From bad039e7a995fb236ce8b94b7aada22209b960de Mon Sep 17 00:00:00 2001
From: itsmattkc <itsmattkc@gmail.com>
Date: Fri, 5 Jun 2020 17:21:46 +1000
Subject: [PATCH] playbackcache: don't invalidate if the cache has no length

Prevents zero-length invalidations.
---
 app/render/playbackcache.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/app/render/playbackcache.cpp b/app/render/playbackcache.cpp
index 3ac37b808..b94ed08e0 100644
--- a/app/render/playbackcache.cpp
+++ b/app/render/playbackcache.cpp
@@ -39,6 +39,10 @@ void PlaybackCache::InvalidateAll()
 {
   QMutexLocker locker(lock());
 
+  if (length_.isNull()) {
+    return;
+  }
+
   TimeRange invalidate_range(0, length_);
 
   NoLockInvalidate(invalidate_range);
@@ -132,6 +136,8 @@ void PlaybackCache::Shift(const rational &from, const rational &to)
 
 void PlaybackCache::NoLockInvalidate(const TimeRange &r)
 {
+  Q_ASSERT(r.in() != r.out());
+
   invalidated_.InsertTimeRange(r);
 
   RemoveRangeFromJobs(r);