add fixture to verify input type classification

(cherry picked from commit 8f9d8b7)

test/transaction_builder.js

@@ -125,6 +125,16 @@ describe('TransactionBuilder', function () {
       })
     })
 
+    it('correctly classifies transaction inputs', function() {
+      var tx = Transaction.fromHex(fixtures.valid.classification.hex)
+      var txb = TransactionBuilder.fromTransaction(tx)
+      txb.inputs.forEach(function(i) {
+        assert.strictEqual(i.prevOutType, 'scripthash')
+        assert.strictEqual(i.redeemScriptType, 'multisig')
+        assert.strictEqual(i.signType, 'multisig')
+      })
+    })
+
     fixtures.invalid.fromTransaction.forEach(function (f) {
       it('throws ' + f.exception, function () {
         var tx = Transaction.fromHex(f.txHex)