txscript: Remove unused isPushOnly function.

txscript/script.go

@@ -161,26 +161,6 @@ func ExtractWitnessProgramInfo(script []byte) (int, []byte, error) {
 	return witnessVersion, witnessProgram, nil
 }
 
-// isPushOnly returns true if the script only pushes data, false otherwise.
-//
-// DEPRECATED.  Use IsPushOnlyScript instead.
-func isPushOnly(pops []parsedOpcode) bool {
-	// NOTE: This function does NOT verify opcodes directly since it is
-	// internal and is only called with parsed opcodes for scripts that did
-	// not have any parse errors.  Thus, consensus is properly maintained.
-
-	for _, pop := range pops {
-		// All opcodes up to OP_16 are data push instructions.
-		// NOTE: This does consider OP_RESERVED to be a data push
-		// instruction, but execution of OP_RESERVED will fail anyways
-		// and matches the behavior required by consensus.
-		if pop.opcode.value > OP_16 {
-			return false
-		}
-	}
-	return true
-}
-
 // IsPushOnlyScript returns whether or not the passed script only pushes data
 // according to the consensus definition of pushing data.
 //
@@ -900,11 +880,7 @@ func GetWitnessSigOpCount(sigScript, pkScript []byte, witness wire.TxWitness) in
 	// Next, we'll check the sigScript to see if this is a nested p2sh
 	// witness program. This is a case wherein the sigScript is actually a
 	// datapush of a p2wsh witness program.
-	sigPops, err := parseScript(sigScript)
-	if err != nil {
-		return 0
-	}
-	if IsPayToScriptHash(pkScript) && isPushOnly(sigPops) &&
+	if IsPayToScriptHash(pkScript) && IsPushOnlyScript(sigScript) &&
 		IsWitnessProgram(sigScript[1:]) {
 		return getWitnessSigOps(sigScript[1:], witness)
 	}