2 files changed, 14 insertions, 5 deletions
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 1b94e10071..283d458c8d 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -79,16 +79,20 @@ void RPCTypeCheck(const UniValue& params,
             break;
 
         const UniValue& v = params[i];
-        if (!((v.type() == t) || (fAllowNull && (v.isNull()))))
-        {
-            string err = strprintf("Expected type %s, got %s",
-                                   uvTypeName(t), uvTypeName(v.type()));
-            throw JSONRPCError(RPC_TYPE_ERROR, err);
+        if (!(fAllowNull && v.isNull())) {
+            RPCTypeCheckArgument(v, t);
         }
         i++;
     }
 }
 
+void RPCTypeCheckArgument(const UniValue& value, UniValue::VType typeExpected)
+{
+    if (value.type() != typeExpected) {
+        throw JSONRPCError(RPC_TYPE_ERROR, strprintf("Expected type %s, got %s", uvTypeName(typeExpected), uvTypeName(value.type())));
+    }
+}
+
 void RPCTypeCheckObj(const UniValue& o,
     const map<string, UniValueType>& typesExpected,
     bool fAllowNull,
diff --git a/src/rpc/server.h b/src/rpc/server.h
index fed3d8c90f..52f82866dc 100644
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -78,6 +78,11 @@ bool RPCIsInWarmup(std::string *statusOut);
 void RPCTypeCheck(const UniValue& params,
                   const std::list<UniValue::VType>& typesExpected, bool fAllowNull=false);
 
+/**
+ * Type-check one argument; throws JSONRPCError if wrong type given.
+ */
+void RPCTypeCheckArgument(const UniValue& value, UniValue::VType typeExpected);
+
 /*
   Check for expected keys/value types in an Object.
 */