~ chicken-core (chicken-5) df10e8ae06e98d27f045463949b8acaef765c6e7

commit df10e8ae06e98d27f045463949b8acaef765c6e7
Author:     Peter Bex <peter.bex@xs4all.nl>
AuthorDate: Sun Sep 29 13:17:58 2013 +0200
Commit:     Christian Kellermann <ckeen@pestilenz.org>
CommitDate: Wed Oct 2 14:26:55 2013 +0200

    Fix read-string! behaviour after peeking at EOF & add regression test.
    
    Slot 6 does not store the peeked character (anymore?), but whether the
    port is in an EOF state.  Peeking goes via ungetc on FILE * ports, and
    via custom logic in other port types.
    
    Signed-off-by: Christian Kellermann <ckeen@pestilenz.org>

diff --git a/extras.scm b/extras.scm
index 613edeef..36b6bc99 100644
--- a/extras.scm
+++ b/extras.scm
@@ -148,9 +148,6 @@
 (define (##sys#read-string! n dest port start)
   (cond ((eq? n 0) 0)
 	(else
-	 (when (##sys#slot port 6)	; peeked?
-	   (##core#inline "C_setsubchar" dest start (##sys#read-char-0 port))
-	   (set! start (fx+ start 1)) )
 	 (let ((rdstring (##sys#slot (##sys#slot port 2) 7)))
            (if rdstring
 	       (let loop ((start start) (n n) (m 0))
diff --git a/tests/port-tests.scm b/tests/port-tests.scm
index bd7c8586..ebba3503 100644
--- a/tests/port-tests.scm
+++ b/tests/port-tests.scm
@@ -300,6 +300,9 @@ EOF
 (test-group "read-string!"
   (let ((in (open-input-string "1234567890"))
         (buf (make-string 5)))
+    (test-equal "peek-char won't influence the result of read-string!"
+                (peek-char in)
+                #\1)
     (test-equal "read-string! won't read past buffer if given #f"
                 (read-string! #f buf in)
                 5)
@@ -317,6 +320,11 @@ EOF
                 3)
     (test-equal "read-string! leaves the buffer's tail intact"
                 buf
+                "89067")
+    (test-equal "after peek-char at EOF, read-string! doesn't mutate the buffer"
+                (begin (peek-char in)
+                       (read-string! #f buf in)
+                       buf)
                 "89067"))
   (let ((in (open-input-string "1234567890"))
         (buf (make-string 5)))
@@ -336,6 +344,12 @@ EOF
                 (read-string! 10 buf in)
                 3)
     (test-equal "read-string! leaves the buffer's tail intact"
+                buf
+                "89067")
+    (test-equal "read-string! at EOF reads nothing"
+                (read-string! 10 buf in)
+                0)
+    (test-equal "read-string! at EOF doesn't mutate the buffer"
                 buf
                 "89067")))