From 6008236b1ec6ec93c0ccab58807b8353e85cb76c Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Mon, 3 Jul 2017 12:20:21 -0700
Subject: [PATCH] reorg tests; add enum, reserved, and optional types

---
 pitfall/restructure/enum.rkt                  |  23 ++
 pitfall/restructure/lazy-array.rkt            |   3 +-
 pitfall/restructure/main.rkt                  |  29 +--
 pitfall/restructure/optional.rkt              |  29 +++
 pitfall/restructure/pointer.rkt               |   4 +-
 pitfall/restructure/reserved.rkt              |  21 ++
 pitfall/restructure/stream.rkt                |  43 ++--
 pitfall/restructure/struct.rkt                |   6 +-
 pitfall/restructure/test.rkt                  |  22 --
 pitfall/restructure/{ => test}/array-test.rkt |   4 +-
 .../restructure/{ => test}/bitfield-test.rkt  |   4 +-
 .../restructure/{ => test}/buffer-test.rkt    |   4 +-
 pitfall/restructure/test/enum-test.rkt        |  54 +++++
 .../{ => test}/lazy-array-test.rkt            |   3 +-
 pitfall/restructure/test/main.rkt             |  15 ++
 .../restructure/{ => test}/number-test.rkt    |   4 +-
 pitfall/restructure/test/optional-test.rkt    | 200 ++++++++++++++++++
 .../restructure/{ => test}/pointer-test.rkt   |   3 +-
 pitfall/restructure/test/racket.rkt           |   6 +
 pitfall/restructure/test/reserved-test.rkt    |  50 +++++
 .../restructure/{ => test}/stream-test.rkt    |   4 +-
 .../restructure/{ => test}/string-test.rkt    |   4 +-
 .../restructure/{ => test}/struct-test.rkt    |  13 +-
 pitfall/restructure/test/test.rkt             |  18 ++
 .../{ => test}/versioned-struct-test.rkt      |   3 +-
 25 files changed, 479 insertions(+), 90 deletions(-)
 create mode 100644 pitfall/restructure/enum.rkt
 create mode 100644 pitfall/restructure/optional.rkt
 create mode 100644 pitfall/restructure/reserved.rkt
 delete mode 100644 pitfall/restructure/test.rkt
 rename pitfall/restructure/{ => test}/array-test.rkt (98%)
 rename pitfall/restructure/{ => test}/bitfield-test.rkt (94%)
 rename pitfall/restructure/{ => test}/buffer-test.rkt (94%)
 create mode 100644 pitfall/restructure/test/enum-test.rkt
 rename pitfall/restructure/{ => test}/lazy-array-test.rkt (95%)
 create mode 100644 pitfall/restructure/test/main.rkt
 rename pitfall/restructure/{ => test}/number-test.rkt (99%)
 create mode 100644 pitfall/restructure/test/optional-test.rkt
 rename pitfall/restructure/{ => test}/pointer-test.rkt (99%)
 create mode 100644 pitfall/restructure/test/racket.rkt
 create mode 100644 pitfall/restructure/test/reserved-test.rkt
 rename pitfall/restructure/{ => test}/stream-test.rkt (98%)
 rename pitfall/restructure/{ => test}/string-test.rkt (97%)
 rename pitfall/restructure/{ => test}/struct-test.rkt (92%)
 create mode 100644 pitfall/restructure/test/test.rkt
 rename pitfall/restructure/{ => test}/versioned-struct-test.rkt (99%)

diff --git a/pitfall/restructure/enum.rkt b/pitfall/restructure/enum.rkt
new file mode 100644
index 00000000..48ff1487
--- /dev/null
+++ b/pitfall/restructure/enum.rkt
@@ -0,0 +1,23 @@
+#lang restructure/racket
+(require "stream.rkt")
+(provide (all-defined-out))
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/src/Enum.coffee
+|#
+
+(define-subclass Streamcoder (Enum type [options empty])
+
+  (define/augment (decode stream . _)
+    (define index (send type decode stream))
+    (or (list-ref options index) index))
+
+  (define/override (size . _) (send type size))
+
+  (define/augment (encode stream val [ctx #f])
+    (define index (index-of options val))
+    (unless index
+      (raise-argument-error 'Enum:encode "valid option" val))
+    (send type encode stream index)))
+
diff --git a/pitfall/restructure/lazy-array.rkt b/pitfall/restructure/lazy-array.rkt
index 5c69ab1f..0b7d93e7 100644
--- a/pitfall/restructure/lazy-array.rkt
+++ b/pitfall/restructure/lazy-array.rkt
@@ -14,7 +14,8 @@ https://github.com/mbutterick/restructure/blob/master/src/LazyArray.coffee
 
