Bug 160744 – AX: Spell check and style attributes should be optional when fetching attributed string

• Component: Accessibility
• Status: RESOLVED FIXED

[Doug Russell]

The overhead of fetching a spell checked attributed string via AX API is substantial. In some cases on the order of 7/8 of the total time spent fetching the string. Overhead for style is much smaller, but still a substantial portion of total time spent fetching an attributed string.

I propose:

1. Introducing two new attributes -
AXSimpleAttributedStringForTextMarkerRange - includes neither style nor spell checking
AXMisspelledAttributedStringForTextMarkerRange - includes both style and spell checking

2. Modifying the existing property AXAttributedStringForTextMarkerRange to not include spell checking, but retain style attributes.

(AXAttributedStringForRange will be unchanged.)

Spell checking is only relevant in editable nodes. Assistive technology clients can detect if they or their ancestors are editable and choose the appropriate attribute.

Style is often not output via speech or braille and in those cases is wasted overhead. Again assistive technology can make contextual decisions to ask for the correct attribute.

Other approaches considered:
Leaving AXAttributedStringForTextMarkerRange unchanged and introducing AXAttributedStringForTextMarkerRangeWithOptions allowing spell checking, style and future attributes to be toggled on and off. The overhead of boxing and unboxing these parameters outweighed the cost savings of skipping any individual attribute except spelling in most cases.

[Radar WebKit Bug Importer]

<rdar://problem/27791714>

[Doug Russell]

Created attachment 285753 [details]
Patch

[Build Bot]

Comment on attachment 285753 [details]
Patch

Attachment 285753 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.webkit.org/results/1847779

New failing tests:
accessibility/mac/attributed-string/attributed-string-for-range-not-misspelled .html
accessibility/mac/attributed-string/attributed-string-for-range.html
accessibility/mac/attributed-string/misspelled-attributed-string-for-range.html
accessibility/mac/bounds-for-range.html
accessibility/mac/attributed-string/simple-attributed-string-for-range.html

[Build Bot]

Created attachment 285758 [details]
Archive of layout-test-results from ews101 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews101  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 285753 [details]
Patch

Attachment 285753 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/1847789

New failing tests:
accessibility/mac/bounds-for-range.html

[Build Bot]

Created attachment 285759 [details]
Archive of layout-test-results from ews107 for mac-yosemite-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews107  Port: mac-yosemite-wk2  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 285753 [details]
Patch

Attachment 285753 [details] did not pass mac-debug-ews (mac):
Output: http://webkit-queues.webkit.org/results/1847798

New failing tests:
accessibility/mac/attributed-string/attributed-string-for-range-not-misspelled .html
accessibility/mac/attributed-string/attributed-string-for-range.html
accessibility/mac/attributed-string/misspelled-attributed-string-for-range.html
accessibility/mac/bounds-for-range.html
accessibility/mac/attributed-string/simple-attributed-string-for-range.html

[Build Bot]

Created attachment 285760 [details]
Archive of layout-test-results from ews115 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews115  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Doug Russell]

Created attachment 285771 [details]
Patch

[Build Bot]

Comment on attachment 285771 [details]
Patch

Attachment 285771 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.webkit.org/results/1848210

New failing tests:
accessibility/mac/bounds-for-range.html

[Build Bot]

Created attachment 285776 [details]
Archive of layout-test-results from ews100 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews100  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 285771 [details]
Patch

Attachment 285771 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/1848243

New failing tests:
accessibility/mac/bounds-for-range.html

[Build Bot]

Created attachment 285777 [details]
Archive of layout-test-results from ews107 for mac-yosemite-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews107  Port: mac-yosemite-wk2  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 285771 [details]
Patch

Attachment 285771 [details] did not pass mac-debug-ews (mac):
Output: http://webkit-queues.webkit.org/results/1848223

New failing tests:
accessibility/mac/bounds-for-range.html

[Build Bot]

Created attachment 285779 [details]
Archive of layout-test-results from ews115 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews115  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Doug Russell]

Created attachment 285812 [details]
Patch

[Doug Russell]

Created attachment 334666 [details]
Updated patch

only introduce one new attribute. omit parameter for style for now. leave AXAttributedStringForTextMarkerRange behavior intact.

[Doug Russell]

Created attachment 334667 [details]
Updated patch

[Doug Russell]

Created attachment 334668 [details]
Updated patch

fix atk build

[Doug Russell]

Created attachment 334669 [details]
Updated patch

try again

[chris fleizach]

Comment on attachment 334669 [details]
Updated patch

View in context: https://bugs.webkit.org/attachment.cgi?id=334669&action=review

> Source/WebCore/ChangeLog:28
> +        AX: Spell check and style attributes should be optional when fetching attributed string

duplicate entries in changelog

> Tools/ChangeLog:44
> +        AX: Spell check and style attributes should be optional when fetching attributed string

duplicate entries

> Tools/DumpRenderTree/AccessibilityUIElement.cpp:886
> +    AccessibilityTextMarkerRange* markerRange = 0;

= nullptr

> Tools/DumpRenderTree/AccessibilityUIElement.cpp:896
> +    AccessibilityTextMarkerRange* markerRange = 0;

ditto

[Doug Russell]

Created attachment 334702 [details]
Updated patch

Updates based on review

[WebKit Commit Bot]

Comment on attachment 334702 [details]
Updated patch

Clearing flags on attachment: 334702

Committed r229080: <https://trac.webkit.org/changeset/229080>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.