[Adaptive] HorizontalTwoPaneStrategy does not split equally with splitFraction 0.5

[ammargitham]

Description
When using TwoPane with HorizontalTwoPaneStrategy(splitFraction = 0.5f), the first and the second composables do not have equal width.

Steps to reproduce
Code:

var panelASize by remember {
    mutableStateOf(IntSize.Zero)
}
var panelBSize by remember {
    mutableStateOf(IntSize.Zero)
}

TwoPane(
    first = {
        Box(
            modifier = Modifier
                .fillMaxSize()
                .background(Color.Yellow)
                .onSizeChanged { panelASize = it }
        ) {
            Text(
                modifier = Modifier.align(Alignment.Center),
                text = "Panel A\n${panelASize.width}",
                style = MaterialTheme.typography.displayLarge,
            )
        }
    },
    second = {
        Box(
            modifier = Modifier
                .fillMaxSize()
                .background(Color.Cyan)
                .onSizeChanged { panelBSize = it }
        ) {
            Text(
                modifier = Modifier.align(Alignment.Center),
                text = "Panel B\n${panelBSize.width}",
                style = MaterialTheme.typography.displayLarge,
            )
        }
    },
    strategy = HorizontalTwoPaneStrategy(splitFraction = 0.5f),
    displayFeatures = calculateDisplayFeatures(activity = this@MainActivity),
    foldAwareConfiguration = FoldAwareConfiguration.VerticalFoldsOnly,
)

Expected behavior
Expected widths of Panel A and B to be equal.

Screenshots:

Emulator: Resizable (Experimental) API 33 (Tablet mode)

Emulator: Pixel Fold API 34

[alexvanyo]

Have you been able to reproduce this on a physical device?

[ammargitham]

Sorry, I don't own any tablet or foldable. So can't test on a real device.

[alexvanyo]

I was able to reproduce that behavior on the resizable emulator with the following steps:

• Open the resizable emulator
• Toggle to the "Foldable" configuration. This causes the list of the display features to include the folding feature for the foldable.
• Toggle to the "Tablet" configuration. This doesn't remove the folding feature, so the old folding feature at x = 884 is still incorrectly present in the tablet configuration.
• The (erroneous) vertical fold is automatically avoided by the TwoPane logic, which leads to the unexpected sizing in the screenshot above

Reported that issue here: https://issuetracker.google.com/issues/295909182

I couldn't repro on the Pixel Fold emulator, but my Pixel Fold emulator right now is not reporting any folding features at all. 🙃

I'm going to close this here in accompanist as I suspect the issues here lie upstream in the emulator configuration, where erroneous folding features are causing unintuitive behavior.