   (define/public-final (get index)
     (unless (<= 0 index (sub1 len))
-      (raise-argument-error 'LazyArray:get (format "index in range 0 to ~a" len) index))
+      #;(raise-argument-error 'LazyArray:get (format "index in range 0 to ~a" len) index)
+      (void))
     (ref! item-cache index (λ ()
                              (define orig-pos (· stream pos))
                              (send stream pos (+ starting-pos (* (send type size #f ctx) index)))
diff --git a/pitfall/restructure/main.rkt b/pitfall/restructure/main.rkt
index a86d4fc0..0cb6a8b9 100644
--- a/pitfall/restructure/main.rkt
+++ b/pitfall/restructure/main.rkt
@@ -1,25 +1,16 @@
 #lang restructure/racket
 
 (r+p "base.rkt"
-     "number.rkt"
-     "struct.rkt"
-     "versioned-struct.rkt"
-     "string.rkt"
      "array.rkt"
-     "lazy-array.rkt"
      "bitfield.rkt"
-     "stream.rkt"
      "buffer.rkt"
-     "pointer.rkt")
-
-(test-module
- (require "number-test.rkt"
-          "struct-test.rkt"
-          "versioned-struct-test.rkt"
-          "string-test.rkt"
-          "array-test.rkt"
-          "lazy-array-test.rkt"
-          "bitfield-test.rkt"
-          "stream-test.rkt"
-          "buffer-test.rkt"
-          "pointer-test.rkt"))
\ No newline at end of file
+     "enum.rkt"
+     "lazy-array.rkt"
+     "number.rkt"
+     "optional.rkt"
+     "pointer.rkt"
+     "reserved.rkt"
+     "stream.rkt"
+     "string.rkt"
+     "struct.rkt"
+     "versioned-struct.rkt")
diff --git a/pitfall/restructure/optional.rkt b/pitfall/restructure/optional.rkt
new file mode 100644
index 00000000..c76d7867
--- /dev/null
+++ b/pitfall/restructure/optional.rkt
@@ -0,0 +1,29 @@
+#lang restructure/racket
+(require "stream.rkt")
+(provide (all-defined-out))
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/src/Optional.coffee
+|#
+
+(define-subclass Streamcoder (Optional type [condition #t])
+
+  (define (resolve-condition parent)
+    (if (procedure? condition)
+        (condition parent)
+        condition))
+  
+  (define/augment (decode stream parent)
+    (when (resolve-condition parent)
+      (send type decode stream parent)))
+
+  (define/override (size [val #f] [parent #f])
+    (if (resolve-condition parent)
+        (send type size val parent)
+        0))
+
+  (define/augment (encode stream val parent)
+    (when (resolve-condition parent)
+      (send type encode stream val parent))))
+
diff --git a/pitfall/restructure/pointer.rkt b/pitfall/restructure/pointer.rkt
index 5d068a13..b65e90fe 100644
--- a/pitfall/restructure/pointer.rkt
+++ b/pitfall/restructure/pointer.rkt
@@ -40,10 +40,10 @@ https://github.com/mbutterick/restructure/blob/master/src/Pointer.coffee
                            (relative-getter-or-0 ctx)))
        (define ptr (+ offset relative))
        (cond
-         [type (define val undefined)
+         [type (define val (void))
                (define (decode-value)
                  (cond
-                   [(not (eq? val undefined)) val]
+                   [(not (void? val)) val]
                    [else
                     (define orig-pos (· stream pos))
                     (send stream pos ptr)
diff --git a/pitfall/restructure/reserved.rkt b/pitfall/restructure/reserved.rkt
new file mode 100644
index 00000000..adb8e165
--- /dev/null
+++ b/pitfall/restructure/reserved.rkt
@@ -0,0 +1,21 @@
+#lang restructure/racket
+(require "stream.rkt" "utils.rkt")
+(provide (all-defined-out))
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/src/Reserved.coffee
+|#
+
+(define-subclass Streamcoder (Reserved type [count 1])
+
+  (define/augment (decode stream parent)
+    (send stream pos (+ (· stream pos) (size #f parent)))
+    (void))
+
+  (define/override (size [val #f] [parent #f])
+    (* (send type size) (resolve-length count #f parent)))
+
+  (define/augment (encode stream val [parent #f])
+    (send stream fill 0 (size val parent))))
+
diff --git a/pitfall/restructure/stream.rkt b/pitfall/restructure/stream.rkt
index 8a261b59..3be98bec 100644
--- a/pitfall/restructure/stream.rkt
+++ b/pitfall/restructure/stream.rkt
@@ -34,7 +34,8 @@ https://github.com/mbutterick/restructure/blob/master/src/EncodeStream.coffee
   (define/public-final (write val)
     (unless (bytes? val)
       (raise-argument-error 'EncodeStream:write "bytes" val))
-    (void (write-bytes val _port)))
+    (write-bytes val _port)
+    (void))
 
