From 1eef0ec19c89a9f451ce0c37b854ee29dbde5a85 Mon Sep 17 00:00:00 2001
From: Zahary Karadjov <zahary@gmail.com>
Date: Sat, 22 Jan 2022 13:00:50 +0200
Subject: [PATCH] Obtain a fresh span after flushing

---
 faststreams/outputs.nim | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/faststreams/outputs.nim b/faststreams/outputs.nim
index ba8f55f..35c7162 100644
--- a/faststreams/outputs.nim
+++ b/faststreams/outputs.nim
@@ -132,8 +132,11 @@ template flushImpl(s: OutputStream, awaiter, writeOp, flushOp: untyped) =
   fsAssert s.extCursorsCount == 0
   if s.vtable != nil:
     if s.buffers != nil:
+      let runway = s.span.len
       trackWrittenTo(s.buffers, s.span.startAddr)
       awaiter s.vtable.writeOp(s, nil, 0)
+      s.span = getWritableSpan(s.buffers)
+      s.spanEndPos += s.span.len - runway
 
     if s.vtable.flushOp != nil:
       awaiter s.vtable.flushOp(s)