1 files changed, 7 insertions(+), 3 deletions(-)

M decode.rkt

@@ 187,7 187,11 @@
 (define (deserialize-bignum _tag data)
   (unless (bytes? data)
     (error "Bignum payload must be bytes"))
-  (integer-bytes->integer data #f #t))
+  (for/fold ([acc 0])
+            ([(chunk idx) (in-indexed data)])
+    (define shift (* 8 (- (sub1 (bytes-length data))
+                          idx)))
+    (bitwise-ior acc (arithmetic-shift chunk shift))))
 
 (define (deserialize-bigneg tag data)
   (- -1 (deserialize-bignum tag data)))


@@ 256,9 260,9 @@
     (check-eqv? (try "1a000f4240") 1000000)
     (check-eqv? (try "1b000000e8d4a51000") 1000000000000)
     (check-eqv? (try "1bffffffffffffffff") 18446744073709551615)
-    ;TODO bignums (check-eqv? (try "c249010000000000000000") 18446744073709551616)
+    (check-eqv? (try "c249010000000000000000") 18446744073709551616)
     (check-eqv? (try "3bffffffffffffffff") -18446744073709551616)
-    ;TODO bignums (check-eqv? (try "c349010000000000000000") -18446744073709551617)
+    (check-eqv? (try "c349010000000000000000") -18446744073709551617)
     (check-eqv? (try "20") -1)
     (check-eqv? (try "29") -10)
     (check-eqv? (try "3863") -100)