IssueTracker

DataStore Component used: Preferences DataStore Version used: 1.0.0 Devices/Android versions reproduced on: Pixel 5 API 32

When having nested .edit {} calls, execution stops before starting the nested call, we assume due to some sort of deadlock. We ran into this due to an .edit {} call in a deep function call chain from within another .edit {} call. The issue was hard to detect so we believe there should be some help from the library by either providing some lint check, or throwing an exception if this happens.

Example:

scope.launch {
    dataStore.edit { settings ->
        Log.d(TAG, "Starting edit 1")
        val currentCounterValue = settings[EXAMPLE_COUNTER] ?: 0
        settings[EXAMPLE_COUNTER] = currentCounterValue + 1

        Log.d(TAG, "Continuation edit 1")
        dataStore.edit { settings2 ->
            Log.d(TAG, "Starting edit 2")
            val currentCounterValue = settings2[EXAMPLE_COUNTER] ?: 0
            settings2[EXAMPLE_COUNTER] = currentCounterValue + 1
            Log.d(TAG, "Ending edit 2")
        }
        Log.d(TAG, "Ending edit 1")
    }
}

prints

Starting edit 1
Con edit 1
Starting edit 1
Continuation edit 1