js-on-sx: object computed keys + insertion-order tracking

lib/js/runtime.sx

@@ -1293,6 +1293,16 @@
 
 (define js-args (fn (&rest args) args))
 
+(define
+  js-make-list
+  (fn
+    (&rest args)
+    (let
+      ((r (list)))
+      (begin
+        (for-each (fn (x) (append! r x)) args)
+        r))))
+
 (define js-trim (fn (s) (js-trim-left (js-trim-right s))))
 
 (define
@@ -2993,6 +3003,46 @@
 
 (define dict-has? (fn (d k) (contains? (keys d) k)))
 
+(define
+  js-make-obj
+  (fn () (let ((d (dict))) (begin (dict-set! d "__js_order__" (list)) d))))
+
+(define
+  js-obj-order-add!
+  (fn
+    (obj k)
+    (cond
+      ((not (dict? obj)) nil)
+      ((not (contains? (keys obj) "__js_order__")) nil)
+      (else
+        (let
+          ((order (get obj "__js_order__")))
+          (if (contains? order k) nil (append! order k)))))))
+
+(define
+  js-obj-order-remove!
+  (fn
+    (obj k)
+    (cond
+      ((not (dict? obj)) nil)
+      ((not (contains? (keys obj) "__js_order__")) nil)
+      (else
+        (dict-set!
+          obj
+          "__js_order__"
+          (filter (fn (x) (not (= x k))) (get obj "__js_order__")))))))
+
+(define
+  js-obj-set!
+  (fn
+    (obj key val)
+    (let
+      ((sk (js-to-string key)))
+      (begin
+        (if (not (contains? (keys obj) sk)) (js-obj-order-add! obj sk) nil)
+        (dict-set! obj sk val)
+        val))))
+
 (begin
   (define
     js-set-prop
@@ -3001,7 +3051,12 @@
       (cond
         ((js-undefined? obj) (error "js-set-prop: cannot set on undefined"))
         ((= (type-of obj) "dict")
-          (do (dict-set! obj (js-to-string key) val) val))
+          (let
+            ((sk (js-to-string key)))
+            (begin
+              (if (not (contains? (keys obj) sk)) (js-obj-order-add! obj sk) nil)
+              (dict-set! obj sk val)
+              val)))
         ((= (type-of obj) "list") (do (js-list-set! obj key val) val))
         (else val))))
   (define
@@ -3428,16 +3483,35 @@
         (append! acc (char-at s i))
         (js-string-to-list s (+ i 1) acc)))))
 
+(define
+  js-key-internal?
+  (fn
+    (k)
+    (or (= k "__js_order__") (= k "__proto__"))))
+
 (define
   js-object-keys
   (fn
     (o)
     (cond
       ((dict? o)
-        (let
-          ((result (list)))
-          (for-each (fn (k) (append! result k)) (keys o))
-          result))
+        (cond
+          ((contains? (keys o) "__js_order__")
+            (let
+              ((result (list)))
+              (begin
+                (for-each
+                  (fn (k) (if (js-key-internal? k) nil (append! result k)))
+                  (get o "__js_order__"))
+                result)))
+          (else
+            (let
+              ((result (list)))
+              (begin
+                (for-each
+                  (fn (k) (if (js-key-internal? k) nil (append! result k)))
+                  (keys o))
+                result)))))
       (else (list)))))
 
 (define
@@ -3563,9 +3637,85 @@
     (cond
       ((list? o)
         (let ((r (list))) (begin (js-list-keys-loop o 0 r) r)))
-      ((dict? o) (js-object-keys o))
+      ((dict? o) (js-own-property-names-ordered o))
       (else (list)))))
 
+(define
+  js-own-property-names-ordered
+  (fn
+    (o)
+    (let
+      ((all (js-object-keys o))
+        (ints (list))
+        (rest (list)))
+      (begin
+        (for-each
+          (fn
+            (k)
+            (if (js-int-key? k) (append! ints k) (append! rest k)))
+          all)
+        (append (js-sort-int-keys ints) rest)))))
+
+(define
+  js-int-key?
+  (fn
+    (k)
+    (cond
+      ((not (= (type-of k) "string")) false)
+      ((= (len k) 0) false)
+      (else (js-int-key-loop? k 0 (len k))))))
+
+(define
+  js-int-key-loop?
+  (fn
+    (s i n)
+    (cond
+      ((>= i n) true)
+      ((let ((c (char-code-at s i))) (and (>= c 48) (<= c 57)))
+        (js-int-key-loop? s (+ i 1) n))
+      (else false))))
+
+(define
+  js-sort-int-keys
+  (fn
+    (lst)
+    (let
+      ((nums (map js-string-to-number lst)))
+      (begin
+        (js-sort-numbers! nums)
+        (map (fn (n) (str (js-num-to-int n))) nums)))))
+
+(define
+  js-sort-numbers!
+  (fn
+    (lst)
+    (let ((n (len lst)))
+      (js-bubble-sort! lst 0 n))))
+
+(define
+  js-bubble-sort!
+  (fn
+    (lst i n)
+    (cond
+      ((>= i n) nil)
+      (else
+        (begin (js-bubble-sort-inner! lst 0 (- n i 1)) (js-bubble-sort! lst (+ i 1) n))))))
+
+(define
+  js-bubble-sort-inner!
+  (fn
+    (lst j stop)
+    (cond
+      ((>= j stop) nil)
+      ((> (nth lst j) (nth lst (+ j 1)))
+        (let
+          ((a (nth lst j)) (b (nth lst (+ j 1))))
+          (begin
+            (set-nth! lst j b)
+            (set-nth! lst (+ j 1) a)
+            (js-bubble-sort-inner! lst (+ j 1) stop))))
+      (else (js-bubble-sort-inner! lst (+ j 1) stop)))))
+
 (define
   js-object-get-own-property-descriptor
   (fn
@@ -3656,7 +3806,12 @@
     (obj key)
     (cond
       ((dict? obj)
-        (begin (dict-delete! obj (js-to-string key)) true))
+        (let
+          ((sk (js-to-string key)))
+          (begin
+            (js-obj-order-remove! obj sk)
+            (dict-delete! obj sk)
+            true)))
       (else true))))
 
 (define
@@ -4135,14 +4290,17 @@
           (for-each
             (fn
               (k)
-              (let
-                ((val (get v k)))
+              (if
+                (js-key-internal? k)
+                nil
                 (let
-                  ((vs (js-json-stringify-value val)))
-                  (if
-                    (not (js-undefined? vs))
-                    (append! parts (str (js-json-escape-string k) ":" vs))))))
-            (keys v))
+                  ((val (get v k)))
+                  (let
+                    ((vs (js-json-stringify-value val)))
+                    (if
+                      (not (js-undefined? vs))
+                      (append! parts (str (js-json-escape-string k) ":" vs)))))))
+            (js-object-keys v))
           (str "{" (join "," parts) "}")))
       (else "null"))))