Add test imgPhoto-14.5 exercising the fix for [fbaed1f66b]. The GIF decoder didn't manage deferred clear code. This test passes with the fix [340cad7a] and fails before that fix.

1 files changed, 13 insertions, 1 deletions

diff --git a/tests/imgPhoto.test b/tests/imgPhoto.test
index 0126ad9..f00d8eb 100644
--- a/tests/imgPhoto.test
+++ b/tests/imgPhoto.test
@@ -1201,7 +1201,19 @@ test imgPhoto-14.4 {GIF buffer overflow} -setup {
 } -cleanup {
     image delete $i
 } -returnCodes error -result {malformed image}
-
+test imgPhoto-14.5 {Bug [fbaed1f66b] - GIF decoder with deferred clear code} -setup {
+    set fileName [file join [file dirname [info script]] deferredClearCode.gif]
+} -body {
+    # This erroneously produced "malformed image" error.
+    # The deferredClearCode.gif image only has two frames, and calling for -index 2
+    # simply is an easy way to trigger the problem of improper management of a
+    # deferred clear code. It's easier to show the problem using a GIF image with
+    # several frames. With just a single frame, the effect is that the GIF decoder
+    # bailed out before the end of the image reading, which produces black pixels
+    # at the bottom of the image but no "malformed image error".
+    image create photo -file $fileName -format "gif -index 2"
+} -returnCodes error -result {no image data for this index}
+ 
 test imgPhoto-15.1 {photo images can fail to allocate memory gracefully} -constraints {
     nonPortable
 } -body {