[WP-Android 8828] - Detect ArrayIndexOutOfBoundsException exception

[daniloercoli]

This PR does add the ability to detect the ArrayIndexOutOfBoundsException that may happen on Android 8 at the following line of code android.text.DynamicLayout.getBlockIndex(DynamicLayout.java:646) due to a bug present in the Android Platform.
When this exact exception is detected, Aztec reports it to the parent app, by wrapping it into a custom Exception.

The reporting to the parent app happens by re-using the external logging capabilities of Aztec, instead of adding another layer of communication between Aztec and the parent app.
The parent app should just check the type of the exception in the "external" logger implementation passed to Aztec.

Make sure strings will be translated:

• [ x ] If there are new strings that have to be translated, I have added them to the client's strings.xml as a part of the integration PR.

[mzorz]

Nice checking for the line number string here. It makes it fine-grained so we avoid having false positives treated mistakingly 👍
Also, was wondering whether stackTrace could be null, so double checked getStackTraceString() and it seems it will never return null as per this so 👍 as well.

[mzorz]

I think I detected an issue - this line will be different on Android 8.1 (API 27), see this #516

it will be java.lang.ArrayIndexOutOfBoundsException: length=39; index=-1 at android.text.DynamicLayout.getBlockIndex(DynamicLayout.java:648)

If you follow the steps to reproduce in the comment below on Android 8.1 (API 27) it will fail the string comparison @daniloercoli - can we add this other string for the case where Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1?

[daniloercoli]

Nice catch! I've updated the code in 86a0000

Tried to be more verbose as possibile to let future devs to understand quickly why there are those if cases.

[mzorz]

Awesome! Thank you 🙇

[mzorz]

What do you think about moving this class to a package of its own like org.wordpress.aztec.exception or org.wordpress.aztec.util.exception?

[daniloercoli]

Nice idea. Addressed in 876ac04

[mzorz]

LGTM

[mzorz]

FYI just wanted to leave a note that this is easily reproduceable (so the code in this PR can be tested) by disabling the dynamicLayoutCrashPreventer InputFilter like this:

Comment out lines 528 in AztecText.kt like this:

//        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.O || Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1) {
//            // dynamicLayoutCrashPreventer needs to be first in array as these are going to be chained when processed
//            filters = arrayOf(dynamicLayoutCrashPreventer, emptyEditTextBackspaceDetector)
//        } else {
            filters = arrayOf(emptyEditTextBackspaceDetector)
//        }

Only leave filters = arrayOf(emptyEditTextBackspaceDetector) (line 532) uncommented.

Then follow these steps:

1. start the demo app
2. place the cursor at the beginning, right before the image
3. enter anything
4. observe the exception is thrown but caught by this code correctly

I've tested it and confirmed the crash is captured by the code in this branch and the call to the external logger is correctly made 👍

[jrcacd]

How can we catch the ArrayIndexOutOfBoundsException exception?