From 31d3ee899f4331cb75952eceb07b9a8ad7b30e9f Mon Sep 17 00:00:00 2001
From: Richard Moore <github@ricmoo.com>
Date: Wed, 21 Nov 2018 16:23:44 -0500
Subject: [PATCH] Throw exception instead of returning null for
 getDefaultProvider (#351).

---
 src.ts/ethers.ts | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src.ts/ethers.ts b/src.ts/ethers.ts
index 6fe361e7..5a750638 100644
--- a/src.ts/ethers.ts
+++ b/src.ts/ethers.ts
@@ -33,8 +33,14 @@ import { ContractFunction, ContractTransaction, Event, EventFilter } from './con
 // Helper Functions
 
 function getDefaultProvider(network?: utils.Network | string): providers.BaseProvider {
-    let n = utils.getNetwork(network || 'homestead');
-    if (!n || !n._defaultProvider) { return null; }
+    if (network == null) { network = 'homestead'; }
+    let n = utils.getNetwork(network);
+    if (!n || !n._defaultProvider) {
+        errors.throwError('unsupported getDefaultProvider network', errors.UNSUPPORTED_OPERATION, {
+            operation: 'getDefaultProvider',
+            network: network
+        });
+    }
     return n._defaultProvider(providers);
 }