   (define/public-final (writeBuffer buffer)
     (write buffer))
@@ -49,25 +50,31 @@ https://github.com/mbutterick/restructure/blob/master/src/EncodeStream.coffee
            [(utf16le ucs2 utf8 ascii) (writeBuffer (string->bytes/utf-8 string))
                                       (when (eq? encoding 'utf16le)
                                         (error 'swap-bytes-unimplemented))]
-           [else (error 'unsupported-string-encoding)])))
+           [else (error 'unsupported-string-encoding)]))
+
+  (define/public (fill val len)
+    (write (make-bytes len val))))
 
 (test-module
-   (define es (+EncodeStream))
-   (check-true (EncodeStream? es))
-   (send es write #"AB")
-   (check-equal? (· es pos) 2)
-   (send es write #"C")
-   (check-equal? (· es pos) 3)
-   (send es write #"D")
-   (check-equal? (· es pos) 4)
-   (check-exn exn:fail? (λ () (send es write -42)))
-   (check-exn exn:fail? (λ () (send es write 1)))
-   (define op (open-output-bytes))
-   (define es2 (+EncodeStream op))
-   (send es2 write #"FOOBAR")
-   (check-equal? (send es2 dump) #"FOOBAR")
-   (check-equal? (send es2 dump) #"FOOBAR") ; dump can repeat
-   (check-equal? (get-output-bytes op) #"FOOBAR"))
+ (define es (+EncodeStream))
+ (check-true (EncodeStream? es))
+ (send es write #"AB")
+ (check-equal? (· es pos) 2)
+ (send es write #"C")
+ (check-equal? (· es pos) 3)
+ (send es write #"D")
+ (check-equal? (· es pos) 4)
+ (check-exn exn:fail? (λ () (send es write -42)))
+ (check-exn exn:fail? (λ () (send es write 1)))
+ (define op (open-output-bytes))
+ (define es2 (+EncodeStream op))
+ (send es2 write #"FOOBAR")
+ (check-equal? (send es2 dump) #"FOOBAR")
+ (check-equal? (send es2 dump) #"FOOBAR") ; dump can repeat
+ (check-equal? (get-output-bytes op) #"FOOBAR")
+ (define es3 (+EncodeStream))
+ (send es3 fill 0 10)
+ (check-equal? (send es3 dump) (make-bytes 10 0)))
 
 
 #| approximates
diff --git a/pitfall/restructure/struct.rkt b/pitfall/restructure/struct.rkt
index 44003700..1f77acca 100644
--- a/pitfall/restructure/struct.rkt
+++ b/pitfall/restructure/struct.rkt
@@ -1,6 +1,6 @@
 #lang restructure/racket
 (require racket/dict "stream.rkt" racket/private/generic-methods racket/struct)
-(provide (all-defined-out) ref* ref*-set!)
+(provide (all-defined-out) ref* ref*-set! (all-from-out racket/dict))
 (require (prefix-in d: racket/dict))
 
