Disable caret at end of line detection in Chromium

[michaelDCurran]

Link to issue number:

More broadly fixes #17039

Summary of the issue:

In PR #16745, code was added to detect the caret at end of lines in Mozilla-compatible edit areas, so as to not report the next line when on the final insertion point of the line before.
Although this works great in Firefox and other Gecko-based apps, it does not work at all in Chromium due to Chromium not correctly
implementing IAccessibleText::textAtOffset with IA2_OFFSET_CARET.
More importantly, this is a very costly check in VS code, which has a noticeable performance hit when arrowing up and down large files (issue #17039), for no gain.
PR #17051 successfully fixed the performance hit in VS code by disabling caret at end of line detection just for VS Code. But it was pointed out that there are several VS Code variants including VS Code.dev which require this also.

Description of user facing changes

NVDA is no longer as sluggish when arrowing up and down large fles in VS code and otherChromium-based applications.

Description of development approach

• Remoe the VSCodeditor and VSCodeEditorTextInfo classes from the VS ode appModule introduced in pr VS Code is no longer as sluggish when arrowing up and down through large files #17051.
• Add Editor and EditorTextInfo classes to NVDAObjects.IAccessible.chromium which are used in Chromium where ever NVDAObject.IAccessible.ia2Web.Editor is used. These classes disable caret at end of line detection for any chromium edit area.

Testing strategy:

Retested steps in #17039, ensuring that the performance hit is stll gone in VS Code.

Known issues with pull request:

None known.

Code Review Checklist:

• Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• API is compatible with existing add-ons.
• Security precautions taken.

Summary by CodeRabbit

• New Features

  • Introduced enhanced accessibility features for text areas in Chromium-based applications.
  • Added support for better text editing capabilities with new Editor and EditorTextInfo classes.

• Bug Fixes

  • Removed unnecessary caret detection methods to improve performance and accuracy in Chromium and VSCode environments.

• Refactor

  • Streamlined code by eliminating outdated classes and methods associated with text handling in Visual Studio Code.

[coderabbitai]

Walkthrough

The changes introduce new classes for handling text areas in Chromium-based applications and remove redundant classes related to text handling in Visual Studio Code. The EditorTextInfo and Editor classes enhance accessibility features, while the removal of VSCodeEditor and VSCodeEditorTextInfo simplifies the codebase, addressing performance issues noted in the linked issue.

Changes

Files	Change Summary
source/NVDAObjects/IAccessible/chromium.py	Added EditorTextInfo and Editor classes to improve text area handling; modified findExtraOverlayClasses to prioritize Editor.
source/appModules/code.py	Removed VSCodeEditorTextInfo and VSCodeEditor classes; updated VSCodeDocument to remove assignment of textInfo.

Assessment against linked issues

Objective	Addressed	Explanation
NVDA responsiveness in VS Code editors (Issue #17039)	✅
Remove unnecessary classes and methods for performance	✅

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Recent review details

Configuration used: .coderabbit.yml
Review profile: CHILL

Commits

Files that changed from the base of the PR and between 69b9ce4 and 5373ae4.

Files selected for processing (2)

• source/NVDAObjects/IAccessible/chromium.py (2 hunks)
• source/appModules/code.py (1 hunks)

Files skipped from review due to trivial changes (1)

• source/appModules/code.py

Additional context used

Path-based instructions (1)

source/NVDAObjects/IAccessible/chromium.py (2)

Pattern **/*: Focus on code smells, logic errors, edge cases, missing test cases, security flaws and serious issues. Avoid commenting on minor issues such as linting, formatting and style issues. This project uses tabs instead of spaces, do not suggest usage of spaces over tabs. Are there any 'red flags' in this code that might warrant closer investigation from a security standpoint? Explain what makes them suspicious. When providing code suggestions, particularly when requested, ensure GitHub's suggestion format is used, i.e.: suggestion <code changes>

---

Pattern **/*.py: _, pgettext, ngettext, and ngettext are defined globally, errors for this being undefined can be ignored.

Additional comments not posted (3)

source/NVDAObjects/IAccessible/chromium.py (3)

169-179: LGTM!

The method _isCaretAtEndOfLine is correctly implemented to address performance issues in Chromium. The comments provide a clear explanation of the rationale.

The code changes are approved.

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182-185: LGTM!

The class Editor correctly sets TextInfo to EditorTextInfo, ensuring that the performance improvements are applied.

The code changes are approved.

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210-211: LGTM!

The modification ensures that the Editor class is prioritized, which is necessary for the performance improvements to take effect.

The code changes are approved.

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