diff --git a/script/test.py b/script/test.py
index e5dbfd94..27156817 100755
--- a/script/test.py
+++ b/script/test.py
@@ -151,8 +151,12 @@ def run_test(path):
   # Invoke wren and run the test.
   proc = Popen([WREN_APP, path], stdin=PIPE, stdout=PIPE, stderr=PIPE)
   (out, err) = proc.communicate(input_bytes)
-  out = out.decode("utf-8").replace('\r\n', '\n')
-  err = err.decode("utf-8").replace('\r\n', '\n')
+
+  try:
+    out = out.decode("utf-8").replace('\r\n', '\n')
+    err = err.decode("utf-8").replace('\r\n', '\n')
+  except:
+    fails.append('Error decoding output.')
 
   fails = []