[SuperEditor] Limit tag expansion to caret position (Resolves #2240, #2241, #2242)

[angelosilvestre]

[SuperEditor] Limit tag expansion to caret position. Resolves #2240, #2241, #2242

Steps to reproduce:

1. Go to the "Action Tags" section of the example app
2. Type some text
3. Place the cursor in the middle of the text
4. Type "/"
5. Press backspace
6. Type "/" again

The editor crashes with the following exception:

════════ Exception caught by services library ══════════════════════════════════
The following _Exception was thrown during method call TextInputClient.updateEditingStateWithDeltas:
Exception: removeAttribution() did not satisfy start < 0 and start > end, start: 6, end: 5

When the exception was thrown, this was the stack:
#0      AttributedSpans.removeAttribution (package:attributed_text/src/attributed_spans.dart:514:7)
attributed_spans.dart:514
#1      RemoveTextAttributionsCommand.execute (package:super_editor/src/default_editor/text.dart:1439:15)
text.dart:1439
#2      _DocumentEditorCommandExecutor.executeCommand (package:super_editor/src/core/editor.dart:701:15)
editor.dart:701
#3      Editor._executeCommand (package:super_editor/src/core/editor.dart:304:22)
editor.dart:304
#4      Editor.execute (package:super_editor/src/core/editor.dart:266:30)
editor.dart:266
#5      ActionTagComposingReaction._healCancelledTags (package:super_editor/src/default_editor/text_tokenizing/action_tags.dart:364:23)
action_tags.dart:364
#6      ActionTagComposingReaction.react (package:super_editor/src/default_editor/text_tokenizing/action_tags.dart:286:5)
action_tags.dart:286
#7      Editor._reactToChanges (package:super_editor/src/core/editor.dart:357:16)
editor.dart:357
#8      Editor.endTransaction (package:super_editor/src/core/editor.dart:222:5)
editor.dart:222
... many more

While investigating this, I noticed that typing "/" at the middle of the word causes all the text that comes after the "/" to be part of the action tag:

Screen.Recording.2024-10-29.at.20.23.32.mov

This doesn't look like is expected.

This PR changes this behavior. Now, the tag is expanded only until the caret position:

Screen.Recording.2024-10-29.at.20.25.46.mov

Changing this seems to already fix the issue, and also #2241 and #2242

[angelosilvestre]

@alterhuman @KevinBrendel Would you mind trying this PR?

[alterhuman]

@angelosilvestre thanks for the PR

Working correctly:

• Not crashing when deleting and adding a slash in the middle of a word.
• Automatically cancelling after a space
• Matching action only till caret position

Issues:

1. Moving caret behind the / while still being on the same word doesn't cancel the dropdown. To reproduce:

• Type Some Information
• Add / after o: So/me Information
• Dropdown shows up, move caret behind /, the dropdown hides, then move it again infront of the / the dropdown is visible again but it should've cancelled.

2. Action tag dropdown popping up after reopening a document and focus the caret on the text containing the tag rule /, after the slash. To reproduce:

• Instead of having an empty document add this text:

_document = MutableDocument(nodes: [
      ParagraphNode(
        id: Editor.createNodeId(),
        text: AttributedText("Some Infor/mation"),
      ),
    ]);

• Focus caret at n, the dropdown pops up.

[angelosilvestre]

@alterhuman I fixed the first issue you mentioned. For the second issue, I'm not sure I followed. It doesn't seem to be related to any of the existing issues.

[alterhuman]

@angelosilvestre tested the first issue, it's working correctly. This is the video of second issue, this text is already present in the document when it is opened:

Screen.Recording.2024-10-31.at.6.16.39.PM.mov

Focusing on a word which already has a / inside it when you open the editor, shows the dropdown with the value being the text between / and the caret. This should only happen when I type a slash till the time it's cancelled. It's also happening on opening an editor and then focusing the caret near a word which already has a slash.

[angelosilvestre]

@alterhuman Is this happening on latest main? It doesn't look like it's related to the changes of this PR. If so, can you file a separate issue for this?

[alterhuman]

@angelosilvestre yes this is also happening on main. Will file a separate issue for this. All good for this PR.

[matthew-carroll]

I don't understand this description of endPosition. This method was intended to only look for tags that touch expansionPosition, which is a singular position. There shouldn't be a range involved. So the idea of an endPosition doesn't make sense to me.

[angelosilvestre]

So should we keep this method as it was before and modify the reaction to adjust the reported tag?

[matthew-carroll]

My point was that I don't know what you're trying to do here because it doesn't seem to make sense. I can't answer that question until I first understand what exactly you were trying to do.

[angelosilvestre]

What I'm trying to do is to prevent the tag to expand beyond the caret position. For example, if we have the string "helloworld" and the user types a "/" at the middle, changing it to "hello/world", the string "world" shouldn't be attributed as a tag. The user can input a tag in the middle of a word, but the tag shouldn't expand beyond the caret position.