transaction: better errors for signature methods

Closes #868

lib/errors/spec.js

@@ -58,6 +58,9 @@ module.exports = [{
       }, {
         name: 'NeedMoreInfo',
         message: format('{0}')
+      }, {
+        name: 'UnableToVerifySignature',
+        message: format('Unable to verify signature: {0}')
       }, {
         name: 'FeeError',
         message: format('Fees are not correctly set {0}'),

lib/transaction/transaction.js

@@ -657,6 +657,14 @@ Transaction.prototype.applySignature = function(signature) {
 };
 
 Transaction.prototype.isFullySigned = function() {
+  _.each(this.inputs, function(input) {
+    if (input.isFullySigned === Input.prototype.isFullySigned) {
+      throw new errors.Transaction.UnableToVerifySignature(
+        'Unrecognized script kind, or not enough information to execute script.' +
+        'This usually happens when creating a transaction from a serialized transaction'
+      );
+    }
+  });
   return _.all(_.map(this.inputs, function(input) {
     return input.isFullySigned();
   }));
@@ -664,6 +672,12 @@ Transaction.prototype.isFullySigned = function() {
 
 Transaction.prototype.isValidSignature = function(signature) {
   var self = this;
+  if (this.inputs[signature.inputIndex].isValidSignature === Input.prototype.isValidSignature) {
+    throw new errors.Transaction.UnableToVerifySignature(
+      'Unrecognized script kind, or not enough information to execute script.' +
+      'This usually happens when creating a transaction from a serialized transaction'
+    );
+  }
   return this.inputs[signature.inputIndex].isValidSignature(self, signature);
 };
 

test/transaction/transaction.js

@@ -197,6 +197,22 @@ describe('Transaction', function() {
     satoshis: 1e8
   };
 
+  describe('not enough information errors', function() {
+    it('fails when Inputs are not subclassed and isFullySigned is called', function() {
+      var tx = new Transaction(tx_1_hex);
+      expect(function() {
+        return tx.isFullySigned();
+      }).to.throw(errors.Transaction.UnableToVerifySignature);
+    });
+
+    it('fails when Inputs are not subclassed and verifySignature is called', function() {
+      var tx = new Transaction(tx_1_hex);
+      expect(function() {
+        return tx.isValidSignature({inputIndex: 0});
+      }).to.throw(errors.Transaction.UnableToVerifySignature);
+    });
+  });
+
   describe('checked serialize', function() {
     it('fails if no change address was set', function() {
       var transaction = new Transaction()