Add method for finding relative WP major version

includes/Traits/Version_Utils.php

@@ -92,6 +92,25 @@ protected function get_php_recommended_version(): string {
 		return $recommended_version;
 	}
 
+	/**
+	 * Returns relative WordPress major version.
+	 *
+	 * @since 1.4.0
+	 *
+	 * @param string $version WordPress major version.
+	 * @param int    $steps   Steps to find relative version. Defaults to 1 for next major version.
+	 * @return string Relative WordPress major version.
+	 */
+	protected function get_wordpress_relative_major_version( string $version, int $steps = 1 ): string {
+		if ( 0 === $steps ) {
+			return $version;
+		}
+
+		$new_version = floatval( $version ) + ( 0.1 * $steps );
+
+		return (string) number_format( $new_version, 1 );
+	}
+
 	/**
 	 * Returns specific information.
 	 *

tests/phpunit/tests/Traits/Version_Utils_Tests.php

@@ -77,9 +77,32 @@ public function test_wordpress_recommended_php_version() {
 		$this->assertSame( '7.4', $version );
 	}
 
+	/**
+	 * @dataProvider data_wordpress_version_items
+	 */
+	public function test_wordpress_relative_major_version( $version, $steps, $new_version ) {
+		$result = $this->get_wordpress_relative_major_version( $version, $steps );
+		$this->assertSame( $new_version, $result );
+	}
+
 	public function tear_down() {
 		delete_transient( $this->info_transient_key );
 		delete_site_transient( $this->php_check_transient_key );
 		parent::tear_down();
 	}
+
+	public function data_wordpress_version_items() {
+		return array(
+			array( '6.7', 1, '6.8' ),
+			array( '6.7', -1, '6.6' ),
+			array( '6.7', 2, '6.9' ),
+			array( '6.7', -2, '6.5' ),
+			array( '5.9', 1, '6.0' ),
+			array( '6.0', -1, '5.9' ),
+			array( '5.9', 2, '6.1' ),
+			array( '6.0', -2, '5.8' ),
+			array( '5.8', 2, '6.0' ),
+			array( '6.1', -2, '5.9' ),
+		);
+	}
 }