diff --git a/tests/phpunit/tests/theme.php b/tests/phpunit/tests/theme.php
index 248aaa833a..c18c4d434f 100644
--- a/tests/phpunit/tests/theme.php
+++ b/tests/phpunit/tests/theme.php
@@ -302,36 +302,38 @@ class Tests_Theme extends WP_UnitTestCase {
 
 	/**
 	 * @ticket 48566
+	 *
+	 * @dataProvider data_year_in_readme
 	 */
-	public function test_year_in_readme() {
+	public function test_year_in_readme( $theme ) {
 		// This test is designed to only run on trunk.
 		$this->skipOnAutomatedBranches();
 
-		foreach ( $this->default_themes as $theme ) {
-			$wp_theme = wp_get_theme( $theme );
+		$wp_theme = wp_get_theme( $theme );
 
-			$path_to_readme_txt = $wp_theme->get_theme_root() . '/' . $wp_theme->get_stylesheet() . '/readme.txt';
-			$this->assertFileExists( $path_to_readme_txt );
+		$path_to_readme_txt = $wp_theme->get_theme_root() . '/' . $wp_theme->get_stylesheet() . '/readme.txt';
+		$this->assertFileExists( $path_to_readme_txt );
 
-			$readme    = file_get_contents( $path_to_readme_txt );
-			$this_year = gmdate( 'Y' );
+		$readme    = file_get_contents( $path_to_readme_txt );
+		$this_year = gmdate( 'Y' );
 
-			preg_match( '#Copyright (\d+) WordPress.org#', $readme, $matches );
-			if ( $matches ) {
-				$readme_year = trim( $matches[1] );
+		preg_match( '#(Copyright|\(C\)) (20\d\d-)?(\d+) WordPress.org#i', $readme, $matches );
+		if ( $matches ) {
+			$readme_year = trim( $matches[3] );
 
-				$this->assertSame( $this_year, $readme_year, "Bundled themes readme.txt's year needs to be updated to $this_year." );
-			}
-
-			preg_match( '#Copyright 20\d\d-(\d+) WordPress.org#', $readme, $matches );
-			if ( $matches ) {
-				$readme_year = trim( $matches[1] );
-
-				$this->assertSame( $this_year, $readme_year, "Bundled themes readme.txt's year needs to be updated to $this_year." );
-			}
+			$this->assertSame( $this_year, $readme_year, "$theme readme.txt's year needs to be updated to $this_year." );
 		}
 	}
 
+	public function data_year_in_readme() {
+		return array_map(
+			static function ( $theme ) {
+				return array( $theme );
+			},
+			$this->default_themes
+		);
+	}
+
 	/**
 	 * @ticket 20897
 	 * @expectedDeprecated get_theme_data