,8 @@ function test_valid_post() {
 		$this->assertInternalType( 'string', $result['ping_status'] );
 		$this->assertInternalType( 'bool', $result['sticky'] );
 		$this->assertInternalType( 'string', $result['post_format'] );
-		$this->assertInternalType( 'array', $result['post_thumbnail'] );
-		$this->assertInternalType( 'array', $result['custom_fields'] );
+		$this->assertIsArray( $result['post_thumbnail'] );
+		$this->assertIsArray( $result['custom_fields'] );
 
 		// Check expected values.
 		$this->assertStringMatchesFormat( '%d', $result['post_id'] );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getPostType.php b/tests/phpunit/tests/xmlrpc/wp/getPostType.php
index d62f426d1453..5c126e67a34e 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getPostType.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getPostType.php
@@ -75,10 +75,10 @@ function test_valid_type() {
 		$this->assertInternalType( 'bool', $result['show_ui'] );
 		$this->assertInternalType( 'int', $result['menu_position'] );
 		$this->assertInternalType( 'string', $result['menu_icon'] );
-		$this->assertInternalType( 'array', $result['labels'] );
-		$this->assertInternalType( 'array', $result['cap'] );
-		$this->assertInternalType( 'array', $result['taxonomies'] );
-		$this->assertInternalType( 'array', $result['supports'] );
+		$this->assertIsArray( $result['labels'] );
+		$this->assertIsArray( $result['cap'] );
+		$this->assertIsArray( $result['taxonomies'] );
+		$this->assertIsArray( $result['supports'] );
 
 		// Check label data types.
 		$this->assertInternalType( 'string', $result['labels']['name'] );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getPostTypes.php b/tests/phpunit/tests/xmlrpc/wp/getPostTypes.php
index 20f1092574a4..ae80d4e8e82b 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getPostTypes.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getPostTypes.php
@@ -15,7 +15,7 @@ function test_incapable_user() {
 
 		$result = $this->myxmlrpcserver->wp_getPostTypes( array( 1, 'subscriber', 'subscriber' ) );
 		$this->assertNotIXRError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( 0, count( $result ) );
 	}
 
@@ -24,7 +24,7 @@ function test_capable_user() {
 
 		$result = $this->myxmlrpcserver->wp_getPostTypes( array( 1, 'editor', 'editor' ) );
 		$this->assertNotIXRError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertGreaterThan( 0, count( $result ) );
 	}
 
@@ -33,7 +33,7 @@ function test_simple_filter() {
 
 		$result = $this->myxmlrpcserver->wp_getPostTypes( array( 1, 'editor', 'editor', array( 'hierarchical' => true ) ) );
 		$this->assertNotIXRError( $result );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 
 		// Verify that page is in the result, and post is not.
 		$result_names = wp_list_pluck( $result, 'name' );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getRevisions.php b/tests/phpunit/tests/xmlrpc/wp/getRevisions.php
index 15b9287d757f..52b8572449a9 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getRevisions.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getRevisions.php
@@ -41,7 +41,7 @@ function test_revision_count() {
 		); // Create the initial revision.
 
 		$result = $this->myxmlrpcserver->wp_getRevisions( array( 1, 'editor', 'editor', $post_id ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertCount( 1, $result );
 
 		wp_insert_post(
@@ -52,7 +52,7 @@ function test_revision_count() {
 		);
 
 		$result = $this->myxmlrpcserver->wp_getRevisions( array( 1, 'editor', 'editor', $post_id ) );
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertCount( 2, $result );
 	}
 
diff --git a/tests/phpunit/tests/xmlrpc/wp/getTerm.php b/tests/phpunit/tests/xmlrpc/wp/getTerm.php
index 35910f6f5d3b..190725c3b872 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getTerm.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getTerm.php
@@ -121,7 +121,7 @@ public function test_get_term_meta() {
 		);
 		$this->assertNotIXRError( $result );
 
