Hey all, I have this weird problem that I think might be a bug but I can't be sure. I have this `Ba...

# compose

[Leon]

Hey all,

I have this weird problem that I think might be a bug but I can't be sure. I have this BasicTextField that has a visual transformation applied to it that transforms # Title to Title and changes the size of the text (markdown). It constructs a TransformedText object with an OffsetMapping to account for the 2 characters that have been removed. However there seems to be a bug because when I type in # Title it gets transformed to Title in the text field however when I move the cursor using the arrow keys to the end of the line the application crashes with an out of bounds error. I traced this down and it looks like its an issue with the isLtr() function as it uses selection.end without performing a OffsetMapping conversion on it.

// TextPreparedSelection.kt

    private fun isLtr(): Boolean {
        val direction = layoutResult?.getParagraphDirection(selection.end)
        return direction != ResolvedTextDirection.Rtl
    }

Any ideas on how I could resolve this issue?

[mkrussel]

I would guess you have a bug in your offset mapping.

I was getting similar errors when I return offset - charactersRemoved That caused negative values to be returned from originalToTransformed

[Leon]

I think that the mapping is working since using home and end properly do the mapping. It just seems like the isLtr function is missing a call to perform the transformation

[Zach Klippenstein (he/him) [MOD]]

It’s very possible there's a bug here, please file and we'll look into it

[Leon]

Is there any way that I could patch it on my end (for testing) and maybe put up a PR?

[Zoltan Demant]

https://issuetracker.google.com/issues/214253689

[Leon]

Thank you for sharing that issue!