From a05bf0cb7a2baf569618ccdd850d6dfb32f61a6c Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Fri, 5 Mar 2021 21:14:15 +0100
Subject: [PATCH] Fix canonical encoding of Set and Dictionary

---
 implementations/javascript/src/dictionary.ts | 20 +++++++++++++-------
 implementations/javascript/src/encoder.ts    |  8 +-------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/implementations/javascript/src/dictionary.ts b/implementations/javascript/src/dictionary.ts
index d620a93..0352876 100644
--- a/implementations/javascript/src/dictionary.ts
+++ b/implementations/javascript/src/dictionary.ts
@@ -60,10 +60,16 @@ export class Dictionary<V, T extends object = DefaultPointer> extends FlexMap<Va
 
     [PreserveOn](encoder: Encoder<T>) {
         if (encoder.canonical) {
-            const pieces = Array.from(this).map(([k, v]) =>
-                Bytes.concat([canonicalEncode(k), canonicalEncode(v)]));
-            pieces.sort(Bytes.compare);
-            encoder.encoderawvalues(Tag.Dictionary, pieces);
+            const entries = Array.from(this);
+            const pieces = entries.map<[Bytes, number]>(([k, _v], i) => [canonicalEncode(k), i]);
+            pieces.sort((a, b) => Bytes.compare(a[0], b[0]));
+            encoder.emitbyte(Tag.Dictionary);
+            pieces.forEach(([_encodedKey, i]) => {
+                const [k, v] = entries[i];
+                encoder.push(k);
+                encoder.push(v as unknown as Value<T>); // Suuuuuuuper unsound
+            });
+            encoder.emitbyte(Tag.End);
         } else {
             encoder.emitbyte(Tag.Dictionary);
             this.forEach((v, k) => {
@@ -116,9 +122,9 @@ export class Set<T extends object = DefaultPointer> extends FlexSet<Value<T>> {
 
     [PreserveOn](encoder: Encoder<T>) {
         if (encoder.canonical) {
-            const pieces = Array.from(this).map(k => canonicalEncode(k));
-            pieces.sort(Bytes.compare);
-            encoder.encoderawvalues(Tag.Set, pieces);
+            const pieces = Array.from(this).map<[Bytes, Value<T>]>(k => [canonicalEncode(k), k]);
+            pieces.sort((a, b) => Bytes.compare(a[0], b[0]));
+            encoder.encodevalues(Tag.Set, pieces.map(e => e[1]));
         } else {
             encoder.encodevalues(Tag.Set, this);
         }
diff --git a/implementations/javascript/src/encoder.ts b/implementations/javascript/src/encoder.ts
index 5ef4b8e..9647fee 100644
--- a/implementations/javascript/src/encoder.ts
+++ b/implementations/javascript/src/encoder.ts
@@ -1,5 +1,5 @@
 import { Tag } from "./constants";
-import { Bytes, BytesLike, underlying } from "./bytes";
+import { Bytes } from "./bytes";
 import { Value } from "./values";
 import { PreserveOn } from "./symbols";
 import { EncodeError } from "./codec";
@@ -137,12 +137,6 @@ export class Encoder<T extends object> {
         this.emitbyte(Tag.End);
     }
 
-    encoderawvalues(tag: Tag, items: BytesLike[]) {
-        this.emitbyte(tag);
-        items.forEach((i) => this.emitbytes(underlying(i)));
-        this.emitbyte(Tag.End);
-    }
-
     push(v: Encodable<T>) {
         if (isPreservable<never>(v)) {
             v[PreserveOn](this as unknown as Encoder<never>);