Macro: SIGNALS

Documentation

Generates a pass if BODY signals a condition of type CONDITION. BODY is evaluated in a block named NIL, CONDITION is not evaluated.

Source

(defmacro signals (condition-spec
                   &body body)
  "Generates a pass if BODY signals a condition of type
CONDITION. BODY is evaluated in a block named NIL, CONDITION is
not evaluated."
  (let ((block-name (gensym)))
    (destructuring-bind (condition &optional reason-control reason-args)
        (ensure-list condition-spec)
      `(block ,block-name
         (handler-bind ((,condition (lambda (c)
                                      (declare (ignore c))
                                      ;; ok, body threw condition
                                      (add-result 'test-passed 
                                                  :test-expr ',condition)
                                      (return-from ,block-name t))))
           (block nil
             ,@body
             (process-failure
              :reason ,(if reason-control
                           `(format nil ,reason-control ,@reason-args)
                           `(format nil "Failed to signal a ~S" ',condition))
              :test-expr ',condition)
             (return-from ,block-name nil)))))))