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Missing documentation for the new params:

dartdoc:stdout: Generating docs for library cupertino from package:flutter/cupertino.dart...
dartdoc:stderr:   error: undefined macro [flutter.widgets.editableText.cursorOpacityAnimates]
dartdoc:stderr:     from cupertino.CupertinoTextField.cursorOpacityAnimates: (file:///tmp/flutter%20sdk/packages/flutter/lib/src/cupertino/text_field.dart:666:14)
...
dartdoc:stderr:   error: undefined macro [flutter.widgets.editableText.cursorOpacityAnimates]
dartdoc:stderr:     from material.TextField.cursorOpacityAnimates: (file:///tmp/flutter%20sdk/packages/flutter/lib/src/material/text_field.dart:586:15)

@jmagman I've updated the docs. Not sure why that macro didn't work, but it's building now.

The macro wasn't working because there wasn't a definition for it. If you'd like to use the handy macro feature in the docs, you can add a @template marker with the same syntax that's used on the neighboring field:

  /// {@template flutter.widgets.editableText.cursorRadius}
  /// How rounded the corners of the cursor should be.
  ///
  /// By default, the cursor has no radius.
  /// {@endtemplate}
  final Radius? cursorRadius;

  /// Whether the cursor will animate from fully transparent to fully opaque
  /// during each cursor blink.
  ///
  /// By default, the cursor opacity will animate on iOS platforms and will not
  /// animate on Android platforms.
  final bool cursorOpacityAnimates;

That {@template etc. syntax is what defines the meaning of {@macro flutter.widgets.editableText.cursorRadius}, and you can do the same thing to make it work the same way for cursorOpacityAnimates.

@gnprice Oh nice, thanks for the tip!

@justinmc I've added the macro for the docs and added tests you suggested for material and cupertino. I have also manually verified that the toggle overrides the default platform value correctly on a linux computer and mac.

Also, have you verified that turning this off does indeed fix the CPU performance issue? I see you commented on the issue with some hard numbers, were those taken from disabling and enabling this on EditableText?

Correct, I tested this by disabling/enabling the parameter in the text field examples. Nothing but the text field is present in the test app.

I have checked the CPU usage on multiple platforms (linux, macOS, iOS, windows) on physical devices, not emulators and in release mode. Each platform shows the same trend -- with the animation enabled I see a constant 10-16% cpu usage and with it disabled I see 0% cpu usage.

On desktop platforms I measured CPU using htop and the systems system monitor program. For iOS I used xCode's profiler/monitor thing.

@justinmc Sweet, thanks for the review! What exactly is the process for getting this merged?

Sorry @Blquinn, the process was just to find a secondary reviewer, which @werainkhatri has been nice enough to provide. Now this will merge automatically when the tree is green.

Awesome; no problem at all. Thank you both!

The tree is green, but the "Google testing" check for this PR seems to have gotten stuck:

• Google testing fails to report status to GitHub #123289

One workaround is to update the PR so the check gets restarted. I'm not sure if there are other workarounds a Googler could apply.