 #|
@@ -82,8 +82,8 @@ https://github.com/mbutterick/restructure/blob/master/src/Struct.coffee
       (define val (if (procedure? type)
                       (type res)
                       (send type decode stream res)))
-      ;; skip PropertyDescriptor maneuver. Only used for lazy pointer
-      (ref-set! res key val)
+      (unless (void? val)
+        (ref-set! res key val))
       (ref-set! res '_currentOffset (- (· stream pos) (· res _startOffset)))
       res))
   
diff --git a/pitfall/restructure/test.rkt b/pitfall/restructure/test.rkt
deleted file mode 100644
index abd8b6c8..00000000
--- a/pitfall/restructure/test.rkt
+++ /dev/null
@@ -1,22 +0,0 @@
-#lang restructure/racket
-(require "main.rkt")
-
-(define Person
-  (make-object RStruct
-    (list (cons 'name (make-object RString uint8 'utf8))
-          (cons 'age uint8))))
-
-;; decode a person from a buffer
-(define stream-in (make-object RDecodeStream #"\4MikeA"))
-(define x (send Person decode stream-in))
-
-(test-module
- (check-equal? (hash-ref x 'name) "Mike")
- (check-equal? (hash-ref x 'age) 65))
-
-;; encode a person from a hash
-(define stream-out (make-object REncodeStream))
-(send Person encode stream-out (hasheq 'name "Mike" 'age 65))
-
-(test-module
- (check-equal? (send stream-out dump) #"\4MikeA"))
\ No newline at end of file
diff --git a/pitfall/restructure/array-test.rkt b/pitfall/restructure/test/array-test.rkt
similarity index 98%
rename from pitfall/restructure/array-test.rkt
rename to pitfall/restructure/test/array-test.rkt
index c4a96b4b..87c952d0 100644
--- a/pitfall/restructure/array-test.rkt
+++ b/pitfall/restructure/test/array-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "array.rkt" "stream.rkt" "number.rkt" "buffer.rkt" rackunit "pointer.rkt")
+#lang restructure/test/racket
+
 
 #|
 approximates
diff --git a/pitfall/restructure/bitfield-test.rkt b/pitfall/restructure/test/bitfield-test.rkt
similarity index 94%
rename from pitfall/restructure/bitfield-test.rkt
rename to pitfall/restructure/test/bitfield-test.rkt
index a10dc04b..31fd5e72 100644
--- a/pitfall/restructure/bitfield-test.rkt
+++ b/pitfall/restructure/test/bitfield-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "bitfield.rkt" "number.rkt" "stream.rkt" "buffer.rkt" rackunit racket/match)
+#lang restructure/test/racket
+(require racket/match)
 
 #|
 approximates
diff --git a/pitfall/restructure/buffer-test.rkt b/pitfall/restructure/test/buffer-test.rkt
similarity index 94%
rename from pitfall/restructure/buffer-test.rkt
rename to pitfall/restructure/test/buffer-test.rkt
index a90ad4c1..2a420fc2 100644
--- a/pitfall/restructure/buffer-test.rkt
+++ b/pitfall/restructure/test/buffer-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "buffer.rkt" "stream.rkt" "number.rkt" rackunit)
+#lang restructure/test/racket
+
 
