Round-trip JSON keys holding a backslash, quote or control character, and generate them in the properties

corpus/round-trip/combinations/escaped-json-keys.json

@@ -0,0 +1,53 @@
+{
+  "content": [
+    {
+      "attrs": {
+        "extensionKey": "toc",
+        "extensionType": "com.atlassian.confluence.macro.core",
+        "parameters": {
+          "back\\slash": 1,
+          "nested\\": {
+            "in\\\"ner": true
+          },
+          "nul\u0000": 2,
+          "say \"hi\"": 3,
+          "tab\tand\u001fus": 4
+        }
+      },
+      "type": "extension"
+    },
+    {
+      "attrs": {
+        "back\\slash": 1,
+        "nul\u0000": 2,
+        "say \"hi\"": 3,
+        "tab\tand\u001fus": 4
+      },
+      "type": "unknownBlock"
+    },
+    {
+      "content": [
+        {
+          "text": "See ",
+          "type": "text"
+        },
+        {
+          "attrs": {
+            "back\\slash": 1,
+            "nul\u0000": 2,
+            "say \"hi\"": 3,
+            "tab\tand\u001fus": 4
+          },
+          "type": "unknownInline"
+        },
+        {
+          "text": " now.",
+          "type": "text"
+        }
+      ],
+      "type": "paragraph"
+    }
+  ],
+  "type": "doc",
+  "version": 1
+}

corpus/round-trip/combinations/escaped-json-keys.md

@@ -0,0 +1,14 @@
+!adf:extension {extensionKey=toc extensionType="com.atlassian.confluence.macro.core" parameters="{\"back\\\\slash\":1,\"nested\\\\\":{\"in\\\\\\\"ner\":true},\"nul\\u0000\":2,\"say \\\"hi\\\"\":3,\"tab\\tand\\u001fus\":4}"}
+
+```adf:unknownBlock
+{
+  "attrs": {
+    "back\\slash": 1,
+    "nul\u0000": 2,
+    "say \"hi\"": 3,
+    "tab\tand\u001fus": 4
+  }
+}
+```
+
+See !adf:carry{json="{\"attrs\":{\"back\\\\slash\":1,\"nul\\u0000\":2,\"say \\\"hi\\\"\":3,\"tab\\tand\\u001fus\":4},\"type\":\"unknownInline\"}"} now.

src/conformance/property-harness.ts

@@ -43,10 +43,7 @@ const numberValue = fc.oneof(
   { arbitrary: fc.constant(-0), weight: 1 },
 )
 
-// V8's JSON.parse returns a wrong key after parsing a key holding an escaped backslash (https://issues.chromium.org/issues/521080746); Bun is unaffected.
-const keyPiece = fc
-  .oneof({ arbitrary: markdownPieces, weight: 4 }, { arbitrary: fc.string({ maxLength: 1, minLength: 1, unit: 'grapheme' }), weight: 1 })
-  .filter((piece) => !/[\\"\x00-\x1f]/.test(piece))
+const keyPiece = fc.oneof({ arbitrary: markdownPieces, weight: 4 }, { arbitrary: fc.string({ maxLength: 1, minLength: 1, unit: 'grapheme' }), weight: 1 })
 export const jsonKey = fc.string({ maxLength: 8, unit: keyPiece })
 
 export const { jsonValue } = fc.letrec<{ jsonValue: JsonValue }>((tie) => ({

todo.md

@@ -24,7 +24,6 @@
 
 | ID | Release | Exempt | Item | R | S | A | G | Goals | Score |
 |---|---|---|---|---|---|---|---|---|---|
-| 64 | 0.2.0 | defect | **Read back unchanged on V8 every JSON key the emitter writes, with a fixture whose key holds `\`, `"` or a control character.** | 4 | 4 | 6 | 8 | 1, 8 | 23.0 |
 | 43 | 0.2.0 | decision | **Give each markdown input its own reader, strict to its own standard.** | 6 | 7 | 8 | 9 | 4, 5 | 20.3 |
 | 65 | 0.2.0 | defect | **Read an image not alone in its paragraph as its alt text linked to its URL, and a titled image alone in its paragraph as the image captioned with its title.** | 5 | 5 | 7 | 7 | 4, 5, 7 | 17.1 |
 | 49 | 0.2.0 |  | **Read a list whose bullet or ordered delimiter changes as two lists, in both readers, and retire `!adf:listBreak`.** | 4 | 5 | 5 | 8 | 4, 5 | 15.5 |
@@ -64,15 +63,6 @@
 
 ## Details
 
-### 64. Read back unchanged on V8 every JSON key the emitter writes, with a fixture whose key holds `\`, `"` or a control character.
-
-`property-harness.ts` strips `\`, `"` and control characters from generated JSON keys, citing V8's
-`JSON.parse` returning a wrong key for an escaped backslash. The library reads `json` attributes
-(`directive-syntax.ts`) and both carries (`opaque-carry.ts`) through that `JSON.parse`, so on Node,
-Deno and Chrome the round-trip would refuse its own output or read back a different key; the fixture
-tells which. Confirm with a fixture first; then read JSON with our own parser or record the gap with
-an ending item. Found by the README-goals audit, 2026-10-03.
-
 ### 43. Give each markdown input its own reader, strict to its own standard.
 
 Today `markdownToAdf` reads CommonMark and the lossless flavour as one input: text shaped like a