From 0a052355bbb6ab99e4267d28ad2a968a9a908a99 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <braydon@bitpay.com>
Date: Mon, 16 Nov 2015 12:49:31 -0500
Subject: [PATCH] Script: Account for reverseMap name inconsistencies

There are a few cases where the opcode name doesn't match the name exactly.
These are mostly related with data pushes, and the cases for `OP_0` and `OP_1NEGATE` were
not handled as data pushes as the buf.length was 0. This adds these exceptions to the
`_chunkToString` method on Script.

References:
- https://github.com/bitcoin/bitcoin/blob/e54ebbf6009716a7abcd4d8d3f7bd910e88decdc/src/script/script.cpp#L13
- https://github.com/bitcoin/bitcoin/blob/e54ebbf6009716a7abcd4d8d3f7bd910e88decdc/src/core_write.cpp#L75
---
 lib/script/script.js | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/lib/script/script.js b/lib/script/script.js
index 176efdb..24c31c9 100644
--- a/lib/script/script.js
+++ b/lib/script/script.js
@@ -228,7 +228,21 @@ Script.prototype._chunkToString = function(chunk, type) {
   if (!chunk.buf) {
     // no data chunk
     if (typeof Opcode.reverseMap[opcodenum] !== 'undefined') {
-      str = str + ' ' + Opcode(opcodenum).toString();
+      if (asm) {
+        // A few cases where the opcode name differs from reverseMap
+        // aside from 1 to 16 data pushes.
+        if (opcodenum === 0) {
+          // OP_0 -> 0
+          str = str + ' 0';
+        } else if(opcodenum === 79) {
+          // OP_1NEGATE -> 1
+          str = str + ' -1';
+        } else {
+          str = str + ' ' + Opcode(opcodenum).toString();
+        }
+      } else {
+        str = str + ' ' + Opcode(opcodenum).toString();
+      }
     } else {
       var numstr = opcodenum.toString(16);
       if (numstr.length % 2 !== 0) {
@@ -242,7 +256,7 @@ Script.prototype._chunkToString = function(chunk, type) {
     }
   } else {
     // data chunk
-    if (opcodenum === Opcode.OP_PUSHDATA1 ||
+    if (!asm && opcodenum === Opcode.OP_PUSHDATA1 ||
       opcodenum === Opcode.OP_PUSHDATA2 ||
       opcodenum === Opcode.OP_PUSHDATA4) {
       str = str + ' ' + Opcode(opcodenum).toString();