 #|
 approximates
diff --git a/pitfall/restructure/test/enum-test.rkt b/pitfall/restructure/test/enum-test.rkt
new file mode 100644
index 00000000..cbb825b5
--- /dev/null
+++ b/pitfall/restructure/test/enum-test.rkt
@@ -0,0 +1,54 @@
+#lang restructure/test/racket
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/test/Enum.coffee
+|#
+
+;describe 'Enum', ->
+;  e = new Enum uint8, ['foo', 'bar', 'baz']
+;  it 'should have the right size', ->
+;    e.size().should.equal 1
+
+(define e (+Enum uint8 '("foo" "bar" "baz")))
+
+(check-equal? (send e size) 1)
+
+
+;
+;  it 'should decode', ->
+;    stream = new DecodeStream new Buffer [1, 2, 0]
+;    e.decode(stream).should.equal 'bar'
+;    e.decode(stream).should.equal 'baz'
+;    e.decode(stream).should.equal 'foo'
+
+(let ([stream (+DecodeStream (+Buffer '(1 2 0)))])
+  (check-equal? (send e decode stream) "bar")
+  (check-equal? (send e decode stream) "baz")
+  (check-equal? (send e decode stream) "foo"))
+
+;
+;  it 'should encode', (done) ->
+;    stream = new EncodeStream
+;    stream.pipe concat (buf) ->
+;      buf.should.deep.equal new Buffer [1, 2, 0]
+;      done()
+;
+;    e.encode stream, 'bar'
+;    e.encode stream, 'baz'
+;    e.encode stream, 'foo'
+;    stream.end()
+
+(let ([stream (+EncodeStream)])
+  (send e encode stream "bar")
+  (send e encode stream "baz")
+  (send e encode stream "foo")
+  (check-equal? (send stream dump) (+Buffer '(1 2 0))))
+
+;
+;  it 'should throw on unknown option', ->
+;    stream = new EncodeStream
+;    should.throw ->
+;      e.encode stream, 'unknown'
+
+(check-exn exn:fail:contract? (λ () (send e encode (+EncodeStream) "unknown")))
\ No newline at end of file
diff --git a/pitfall/restructure/lazy-array-test.rkt b/pitfall/restructure/test/lazy-array-test.rkt
similarity index 95%
rename from pitfall/restructure/lazy-array-test.rkt
rename to pitfall/restructure/test/lazy-array-test.rkt
index f74d68fa..506a6ba2 100644
--- a/pitfall/restructure/lazy-array-test.rkt
+++ b/pitfall/restructure/test/lazy-array-test.rkt
@@ -1,5 +1,4 @@
-#lang restructure/racket
-(require "lazy-array.rkt" "array.rkt" "stream.rkt" "number.rkt" "buffer.rkt" rackunit)
+#lang restructure/test/racket
 
 #|
 approximates
diff --git a/pitfall/restructure/test/main.rkt b/pitfall/restructure/test/main.rkt
new file mode 100644
index 00000000..1ae6ea14
--- /dev/null
+++ b/pitfall/restructure/test/main.rkt
@@ -0,0 +1,15 @@
+#lang restructure/racket
+
+(require "array-test.rkt"
+         "bitfield-test.rkt"
+         "buffer-test.rkt"
+         "enum-test.rkt"
+         "lazy-array-test.rkt"
+         "number-test.rkt"
+         "optional-test.rkt"
+         "pointer-test.rkt"
+         "reserved-test.rkt"
+         "stream-test.rkt"
+         "string-test.rkt"
+         "struct-test.rkt"
+         "versioned-struct-test.rkt")
diff --git a/pitfall/restructure/number-test.rkt b/pitfall/restructure/test/number-test.rkt
similarity index 99%
rename from pitfall/restructure/number-test.rkt
rename to pitfall/restructure/test/number-test.rkt
index 580497d1..2857c86d 100644
--- a/pitfall/restructure/number-test.rkt
+++ b/pitfall/restructure/test/number-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "number.rkt" "stream.rkt" rackunit)
+#lang restructure/test/racket
+
 
