Bug 172557 – Layout Test media/track/track-cue-rendering-horizontal.html is a flaky failure

• Component: New Bugs
• Status: RESOLVED CONFIGURATION CHANGED

[Matt Lewis]

The test media/track/track-cue-rendering-horizontal.html is a flaky failure on macOS WK1 Debug

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=media%2Ftrack%2Ftrack-cue-rendering-horizontal.html

https://build.webkit.org/results/Apple%20Sierra%20Debug%20WK1%20(Tests)/r217386%20(1425)/results.html
https://build.webkit.org/builders/Apple%20Sierra%20Debug%20WK1%20(Tests)/builds/1425

diff:
--- /Volumes/Data/slave/sierra-debug-tests-wk1/build/layout-test-results/media/track/track-cue-rendering-horizontal-expected.txt
+++ /Volumes/Data/slave/sierra-debug-tests-wk1/build/layout-test-results/media/track/track-cue-rendering-horizontal-actual.txt
@@ -22,43 +22,55 @@
   RenderVideo {VIDEO} at (0,0) size 320x240
 layer at (8,8) size 320x240
   RenderFlexibleBox {DIV} at (0,0) size 320x240
-layer at (8,8) size 320x240
+layer at (8,8) size 320x240 scrollHeight 265
   RenderBlock (relative positioned) {DIV} at (0,0) size 320x240 [color=#FFFFFF]
-layer at (8,8) size 320x14
-  RenderBlock (positioned) {DIV} at (0,0) size 320x14
-    RenderBlock {DIV} at (24,0) size 272x14
-      RenderInline {SPAN} at (0,0) size 271x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 271x14
-          text run at (0,0) width 271: "Cue 1: should be positioned at the top of the video."
-layer at (8,22) size 320x14
-  RenderBlock (positioned) {DIV} at (0,14) size 320x14
-    RenderBlock {DIV} at (11,0) size 298x14
-      RenderInline {SPAN} at (0,0) size 298x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 298x14
-          text run at (0,0) width 298: "Cue 2: should be the second cue and not overlap cue 1."
-layer at (8,36) size 320x14
-  RenderBlock (positioned) {DIV} at (0,28) size 320x14
-    RenderBlock {DIV} at (13,0) size 294x14
-      RenderInline {SPAN} at (0,0) size 293x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 293x14
-          text run at (0,0) width 293: "Cue 3: should become the third line from top to bottom."
-layer at (8,78) size 320x14
-  RenderBlock (positioned) {DIV} at (0,70) size 320x14
-    RenderBlock {DIV} at (19,0) size 282x14
-      RenderInline {SPAN} at (0,0) size 281x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 281x14
-          text run at (0,0) width 281: "Cue 4: should be fixed positioned around the middle."
-layer at (8,234) size 320x14
-  RenderBlock (positioned) {DIV} at (0,226) size 320x14
-    RenderBlock {DIV} at (16,0) size 288x14
-      RenderInline {SPAN} at (0,0) size 287x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 287x14
-          text run at (0,0) width 287: "Cue 5: should be displayed at the bottom of the video."
-layer at (8,220) size 320x14
-  RenderBlock (positioned) {DIV} at (0,212) size 320x14
-    RenderBlock {DIV} at (22,0) size 276x14
-      RenderInline {SPAN} at (0,0) size 275x14 [bgcolor=#000000CC]
-        RenderText {#text} at (0,0) size 275x14
-          text run at (0,0) width 275: "Cue 6: should be on top of bottom positioned cue 5."
+layer at (8,8) size 320x50
+  RenderBlock (positioned) {DIV} at (0,0) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 304x50 [bgcolor=#000000CC]
+        RenderText {#text} at (11,0) size 304x50
+          text run at (11,0) width 298: "Cue 1: should be positioned at"
+          text run at (308,0) width 7: " "
+          text run at (63,25) width 194: "the top of the video."
+layer at (8,58) size 320x50
+  RenderBlock (positioned) {DIV} at (0,50) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 288x50 [bgcolor=#000000CC]
+        RenderText {#text} at (19,0) size 288x50
+          text run at (19,0) width 282: "Cue 2: should be the second"
+          text run at (300,0) width 7: " "
+          text run at (30,25) width 260: "cue and not overlap cue 1."
+layer at (8,108) size 320x50
+  RenderBlock (positioned) {DIV} at (0,100) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 312x50 [bgcolor=#000000CC]
+        RenderText {#text} at (7,0) size 312x50
+          text run at (7,0) width 306: "Cue 3: should become the third"
+          text run at (312,0) width 7: " "
+          text run at (47,25) width 226: "line from top to bottom."
+layer at (8,158) size 320x50
+  RenderBlock (positioned) {DIV} at (0,150) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 290x50 [bgcolor=#000000CC]
+        RenderText {#text} at (50,0) size 290x50
+          text run at (50,0) width 220: "Cue 4: should be fixed"
+          text run at (269,0) width 7: " "
+          text run at (15,25) width 290: "positioned around the middle."
+layer at (8,223) size 320x50 backgroundClip at (8,8) size 320x240 clip at (8,8) size 320x240
+  RenderBlock (positioned) {DIV} at (0,215) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 297x50 [bgcolor=#000000CC]
+        RenderText {#text} at (15,0) size 297x50
+          text run at (15,0) width 290: "Cue 5: should be displayed at"
+          text run at (304,0) width 8: " "
+          text run at (45,25) width 230: "the bottom of the video."
+layer at (8,223) size 320x50 backgroundClip at (8,8) size 320x240 clip at (8,8) size 320x240
+  RenderBlock (positioned) {DIV} at (0,215) size 320x50
+    RenderBlock {DIV} at (0,0) size 320x50
+      RenderInline {SPAN} at (0,0) size 266x50 [bgcolor=#000000CC]
+        RenderText {#text} at (30,0) size 266x50
+          text run at (30,0) width 260: "Cue 6: should be on top of"
+          text run at (289,0) width 7: " "
+          text run at (40,25) width 240: "bottom positioned cue 5."
 layer at (8,238) size 320x10
   RenderButton {BUTTON} at (0,230) size 320x10

[Alexey Proskuryakov]

-layer at (8,8) size 320x240
+layer at (8,8) size 320x240 scrollHeight 265

Antoine, Simon, does this means that scrolling occurred? I don't see anything in the test that would perform scrolling. Could it be a preceding test leaking a UI side action?

-layer at (8,8) size 320x14
+layer at (8,8) size 320x50

And all of these are different height - what does that imply?

[Simon Fraser (smfr)]

(In reply to Alexey Proskuryakov from comment #1)
> -layer at (8,8) size 320x240
> +layer at (8,8) size 320x240 scrollHeight 265
> 
> Antoine, Simon, does this means that scrolling occurred? I don't see
> anything in the test that would perform scrolling. Could it be a preceding
> test leaking a UI side action?

I don't think that means it's scrolled; it just overflow:scroll and that's how big the content is.

> -layer at (8,8) size 320x14
> +layer at (8,8) size 320x50
> 
> And all of these are different height - what does that imply?

No idea. Maybe media people can say.

[Ahmad Saleem]

Removed in https://github.com/WebKit/WebKit/commit/a39bd42ad87d82a3bea0fa6eac107376a973cf7c

Nothing to do here.