Nested errors in debugging not shown in console

[ili101]

Issue Type: Bug

Example from https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_trap?view=powershell-7#using-the-break-and-continue-keywords

function break_example {
    trap {
        "Error trapped"
        break
    }
    1/$null
    "Function completed."
}

break_example

1. Save example to file (Optional).
2. Run with F5.

Expected output (and is working correctly on 2020.2.0):
Error trapped + Error

Actual output on 2020.3.0:
No error shown

Extension version: 2020.3.0
Tested on PS7 and 5.1
VS Code version: Code 1.42.1 (c47d83b293181d9be64f27ff093689e8e7aed054, 2020-02-11T14:45:59.656Z)
OS version: Windows_NT x64 10.0.17763

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz (2 x 3392)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: disabled_off oop_rasterization: disabled_off protected_video_decode: unavailable_off rasterization: unavailable_off skia_renderer: disabled_off surface_control: disabled_off surface_synchronization: enabled_on video_decode: enabled viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	2.00GB (0.22GB free)
Process Argv
Screen Reader	no
VM	100%

[TylerLeonhardt]

I can repro this on macOS as well...

It only seems to have started occurring in the last update as it doesn't repro in the PowerShell Preview extension

[rjmholt]

Started looking into this, and there's definitely a race condition at work here; in some debugging sessions, choosing the right breakpoints actually gets the errors to print.

We correctly catch the RuntimeException and process it here.

That fires off an Out-Default execution without awaiting it.

When errors are written as expected, they go through this method in our host implementation, but this isn't reliably called...