@SuppressWarnings("unchecked")
  public static List<Statement> getStatements(MethodNode method) {
    Statement code = method.getCode();
    if (!(code instanceof BlockStatement)) { // null or single statement
      BlockStatement block = new BlockStatement();
      if (code != null) block.addStatement(code);
      method.setCode(block);
    }
    return ((BlockStatement)method.getCode()).getStatements();
  }
Returns a list of statements of the given method. Modifications to the returned list
will affect the method's statements.

@param method a method (node)
@return a list of statements of the given method
spock-core/src/main/java/org/spockframework/compiler/AstUtil.java