Write an unnamed opcode in ASM as its raw byte, 0xba

README.md

@@ -171,7 +171,8 @@ under the rules before Chronicle as well as after it.
 - **ASM cannot hold every script.** It does not record how data was pushed, so
   `--asm -o` refuses a result with a non-minimal push (optimized code is
   minimal, but `OP_0 OP_IF` blocks and data after `OP_RETURN` are kept
-  verbatim), a truncated push, an unnamed opcode, or only data pushes, rather
+  verbatim), a truncated push, an unnamed opcode with `@smartledger/bsv` older
+  than 9.11.1, or only data pushes, rather
   than write a different script.
   Hex and `--binary` output are always exact.
 - **Signatures commit to the script.** `OP_CHECKSIG` signs the script code, so

package.json

@@ -44,6 +44,6 @@
     "@smartledger/bsv": "^9.10.1"
   },
   "devDependencies": {
-    "@smartledger/bsv": "^9.11.0"
+    "@smartledger/bsv": "^9.11.1"
   }
 }

src/script.js

@@ -181,6 +181,9 @@ function toAsm (ops, { maxData = 0, bare = false } = {}) {
       const shown = maxData && hex.length > maxData * 2 ? hex.slice(0, maxData * 2) + '…' : hex
       return op.code >= OP.OP_PUSHDATA1 && !bare ? `${opName(op.code)}:${shown}` : shown
     }
+    // An opcode with no name is written as its raw byte, as @smartledger/bsv
+    // writes it (and reads it back from 9.11.1).
+    if (bare && !NAMES[op.code]) return '0x' + op.code.toString(16).padStart(2, '0')
     return opName(op.code)
   }).join(' ')
 }
@@ -229,8 +232,8 @@ function exactAsm (buf) {
       ? 'it contains a truncated push'
       : ops.some(o => isPush(o) && o.code !== TAIL && opSize(pushOp(pushValue(o))) !== opSize(o))
         ? 'a push is not minimally encoded, and ASM cannot say how data was pushed'
-        : /OP_UNKNOWN|\bOP_INVALIDOPCODE\b/.test(asm) || ops.some(o => o.code >= 0 && !isPush(o) && !NAMES[o.code])
-          ? 'it uses an opcode that has no name in ASM'
+        : ops.some(o => o.code >= 0 && !isPush(o) && !NAMES[o.code])
+          ? 'it uses an opcode that has no name, which @smartledger/bsv reads back from ASM only from 9.11.1'
           : !/\bOP_/.test(asm)
               ? 'it is only data pushes, and ASM with no opcodes reads back as hex'
               : 'its ASM reads back as a different script'

test/unit.test.js

@@ -199,6 +199,8 @@ test('ASM output reads back byte for byte, or is refused', () => {
     assert.ok(toBuffer(exactAsm(buf)).equals(buf), src)
   }
   assert.throws(() => exactAsm(Buffer.from('4c03aabbcc51', 'hex')), /not minimally encoded/)
+  // An unnamed opcode is written as its raw byte, 0xba.
+  assert.strictEqual(exactAsm(Buffer.from('51ba6a05aabbccddee', 'hex')), 'OP_1 0xba OP_RETURN aabbccddee')
   assert.throws(() => exactAsm(Buffer.from('516a05aabb', 'hex')), /truncated push/)
   assert.throws(() => exactAsm(Buffer.from('4c50' + 'ab'.repeat(80), 'hex')), /only data pushes/)