Show lock deletion tip when core update fails with lock error

features/core-update.feature

@@ -384,3 +384,21 @@ Feature: Update WordPress core
       """
       Success:
       """
+
+  Scenario: Show helpful tip when update is locked
+    Given a WP install
+
+    When I run `wp option update core_updater.lock 100000000000000`
+    And I try `wp core update --version=trunk`
+    Then STDERR should contain:
+      """
+      Another update is currently in progress. You may need to run `wp option delete core_updater.lock` after verifying another update isn't actually running.
+      """
+    And the return code should be 1
+
+    # Clean up the lock
+    When I run `wp option delete core_updater.lock`
+    Then STDOUT should contain:
+      """
+      Success:
+      """

src/Core_Command.php

@@ -1234,7 +1234,12 @@ public function update( $args, $assoc_args ) {
 			if ( is_wp_error( $result ) ) {
 				$message = WP_CLI::error_to_string( $result );
 				if ( 'up_to_date' !== $result->get_error_code() ) {
-					WP_CLI::error( $message );
+					// Check if the error is related to the core_updater.lock
+					if ( self::is_lock_error( $result ) ) {
+						WP_CLI::error( rtrim( $message, '.' ) . '. You may need to run `wp option delete core_updater.lock` after verifying another update isn\'t actually running.' );
+					} else {
+						WP_CLI::error( $message );
+					}
 				} else {
 					WP_CLI::success( $message );
 				}
@@ -1663,4 +1668,21 @@ function () use ( $new_zip_file ) {
 			WP_CLI::error( 'ZipArchive failed to open ZIP file.' );
 		}
 	}
+
+	/**
+	 * Checks if a WP_Error is related to the core_updater.lock.
+	 *
+	 * @param \WP_Error $error The error object to check.
+	 * @return bool True if the error is related to the lock, false otherwise.
+	 */
+	private static function is_lock_error( $error ) {
+		// Check for the 'locked' error code used by WordPress Core
+		if ( 'locked' === $error->get_error_code() ) {
+			return true;
+		}
+
+		// Also check if the error message contains the lock text as a fallback
+		$message = WP_CLI::error_to_string( $error );
+		return false !== stripos( $message, 'another update is currently in progress' );
+	}
 }