bits.scm

(test-group "records"
            ;; Define a record type with setters for each field
            (define-record test (setter bit) (setter byte) (setter nibble) (setter bytes))
            ;; Define a 'bits' conversion function
            (define test-bits
              (make-bits
               (bit test-bit)         ;  1 bit
               (byte test-byte)       ;  8 bits
               (nibble test-nibble)   ;  4 bits
               (bytes 2 test-bytes))) ; 16 bits
            ;; Define a blob to read/write from
            (define test-blob (make-blob 4)) ; 32 bits

            (let loop ((count 0))
              (define bit (= 1 (random 2)))
              (define nibble (random 16))
              (define byte (random 256))
              (define byte-high (random 256))
              (define byte-low (random 256))
              (define test-thing (make-test bit byte nibble (u8vector->blob (list->u8vector (list byte-high byte-low)))))
              
              (test (format "Write record ~S" count) 29 
                    (test-bits test-thing #f test-blob 0))
              (test (format "Read record ~S" count)  29 
                    (test-bits test-thing #t test-blob 0))
              (test (format "Correct test-bit ~S" count) bit
                    (test-bit test-thing))
              (test (format "Correct test-byte ~S" count) byte
                    (test-byte test-thing))
              (test (format "Correct test-nibble ~S" count) nibble
                    (test-nibble test-thing))
              (test (format "Correct test-bytes (high) ~S" count) byte-high
                    (u8vector-ref (blob->u8vector/shared (test-bytes test-thing)) 0))
              (test (format "Correct test-bytes (low) ~S" count) byte-low
                    (u8vector-ref (blob->u8vector/shared (test-bytes test-thing)) 1))
              (when (> 16 count)
                    (loop (+ count 1)))))