~ chicken-core (chicken-5) 04fb8aa6879e8d7d9cea471563bee7f051aba231

commit 04fb8aa6879e8d7d9cea471563bee7f051aba231
Author:     Evan Hanson <evhan@foldling.org>
AuthorDate: Sat Dec 28 19:47:19 2013 +1300
Commit:     Peter Bex <peter.bex@xs4all.nl>
CommitDate: Thu Jan 9 21:12:17 2014 +0100

    Add null guards and fix empty list rewriting in (pair a b) <-> (list ...) type comparisons
    
    This makes sure type comparisons between (pair ...) and (list ...) forms
    don't fall off the end of the list, causing unhelpful errors about
    calling cadr/caddr on null.
    
    Signed-off-by: Peter Bex <peter.bex@xs4all.nl>

diff --git a/scrutinizer.scm b/scrutinizer.scm
index 91a8f69b..0cdd4f23 100644
--- a/scrutinizer.scm
+++ b/scrutinizer.scm
@@ -1158,9 +1158,10 @@
 			 (match1 ct1 t2)
 			 #t)))		; inexact match
 		  ((list)
-		   (and (match1 (second t1) (second t2))
+		   (and (pair? (cdr t2))
+			(match1 (second t1) (second t2))
 			(match1 (third t1)
-				(if (null? (cdr t2))
+				(if (null? (cddr t2))
 				    'null
 				    `(list ,@(cddr t2))))))
 		  (else #f))))
@@ -1173,8 +1174,9 @@
 			 (match1 t1 ct2)
 			 (and (not exact) (not all)))))	; inexact mode: ok
 		  ((list)
-		   (and (match1 (second t1) (second t2))
-			(match1 (if (null? (cdr t1))
+		   (and (pair? (cdr t1))
+			(match1 (second t1) (second t2))
+			(match1 (if (null? (cddr t1))
 				    'null
 				    `(list ,@(cddr t1)))
 				(third t2))))