test: improve TileCacheTests

Sometimes core renderes with sub-pixel differences
(the crosshair at the corners of the Writer pages
show line anti-aliasing differences). This causes
failure of the tests that count the tile deduplication.

We now tolerate when we get an unchanged tile twice,
assuming it was due to such a rendering difference,
but we re-trigger another change and this time we
don't expect any extra tiles, no more than two
variations of the anti-aliased crosshair was
observed.

We also move some duplicate code into utility
functions to improve readability and reuse.

Reviewed-on: https://gerrit.libreoffice.org/81196
Reviewed-by: Andras Timar <andras.timar@collabora.com>
Tested-by: Andras Timar <andras.timar@collabora.com>
(cherry picked from commit 9603597fd1aaecb27893792cfd2d243e450b58b8)

Change-Id: I1a66732dd3443bfbd770d8dc65721571dfa08615
Reviewed-on: https://gerrit.libreoffice.org/81572
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
Tested-by: Ashod Nakashian <ashnakash@gmail.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/kit/Kit.cpp b/kit/Kit.cpp
index d6d255bf1..9eac5dc7e 100644
--- a/kit/Kit.cpp
+++ b/kit/Kit.cpp
@@ -500,8 +500,8 @@ public:
                 }
             }
 
-            LOG_DBG("PNG cache has " << _cache.size() << " items, total size " <<
-                    _cacheSize << " after balance.");
+            LOG_DBG("PNG cache has " << _cache.size() << " items with total size of " <<
+                    _cacheSize << " bytes after balance.");
         }
 
         if (_hashToWireId.size() > CacheWidHardLimit)
@@ -541,6 +541,7 @@ public:
             }
         }
 
+        LOG_DBG("PNG cache with hash " << hash << " missed.");
         return false;
     }