DISASSEMBLE type-error on bad argument

CLHS specifies `disassemble`'s argument as an *extended function
designator* — i.e. `(or function symbol (cons (eql setf) (cons
symbol null)))` — and mandates a `TYPE-ERROR` otherwise.
`DISASSEMBLE.ERROR.3` iterates the mini-universe expecting
`TYPE-ERROR` for everything outside that set, but ABCL accepted
arbitrary junk, often crashing inside `disassemble-function`.

Added an explicit `typep` guard that signals `TYPE-ERROR` with
`:datum` and `:expected-type` populated. The accepted type is widened
with `(cons (eql lambda) t)` so that `DISASSEMBLE.3`
(`(disassemble '(lambda (x y) (cons y x)))`, which expects success)
keeps passing.

Author: Mark Evenson

src/org/armedbear/lisp/disassemble.lisp

@@ -210,6 +210,14 @@ CL:DISASSEMBLE."
 ;; (get-java-field (elt (#"get" (elt (#"getFields" (#"getClass" #'foo)) 0) #'foo) 0) "value")
 
 (defun disassemble (arg)
+  (unless (typep arg '(or function symbol
+                       (cons (eql setf) (cons symbol null))
+                       (cons (eql lambda) t)))
+    (error 'type-error
+           :datum arg
+           :expected-type '(or function symbol
+                            (cons (eql setf) (cons symbol null))
+                            (cons (eql lambda) t))))
   (print-lines-with-prefix (disassemble-function arg)))
 
 (defun print-lines-with-prefix (string)