Do not turn OP_1NEGATE in scriptSig into 0x0181 in signing code

Co-authored-by: Samuel Dobson <[email protected]>

Author: sipa

src/script/sign.cpp

@@ -186,6 +186,8 @@ static CScript PushAll(const std::vector<valtype>& values)
             result << OP_0;
         } else if (v.size() == 1 && v[0] >= 1 && v[0] <= 16) {
             result << CScript::EncodeOP_N(v[0]);
+        } else if (v.size() == 1 && v[0] == 0x81) {
+            result << OP_1NEGATE;
         } else {
             result << v;
         }

src/test/transaction_tests.cpp

@@ -361,6 +361,8 @@ static CScript PushAll(const std::vector<valtype>& values)
             result << OP_0;
         } else if (v.size() == 1 && v[0] >= 1 && v[0] <= 16) {
             result << CScript::EncodeOP_N(v[0]);
+        } else if (v.size() == 1 && v[0] == 0x81) {
+            result << OP_1NEGATE;
         } else {
             result << v;
         }