This table structure:
CREATE TABLE t1 (id INT NOT NULL, PRIMARY KEY(id));
CREATE TABLE t2 (id INT NOT NULL, fk_id INT DEFAULT NULL);
ALTER TABLE t2 ADD FOREIGN KEY (fk_id) REFERENCES t1(id) ON DELETE SET NULL NOT DEFERRABLE INITIALLY IMMEDIATE;
will cause the listTableForeignKeys to produce incorrect results for the onDelete/Update constraints (the 'DEFAULT' or 'NULL' in 'SET DEFAULT' or 'SET NULL' respectively gets cut off).
This looks to be fixed in the main branch.