[macOS] - Text deltas are buggy with special characters #101013
Description
On Mac OS, entering special characters with text deltas, such as opt+u and opt+n, results in buggy behavior.
This problem might exist on Windows and Linux. I don't have access to machines to test it.
When entering a "˜" with opt+n, for example, instead of an insertion delta, we get a replacement delta. This results in the removal of a character that the user didn't want to remove.
Screen.Recording.2022-03-29.at.8.17.58.PM.mov
flutter: INFO: 2022-03-29 20:24:02.300713: User tapped at text offset 1
flutter: FINE: 2022-03-29 20:24:02.306272: Is attached to input client? true
flutter: INFO: 2022-03-29 20:24:02.313812: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:02.313896: - delta: Instance of 'TextEditingDeltaNonTextUpdate'
flutter: INFO: 2022-03-29 20:24:02.314053: - old text: Hello, world!
flutter: INFO: 2022-03-29 20:24:02.315779: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:02.315834: - delta: Instance of 'TextEditingDeltaNonTextUpdate'
flutter: INFO: 2022-03-29 20:24:02.315868: - old text: Hello, world!
flutter: INFO: 2022-03-29 20:24:03.812027: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:03.812117: - delta: Instance of 'TextEditingDeltaReplacement'
flutter: INFO: 2022-03-29 20:24:03.812157: - old text: Hello, world!
flutter: INFO: 2022-03-29 20:24:03.812337: - replacing: e
flutter: INFO: 2022-03-29 20:24:03.812439: - with text: ˜
flutter: INFO: 2022-03-29 20:24:03.812559: - replaced range: TextRange(start: 1, end: 2)
flutter: INFO: 2022-03-29 20:24:03.813473: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:03.813533: - delta: Instance of 'TextEditingDeltaNonTextUpdate'
flutter: INFO: 2022-03-29 20:24:03.813566: - old text: H˜llo, world!
flutter: INFO: 2022-03-29 20:24:05.321640: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:05.321806: - delta: Instance of 'TextEditingDeltaNonTextUpdate'
flutter: INFO: 2022-03-29 20:24:05.321881: - old text: H˜llo, world!
flutter: INFO: 2022-03-29 20:24:05.322854: Received list of text editing deltas.
flutter: INFO: 2022-03-29 20:24:05.322958: - delta: Instance of 'TextEditingDeltaNonTextUpdate'
flutter: INFO: 2022-03-29 20:24:05.323023: - old text: H˜llo, world!
You can reproduce this same situation by copying the implementation of simple_deltas_input.dart from this PR:
https://github.com/superlistapp/super_editor/pull/500/files#diff-d8a7604dfb54eac1f4a86d074736eacdbc9ddcc4430de3738b0360ab77584aa2
Also, if you enter opt+u, it also produces a replacement delta, and sometimes the delta tries to insert the character at unexpected positions, possibly resulting in an infinite loop going back-and-forth with the IME.
Flutter version
Flutter 2.10.3 • channel stable • https://github.com/flutter/flutter.git
Framework • revision 7e9793dee1 (4 weeks ago) • 2022-03-02 11:23:12 -0600
Engine • revision bd539267b4
Tools • Dart 2.16.1 • DevTools 2.9.2