-		$this->assertInternalType( 'array', $result['custom_fields'] );
+		$this->assertIsArray( $result['custom_fields'] );
 		$term_meta = get_term_meta( self::$term_id, '', true );
 		$this->assertEquals( $term_meta['foo'][0], $result['custom_fields'][0]['value'] );
 	}
diff --git a/tests/phpunit/tests/xmlrpc/wp/getTerms.php b/tests/phpunit/tests/xmlrpc/wp/getTerms.php
index 0dca65e409c0..751b6c0c8756 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getTerms.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getTerms.php
@@ -51,7 +51,7 @@ function test_valid_terms() {
 			$this->assertInternalType( 'int', $term['count'] );
 
 			// Check custom term meta.
-			$this->assertInternalType( 'array', $term['custom_fields'] );
+			$this->assertIsArray( $term['custom_fields'] );
 
 			// We expect all other IDs to be strings, not integers,
 			// so we don't return something larger than an XMLRPC integer can describe.
diff --git a/tests/phpunit/tests/xmlrpc/wp/getUser.php b/tests/phpunit/tests/xmlrpc/wp/getUser.php
index d46424b644ca..bbb94e32f612 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getUser.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getUser.php
@@ -88,7 +88,7 @@ function test_valid_user() {
 		$this->assertInternalType( 'string', $result['nicename'] );
 		$this->assertInternalType( 'string', $result['url'] );
 		$this->assertInternalType( 'string', $result['display_name'] );
-		$this->assertInternalType( 'array', $result['roles'] );
+		$this->assertIsArray( $result['roles'] );
 
 		// Check expected values.
 		$this->assertEquals( $user_id, $result['user_id'] );
diff --git a/tests/phpunit/tests/xmlrpc/wp/getUsers.php b/tests/phpunit/tests/xmlrpc/wp/getUsers.php
index 412a13b36418..34ab25f3550d 100644
--- a/tests/phpunit/tests/xmlrpc/wp/getUsers.php
+++ b/tests/phpunit/tests/xmlrpc/wp/getUsers.php
@@ -39,7 +39,7 @@ function test_capable_user() {
 		$this->assertInternalType( 'string', $result[0]['nicename'] );
 		$this->assertInternalType( 'string', $result[0]['url'] );
 		$this->assertInternalType( 'string', $result[0]['display_name'] );
-		$this->assertInternalType( 'array', $result[0]['roles'] );
+		$this->assertIsArray( $result[0]['roles'] );
 	}
 
 	function test_invalid_role() {
diff --git a/tests/phpunit/tests/xmlrpc/wp/newPost.php b/tests/phpunit/tests/xmlrpc/wp/newPost.php
index 675a47577e11..c0f546e89a48 100644
--- a/tests/phpunit/tests/xmlrpc/wp/newPost.php
+++ b/tests/phpunit/tests/xmlrpc/wp/newPost.php
@@ -280,11 +280,11 @@ function test_terms() {
 		$this->make_user_by_role( 'editor' );
 
 		$tag1 = wp_create_tag( 'tag1' );
-		$this->assertInternalType( 'array', $tag1 );
+		$this->assertIsArray( $tag1 );
 		$tag2 = wp_create_tag( 'tag2' );
-		$this->assertInternalType( 'array', $tag2 );
+		$this->assertIsArray( $tag2 );
 		$tag3 = wp_create_tag( 'tag3' );
-		$this->assertInternalType( 'array', $tag3 );
+		$this->assertIsArray( $tag3 );
 
 		$post   = array(
 			'post_title' => 'Test',
diff --git a/tests/phpunit/tests/xmlrpc/wp/setOptions.php b/tests/phpunit/tests/xmlrpc/wp/setOptions.php
index 27ad135ddc7c..2843461fbfc1 100644
--- a/tests/phpunit/tests/xmlrpc/wp/setOptions.php
+++ b/tests/phpunit/tests/xmlrpc/wp/setOptions.php
@@ -26,7 +26,7 @@ function test_set_option_no_escape_strings() {
 			)
 		);
 
-		$this->assertInternalType( 'array', $result );
+		$this->assertIsArray( $result );
 		$this->assertEquals( $escaped_string_with_quote, $result['blog_title']['value'] );
 		$this->assertEquals( 'open', $result['default_comment_status']['value'] );
 	}