+;;;; miscellaneous side-effectful tests of the MOP
+
+;;;; This software is part of the SBCL system. See the README file for
+;;;; more information.
+;;;;
+;;;; While most of SBCL is derived from the CMU CL system, the test
+;;;; files (like this one) were written from scratch after the fork
+;;;; from CMU CL.
+;;;;
+;;;; This software is in the public domain and is provided with
+;;;; absolutely no warranty. See the COPYING and CREDITS files for
+;;;; more information.
+
+;;;; Note that the MOP is not in an entirely supported state.
+;;;; However, this seems a good a way as any of ensuring that we have
+;;;; no regressions.
+
+;;; This is basically the DYNAMIC-SLOT-CLASS example from AMOP, with
+;;; fixups for running in the full MOP rather than closette: SLOTDs
+;;; instead of slot-names, and so on.
+
+(defpackage "TEST" (:use "CL" "SB-MOP"))
+(in-package "TEST")
+
+(defclass dynamic-slot-class (standard-class) ())
+
+(defmethod validate-superclass
+ ((class dynamic-slot-class) (super standard-class))
+ t)
+
+(defmethod compute-effective-slot-definition
+ ((class dynamic-slot-class) name direct-slots)
+ (let ((slot (call-next-method)))
+ (setf (slot-definition-allocation slot) :dynamic)
+ slot))
+
+(defun dynamic-slot-p (slot)
+ (eq (slot-definition-allocation slot) :dynamic))
+
+(let ((table (make-hash-table)))
+
+ (defun allocate-table-entry (instance)
+ (setf (gethash instance table) ()))
+
+ (defun read-dynamic-slot-value (instance slot-name)
+ (let* ((alist (gethash instance table))
+ (entry (assoc slot-name alist)))
+ (if (null entry)
+ (error "slot ~S unbound in ~S" slot-name instance)
+ (cdr entry))))
+
+ (defun write-dynamic-slot-value (new-value instance slot-name)
+ (let* ((alist (gethash instance table))
+ (entry (assoc slot-name alist)))
+ (if (null entry)
+ (push `(,slot-name . ,new-value)
+ (gethash instance table))
+ (setf (cdr entry) new-value))
+ new-value))
+
+ (defun dynamic-slot-boundp (instance slot-name)
+ (let* ((alist (gethash instance table))
+ (entry (assoc slot-name alist)))
+ (not (null entry))))
+
+ (defun dynamic-slot-makunbound (instance slot-name)
+ (let* ((alist (gethash instance table))
+ (entry (assoc slot-name alist)))
+ (unless (null entry)
+ (setf (gethash instance table) (delete entry alist))))
+ instance)
+
+)
+
+(defmethod allocate-instance ((class dynamic-slot-class) &key)
+ (let ((instance (call-next-method)))
+ (allocate-table-entry instance)
+ instance))
+
+(defmethod slot-value-using-class ((class dynamic-slot-class)
+ instance slotd)
+ (let ((slot (find slotd (class-slots class))))
+ (if slot
+ (read-dynamic-slot-value instance (slot-definition-name slotd))
+ (call-next-method))))
+
+(defmethod (setf slot-value-using-class) (new-value (class dynamic-slot-class)
+ instance slotd)
+ (let ((slot (find slotd (class-slots class))))
+ (if slot
+ (write-dynamic-slot-value new-value instance (slot-definition-name slotd))
+ (call-next-method))))
+
+(defmethod slot-boundp-using-class ((class dynamic-slot-class)
+ instance slotd)
+ (let ((slot (find slotd (class-slots class))))
+ (if slot
+ (dynamic-slot-boundp instance (slot-definition-name slotd))
+ (call-next-method))))
+
+(defmethod slot-makunbound-using-class ((class dynamic-slot-class)
+ instance slotd)
+ (let ((slot (find slotd (class-slots class))))
+ (if slot
+ (dynamic-slot-makunbound instance (slot-definition-name slotd))
+ (call-next-method))))
+
+(defclass test-class-1 ()
+ ((slot1 :initarg :slot1)
+ (slot2 :initarg :slot2 :initform nil))
+ (:metaclass dynamic-slot-class))
+
+(defclass test-class-2 (test-class-1)
+ ((slot2 :initarg :slot2 :initform t)
+ (slot3 :initarg :slot3))
+ (:metaclass dynamic-slot-class))
+
+(defvar *one* (make-instance 'test-class-1))
+(defvar *two* (make-instance 'test-class-2 :slot3 1))
+
+(assert (not (slot-boundp *one* 'slot1)))
+(assert (null (slot-value *one* 'slot2)))
+(assert (eq t (slot-value *two* 'slot2)))
+(assert (= 1 (slot-value *two* 'slot3)))
+