commit 11d892ce49b6dcfd60998ae3864aa48a7078297d
author Ben Wagner <bungeman@google.com> Fri May 10 11:31:57 2024 -0400
committer SkCQ <skcq-be@skia-corp.google.com.iam.gserviceaccount.com> Fri May 10 16:18:43 2024 +0000
tree 49c729f1fdfac4d7dc770adc5d9ed893a7489aa1
parent 112d6143c6b99ef0610795733342d2ac6bb31453

[fontations] Test to fail to compare gracefully

Avoid crashing in the fontations_compare_ft_* tests when using 16bpp
formats or formats like PDF which don't have pixels in their canvas.

Change-Id: I0f4c84afc60b4710f8dcae7828b75240d54dffd0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/851777
Commit-Queue: Ben Wagner <bungeman@google.com>
Auto-Submit: Ben Wagner <bungeman@google.com>
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>

gm/fontations_ft_compare.cpp

diff --git a/gm/fontations_ft_compare.cpp b/gm/fontations_ft_compare.cpp
index bfdfbcb..ae2aa9e 100644
--- a/gm/fontations_ft_compare.cpp
+++ b/gm/fontations_ft_compare.cpp
@@ -217,11 +217,23 @@
                             diffBitmap.allocPixels(copyImageInfo, 0);
                             highlightDiffBitmap.allocPixels(copyImageInfo, 0);
 
-                            canvas->readPixels(
+                            // comparePixels only handles 4 bpp
+                            if (fontationsBitmap.bytesPerPixel() != 4 ||
+                                freetypeBitmap.bytesPerPixel() != 4)
+                            {
+                                break;
+                            }
+
+                            const bool fontationsRead = canvas->readPixels(
                                     fontationsBitmap, copyBoxFontations.x(), copyBoxFontations.y());
-                            canvas->readPixels(
+                            const bool freetypeRead = canvas->readPixels(
                                     freetypeBitmap, copyBoxFreetype.x(), copyBoxFreetype.y());
 
+                            // readPixels may fail
+                            if (!fontationsRead || !freetypeRead) {
+                                break;
+                            }
+
                             comparePixels(fontationsBitmap,
                                           freetypeBitmap,
                                           &diffBitmap,