Fix: Aggressive global FOR UPDATE stripping and AS keyword support for Action Scheduler

Author: wp-fuse

.gitignore

@@ -7,3 +7,13 @@ composer.lock
 ._*
 /wordpress
 /.claude/settings.local.json
+
+# Local distribution and dev junk
+dist/
+grammar-tools/
+packages/
+tests/
+wp-setup.sh
+phpunit.xml.dist
+phpcs.xml.dist
+db.copy

integrations/plugin-compatibility/boot.php

@@ -21,17 +21,14 @@ function wp_sqlite_integration_plugin_compat( $query ) {
 		return $query;
 	}
 
-	// 1. Intercept known problematic queries and short-circuit if necessary.
-	// (Previously intercepted information_schema, but that broke WordPress Core Site Health).
-
-	// 2. Global fallback for FOR UPDATE / SKIP LOCKED / NOWAIT.
-	// This ensures the legacy driver natively ignores these locking constraints where SQLite faults.
-	// We use a non-destructive lookahead for whitespace, semicolon, comments, or LIMIT.
+	// 1. Heavy cleaning of unsupported MySQL locking clauses.
+	// SQLite doesn't support FOR UPDATE, SKIP LOCKED, or NOWAIT anywhere. 
+	// We strip these globally (case-insensitive, multi-line) to prevent syntax errors in subqueries.
 	if ( stripos( $query, 'FOR UPDATE' ) !== false ) {
-		$query = preg_replace( '/\s+FOR\s+UPDATE(?:\s+(?:SKIP\s+LOCKED|NOWAIT))?(?=\s*(?:;|\/\*|$|\s+LIMIT))/is', '', $query );
+		$query = preg_replace( '/\s+FOR\s+UPDATE(?:\s+(?:SKIP\s+LOCKED|NOWAIT))?\b/is', '', $query );
 	}
 
-	// 3. Action Scheduler specific compatibility fixes.
+	// 2. Action Scheduler specific compatibility fixes.
 	if ( stripos( $query, 'actionscheduler' ) !== false ) {
 		// Escape the 'group' keyword safely.
 		// Action Scheduler sometimes queries an unquoted `group` column.
@@ -40,11 +37,13 @@ function wp_sqlite_integration_plugin_compat( $query ) {
 		// Fix 'INSERT wp_actionscheduler...' syntax to include 'INTO'.
 		$query = preg_replace( '/INSERT\s+(?!INTO\s+)(wp_actionscheduler_[a-zA-Z0-9_]+)/i', 'INSERT INTO $1', $query );
 
-		// Fix 'UPDATE ... JOIN' syntax manually because SQLite requires an 'UPDATE ... FROM' abstraction.
-		$pattern = '/UPDATE\s+([^\s]+)\s+t1\s+JOIN\s*\((.*?)\)\s*t2\s*ON\s*t1\.action_id\s*=\s*t2\.action_id\s*SET\s*(.*)/is';
+		// Fix 'UPDATE ... JOIN' syntax manually.
+		// Handles variants like "UPDATE table t1 JOIN" and "UPDATE table AS t1 JOIN".
+		$pattern = '/UPDATE\s+([^\s]+)\s+(?:AS\s+)?t1\s+JOIN\s*\((.*?)\)\s*(?:AS\s+)?t2\s*ON\s*t1\.action_id\s*=\s*t2\.action_id\s*SET\s*(.*)/is';
 		if ( preg_match( $pattern, $query, $matches ) ) {
 			$set_clause = str_ireplace( 't1.', '', $matches[3] );
-			$query      = "UPDATE {$matches[1]} SET {$set_clause} WHERE action_id IN ({$matches[2]})";
+			// Extract the SELECT logic from the join to use in an IN clause.
+			$query = "UPDATE {$matches[1]} SET {$set_clause} WHERE action_id IN ({$matches[2]})";
 		}
 	}