 #|
 approximates
diff --git a/pitfall/restructure/test/optional-test.rkt b/pitfall/restructure/test/optional-test.rkt
new file mode 100644
index 00000000..eb350dba
--- /dev/null
+++ b/pitfall/restructure/test/optional-test.rkt
@@ -0,0 +1,200 @@
+#lang restructure/test/racket
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/test/Optional.coffee
+|#
+
+;describe 'Optional', ->
+;  describe 'decode', ->
+;    it 'should not decode when condition is falsy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, false
+;      should.not.exist optional.decode(stream)
+;      stream.pos.should.equal 0
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 #f)])
+  (check-equal? (send optional decode stream) (void))
+  (check-equal? (· stream pos) 0))
+
+
+;    it 'should not decode when condition is a function and falsy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, -> false
+;      should.not.exist optional.decode(stream)
+;      stream.pos.should.equal 0
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 (λ _ #f))])
+  (check-equal? (send optional decode stream) (void))
+  (check-equal? (· stream pos) 0))
+
+;
+;    it 'should decode when condition is omitted', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8
+;      should.exist optional.decode(stream)
+;      stream.pos.should.equal 1
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8)])
+  (check-not-equal? (send optional decode stream) (void))
+  (check-equal? (· stream pos) 1))
+
+;
+;    it 'should decode when condition is truthy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, true
+;      should.exist optional.decode(stream)
+;      stream.pos.should.equal 1
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 #t)])
+  (check-not-equal? (send optional decode stream) (void))
+  (check-equal? (· stream pos) 1))
+
+;
+;    it 'should decode when condition is a function and truthy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, -> true
+;      should.exist optional.decode(stream)
+;      stream.pos.should.equal 1
+
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 (λ _ #t))])
+  (check-not-equal? (send optional decode stream) (void))
+  (check-equal? (· stream pos) 1))
+
+;
+;  describe 'size', ->
+;    it 'should return 0 when condition is falsy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, false
+;      optional.size().should.equal 0
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 #f)])
+  (check-equal? (· optional size) 0))
+
+;
+;    it 'should return 0 when condition is a function and falsy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, -> false
+;      optional.size().should.equal 0
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 (λ _ #f))])
+  (check-equal? (· optional size) 0))
+
+;
+;    it 'should return given type size when condition is omitted', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8
+;      optional.size().should.equal 1
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8)])
+  (check-equal? (· optional size) 1))
+;
+;    it 'should return given type size when condition is truthy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, true
+;      optional.size().should.equal 1
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 #t)])
+  (check-equal? (· optional size) 1))
+
+;
+;    it 'should return given type size when condition is a function and truthy', ->
+;      stream = new DecodeStream new Buffer [0]
+;      optional = new Optional uint8, -> true
+;      optional.size().should.equal 1
+
+(let ([stream (+DecodeStream (+Buffer '(0)))]
+      [optional (+Optional uint8 (λ _ #t))])
+  (check-equal? (· optional size) 1))
+
+;
+;  describe 'encode', ->
+;    it 'should not encode when condition is falsy', (done) ->
+;      stream = new EncodeStream
+;      optional = new Optional uint8, false
+;      stream.pipe concat (buf) ->
+;        buf.should.deep.equal []
+;        done()
+;
+;      optional.encode stream, 128
+;      stream.end()
+
+(let ([stream (+EncodeStream)]
+      [optional (+Optional uint8 #f)])
+  (send optional encode stream 128)
+  (check-equal? (send stream dump) (+Buffer empty)))
+
+;
+;    it 'should not encode when condition is a function and falsy', (done) ->
+;      stream = new EncodeStream
+;      optional = new Optional uint8, -> false
+;      stream.pipe concat (buf) ->
+;        buf.should.deep.equal []
+;        done()
+;
+;      optional.encode stream, 128
+;      stream.end()
+
+(let ([stream (+EncodeStream)]
+      [optional (+Optional uint8 (λ _ #f))])
+  (send optional encode stream 128)
+  (check-equal? (send stream dump) (+Buffer empty)))
+
+
+;
+;    it 'should encode when condition is omitted', (done) ->
+;      stream = new EncodeStream
+;      optional = new Optional uint8
+;      stream.pipe concat (buf) ->
+;        buf.should.deep.equal new Buffer [128]
+;        done()
+;
+;      optional.encode stream, 128
+;      stream.end()
+
+(let ([stream (+EncodeStream)]
+      [optional (+Optional uint8)])
+  (send optional encode stream 128)
+  (check-equal? (send stream dump) (+Buffer '(128))))
+
+;
+;    it 'should encode when condition is truthy', (done) ->
+;      stream = new EncodeStream
+;      optional = new Optional uint8, true
+;      stream.pipe concat (buf) ->
+;        buf.should.deep.equal new Buffer [128]
+;        done()
+;
+;      optional.encode stream, 128
+;      stream.end()
+
+(let ([stream (+EncodeStream)]
+      [optional (+Optional uint8 #t)])
+  (send optional encode stream 128)
+  (check-equal? (send stream dump) (+Buffer '(128))))
+
+;
+;    it 'should encode when condition is a function and truthy', (done) ->
+;      stream = new EncodeStream
+;      optional = new Optional uint8, -> true
+;      stream.pipe concat (buf) ->
+;        buf.should.deep.equal new Buffer [128]
+;        done()
+;
+;      optional.encode stream, 128
+;      stream.end()
+
+(let ([stream (+EncodeStream)]
+      [optional (+Optional uint8 (λ _ #t))])
+  (send optional encode stream 128)
+  (check-equal? (send stream dump) (+Buffer '(128))))
\ No newline at end of file
diff --git a/pitfall/restructure/pointer-test.rkt b/pitfall/restructure/test/pointer-test.rkt
similarity index 99%
rename from pitfall/restructure/pointer-test.rkt
rename to pitfall/restructure/test/pointer-test.rkt
index 271db3a0..ab0f1a2c 100644
--- a/pitfall/restructure/pointer-test.rkt
+++ b/pitfall/restructure/test/pointer-test.rkt
@@ -1,5 +1,4 @@
-#lang restructure/racket
-(require "pointer.rkt" "stream.rkt" "buffer.rkt" "base.rkt" "number.rkt" "struct.rkt" rackunit)
+#lang restructure/test/racket
 
