Send -1 for empty composition range

[knopp]

flutter/flutter#77600

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It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat.

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[stuartmorgan-g]

I missed that we lost this conversation in the model unification PR.

Could we get some unit tests set up for this so we don't regress it again?

[cbracken]

Thanks for the fix! As Stuart says, a test would be fantastic here. Happy to help on that front.

[knopp]

@cbracken, any pointers as to what the test should look like is appreciated.

[stuartmorgan-g]

https://github.com/flutter/engine/blob/7bc7fdb461734fff9fdf35179a00e692fb3d41fe/shell/platform/darwin/macos/framework/Source/FlutterViewControllerTest.mm has some tests that demonstrate validating calls made on a channel. You could make the text input plugin's handleMethodCall: visible for testing (to minimize coupling to private API), then send some synthetic message in via that and ensure that you get the expected TextInputClient.updateEditingState state object sent to the engine.

[knopp]

@stuartmorgan, @cbracken, I added a test for this. Anything else or is this good to go?

[cbracken]

Thanks @knopp. Taking a quick look. Looks like it needs a quick rebase for shell/platform/darwin/macos/BUILD.gn in the meantime.

[cbracken]

LGTM. Thank you for adding the test.

[cbracken]

I've kicked the build_and_test_linux presubmit. Re-run: https://cirrus-ci.com/task/6264967797145600

[chinmaygarde]

The test failure is a known flake. I've filed a report and re-run the test.