Remove IsPushOnlyScript from mempool validation (#1492)

* Remove IsPushOnlyScript from mempool validation

* Fix TestCheckTransactionStandard

domain/consensus/utils/txscript/error.go

@@ -192,7 +192,7 @@ const (
 	// or to be in compressed format as a 32 byte string prefixed with 0x02 or 0x03 to signal oddness.
 	ErrPubKeyFormat
 
-	// ErrCleanStack is returned when after evalution, the stack
+	// ErrCleanStack is returned when after evaluation, the stack
 	// contains more than one element.
 	ErrCleanStack
 

domain/consensus/utils/txscript/script.go

@@ -84,17 +84,6 @@ func isPushOnly(pops []parsedOpcode) bool {
 	return true
 }
 
-// IsPushOnlyScript returns whether or not the passed script only pushes data.
-//
-// False will be returned when the script does not parse.
-func IsPushOnlyScript(script []byte) (bool, error) {
-	pops, err := parseScript(script)
-	if err != nil {
-		return false, err
-	}
-	return isPushOnly(pops), nil
-}
-
 // parseScriptTemplate is the same as parseScript but allows the passing of the
 // template list for testing purposes. When there are parse errors, it returns
 // the list of parsed opcodes up to the point of failure along with the error.

domain/consensus/utils/txscript/script_test.go

@@ -3723,6 +3723,17 @@ func TestPushedData(t *testing.T) {
 	}
 }
 
+// isPushOnlyScript returns whether or not the passed script only pushes data.
+//
+// False will be returned when the script does not parse.
+func isPushOnlyScript(script []byte) (bool, error) {
+	pops, err := parseScript(script)
+	if err != nil {
+		return false, err
+	}
+	return isPushOnly(pops), nil
+}
+
 // TestHasCanonicalPush ensures the canonicalPush function works as expected.
 func TestHasCanonicalPush(t *testing.T) {
 	t.Parallel()
@@ -3734,8 +3745,8 @@ func TestHasCanonicalPush(t *testing.T) {
 				err)
 			continue
 		}
-		if result, _ := IsPushOnlyScript(script); !result {
-			t.Errorf("IsPushOnlyScript: test #%d failed: %x\n", i,
+		if result, _ := isPushOnlyScript(script); !result {
+			t.Errorf("isPushOnlyScript: test #%d failed: %x\n", i,
 				script)
 			continue
 		}
@@ -3760,8 +3771,8 @@ func TestHasCanonicalPush(t *testing.T) {
 			t.Errorf("StandardPushesTests test #%d unexpected error: %v\n", i, err)
 			continue
 		}
-		if result, _ := IsPushOnlyScript(script); !result {
-			t.Errorf("StandardPushesTests IsPushOnlyScript test #%d failed: %x\n", i, script)
+		if result, _ := isPushOnlyScript(script); !result {
+			t.Errorf("StandardPushesTests isPushOnlyScript test #%d failed: %x\n", i, script)
 			continue
 		}
 		pops, err := parseScript(script)
@@ -3889,9 +3900,9 @@ func TestHasCanonicalPushes(t *testing.T) {
 	}
 }
 
-// TestIsPushOnlyScript ensures the IsPushOnlyScript function returns the
+// TestIsPushOnly ensures the isPushOnly function returns the
 // expected results.
-func TestIsPushOnlyScript(t *testing.T) {
+func TestIsPushOnly(t *testing.T) {
 	t.Parallel()
 
 	tests := []struct {
@@ -3922,19 +3933,19 @@ func TestIsPushOnlyScript(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		isPushOnly, err := IsPushOnlyScript(test.script)
+		isPushOnly, err := isPushOnlyScript(test.script)
 
 		if isPushOnly != test.expectedResult {
-			t.Errorf("IsPushOnlyScript (%s) wrong result\ngot: %v\nwant: "+
+			t.Errorf("isPushOnlyScript (%s) wrong result\ngot: %v\nwant: "+
 				"%v", test.name, isPushOnly, test.expectedResult)
 		}
 
 		if test.shouldFail && err == nil {
-			t.Errorf("IsPushOnlyScript (%s) expected an error but got <nil>", test.name)
+			t.Errorf("isPushOnlyScript (%s) expected an error but got <nil>", test.name)
 		}
 
 		if !test.shouldFail && err != nil {
-			t.Errorf("IsPushOnlyScript (%s) expected no error but got: %v", test.name, err)
+			t.Errorf("isPushOnlyScript (%s) expected no error but got: %v", test.name, err)
 		}
 	}
 }

domain/miningmanager/mempool/policy.go

@@ -222,19 +222,6 @@ func checkTransactionStandard(tx *consensusexternalapi.DomainTransaction, policy
 				maxStandardSigScriptSize)
 			return txRuleError(RejectNonstandard, str)
 		}
-
-		// Each transaction input signature script must only contain
-		// opcodes which push data onto the stack.
-		isPushOnly, err := txscript.IsPushOnlyScript(txIn.SignatureScript)
-		if err != nil {
-			str := fmt.Sprintf("transaction input %d: IsPushOnlyScript: %t. Error %s", i, isPushOnly, err)
-			return txRuleError(RejectNonstandard, str)
-		}
-		if !isPushOnly {
-			str := fmt.Sprintf("transaction input %d: signature "+
-				"script is not push only", i)
-			return txRuleError(RejectNonstandard, str)
-		}
 	}
 
 	// None of the output public key scripts can be a non-standard script or

domain/miningmanager/mempool/policy_test.go

@@ -235,18 +235,6 @@ func TestCheckTransactionStandard(t *testing.T) {
 			isStandard: false,
 			code:       RejectNonstandard,
 		},
-		{
-			name: "Signature script that does more than push data",
-			tx: consensusexternalapi.DomainTransaction{Version: 0, Inputs: []*consensusexternalapi.DomainTransactionInput{{
-				PreviousOutpoint: dummyPrevOut,
-				SignatureScript: []byte{
-					txscript.OpCheckSigVerify},
-				Sequence: constants.MaxTxInSequenceNum,
-			}}, Outputs: []*consensusexternalapi.DomainTransactionOutput{&dummyTxOut}},
-			height:     300000,
-			isStandard: false,
-			code:       RejectNonstandard,
-		},
 		{
 			name: "Valid but non standard public key script",
 			tx: consensusexternalapi.DomainTransaction{Version: 0, Inputs: []*consensusexternalapi.DomainTransactionInput{&dummyTxIn}, Outputs: []*consensusexternalapi.DomainTransactionOutput{{