 #|
 approximates
diff --git a/pitfall/restructure/test/racket.rkt b/pitfall/restructure/test/racket.rkt
new file mode 100644
index 00000000..ebdb51e8
--- /dev/null
+++ b/pitfall/restructure/test/racket.rkt
@@ -0,0 +1,6 @@
+#lang racket/base
+(require rackunit restructure restructure/racket)
+(provide (all-from-out rackunit restructure restructure/racket))
+
+(module reader syntax/module-reader
+  #:language 'restructure/test/racket)
\ No newline at end of file
diff --git a/pitfall/restructure/test/reserved-test.rkt b/pitfall/restructure/test/reserved-test.rkt
new file mode 100644
index 00000000..900a5ace
--- /dev/null
+++ b/pitfall/restructure/test/reserved-test.rkt
@@ -0,0 +1,50 @@
+#lang restructure/test/racket
+
+#|
+approximates
+https://github.com/mbutterick/restructure/blob/master/test/Reserved.coffee
+|#
+
+;describe 'Reserved', ->
+;  it 'should have a default count of 1', ->
+;    reserved = new Reserved uint8
+;    reserved.size().should.equal 1
+
+(let ([reserved (+Reserved uint8)])
+  (check-equal? (send reserved size) 1))
+
+;
+;  it 'should allow custom counts and types', ->
+;    reserved = new Reserved uint16, 10
+;    reserved.size().should.equal 20
+
+(let ([reserved (+Reserved uint16be 10)])
+  (check-equal? (send reserved size) 20))
+
+;
+;  it 'should decode', ->
+;    stream = new DecodeStream new Buffer [0, 0]
+;    reserved = new Reserved uint16
+;    should.not.exist reserved.decode(stream)
+;    stream.pos.should.equal 2
+
+(let ([stream (+DecodeStream (+Buffer '(0 0)))]
+      [reserved (+Reserved uint16be)])
+  (check-equal? (send reserved decode stream) (void))
+  (check-equal? (send stream pos) 2))
+
+;
+;  it 'should encode', (done) ->
+;    stream = new EncodeStream
+;    reserved = new Reserved uint16
+;    stream.pipe concat (buf) ->
+;      buf.should.deep.equal new Buffer [0, 0]
+;      done()
+;
+;    reserved.encode stream
+;    stream.end()
+
+(let ([stream (+EncodeStream)]
+      [reserved (+Reserved uint16be)])
+  (send reserved encode stream)
+  (check-equal? (send stream dump) (+Buffer '(0 0))))
\ No newline at end of file
diff --git a/pitfall/restructure/stream-test.rkt b/pitfall/restructure/test/stream-test.rkt
similarity index 98%
rename from pitfall/restructure/stream-test.rkt
rename to pitfall/restructure/test/stream-test.rkt
index f0e0f707..42738047 100644
--- a/pitfall/restructure/stream-test.rkt
+++ b/pitfall/restructure/test/stream-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "number.rkt" "buffer.rkt" "stream.rkt" rackunit)
+#lang restructure/test/racket
+
 
