Check for auto increment edge case, add test

Author: JanJakes

tests/WP_SQLite_Driver_Tests.php

@@ -3885,4 +3885,12 @@ public function testTimestampColumnNamedTimestamp() {
 			$results
 		);
 	}
+
+	public function testCompoundPrimaryKeyAndAutoincrementNotSupported(): void {
+		$this->expectException( WP_SQLite_Driver_Exception::class );
+		$this->expectExceptionMessage( 'Cannot combine AUTOINCREMENT and multiple primary keys in SQLite' );
+		$this->assertQuery(
+			'CREATE TABLE t1 (id1 INT AUTO_INCREMENT, id2 INT, PRIMARY KEY(id1, id2))'
+		);
+	}
 }

wp-includes/sqlite-ast/class-wp-sqlite-driver.php

@@ -2641,6 +2641,11 @@ private function get_sqlite_create_table_statement( string $table_name, ?string
 
 			if ( 'PRIMARY' === $info['INDEX_NAME'] ) {
 				if ( $has_autoincrement ) {
+					if ( count( $constraint ) > 1 ) {
+						throw $this->new_driver_exception(
+							'Cannot combine AUTOINCREMENT and multiple primary keys in SQLite'
+						);
+					}
 					continue;
 				}
 				$query  = '  PRIMARY KEY (';