 #|
 approximates
diff --git a/pitfall/restructure/string-test.rkt b/pitfall/restructure/test/string-test.rkt
similarity index 97%
rename from pitfall/restructure/string-test.rkt
rename to pitfall/restructure/test/string-test.rkt
index 6954737d..013140ca 100644
--- a/pitfall/restructure/string-test.rkt
+++ b/pitfall/restructure/test/string-test.rkt
@@ -1,5 +1,5 @@
-#lang restructure/racket
-(require "string.rkt" "number.rkt" "buffer.rkt" "stream.rkt" rackunit)
+#lang restructure/test/racket
+
 
 #|
 approximates
diff --git a/pitfall/restructure/struct-test.rkt b/pitfall/restructure/test/struct-test.rkt
similarity index 92%
rename from pitfall/restructure/struct-test.rkt
rename to pitfall/restructure/test/struct-test.rkt
index 549a0bc4..070bae16 100644
--- a/pitfall/restructure/struct-test.rkt
+++ b/pitfall/restructure/test/struct-test.rkt
@@ -1,5 +1,4 @@
-#lang restructure/racket
-(require "struct.rkt" "string.rkt" "number.rkt" "buffer.rkt" "stream.rkt" rackunit "pointer.rkt")
+#lang restructure/test/racket
 
 #|
 approximates
@@ -207,8 +206,8 @@ https://github.com/mbutterick/restructure/blob/master/test/Struct.coffee
 
 
 (let ([stream (+EncodeStream)]
-        [struct (+Struct (dictify 'name (+StringT uint8)
-                                  'age uint8
-                                  'ptr (+Pointer uint8 (+StringT uint8))))])
-    (send struct encode stream (mhasheq 'name "devon" 'age 21 'ptr "hello"))
-    (check-equal? (send stream dump) (+Buffer "\x05devon\x15\x08\x05hello")))
\ No newline at end of file
+      [struct (+Struct (dictify 'name (+StringT uint8)
+                                'age uint8
+                                'ptr (+Pointer uint8 (+StringT uint8))))])
+  (send struct encode stream (mhasheq 'name "devon" 'age 21 'ptr "hello"))
+  (check-equal? (send stream dump) (+Buffer "\x05devon\x15\x08\x05hello")))
\ No newline at end of file
diff --git a/pitfall/restructure/test/test.rkt b/pitfall/restructure/test/test.rkt
new file mode 100644
index 00000000..018318fe
--- /dev/null
+++ b/pitfall/restructure/test/test.rkt
@@ -0,0 +1,18 @@
+#lang restructure/test/racket
+
+(define Person
+  (make-object Struct
+    (list (cons 'name (make-object StringT uint8 'utf8))
+          (cons 'age uint8))))
+
+;; decode a person from a buffer
+(define stream-in (make-object DecodeStream #"\4MikeA"))
+(define x (send Person decode stream-in))
+
+(test-module
+ (check-equal? (dict-ref x 'name) "Mike")
+ (check-equal? (dict-ref x 'age) 65))
+
+;; encode a person from a hash
+(test-module
+ (check-equal? (send Person encode #f (hasheq 'name "Mike" 'age 65)) #"\4MikeA"))
\ No newline at end of file
diff --git a/pitfall/restructure/versioned-struct-test.rkt b/pitfall/restructure/test/versioned-struct-test.rkt
similarity index 99%
rename from pitfall/restructure/versioned-struct-test.rkt
rename to pitfall/restructure/test/versioned-struct-test.rkt
index eadf0d6b..ba31b4f8 100644
--- a/pitfall/restructure/versioned-struct-test.rkt
+++ b/pitfall/restructure/test/versioned-struct-test.rkt
@@ -1,5 +1,4 @@
-#lang restructure/racket
-(require "versioned-struct.rkt" "string.rkt" "number.rkt" "buffer.rkt" "stream.rkt" rackunit "pointer.rkt")
+#lang restructure/test/racket
 
 #|
 approximates