VSCode system.typeloadexception

[Big2thaE]

Issue Type: Bug

Start Powershell Integrated Console. Results in: VSCode system.typeloadexception: could not load type 'system.management.automation.subsystem.predictionresult' from assembly.......

Extension version: 2021.2.2
VS Code version: Code 1.56.2 (054a9295330880ed74ceaedda236253b4f39a335, 2021-05-12T17:13:13.157Z)
OS version: Windows_NT x64 10.0.19042

System Info

Item	Value
CPUs	Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz (4 x 2195)
GPU Status	2d_canvas: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: enabled_on video_decode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	7.41GB (2.62GB free)
Process Argv	--crash-reporter-id 6e23fc86-de8f-44cf-ae28-78c663b580ed
Screen Reader	no
VM	0%

A/B Experiments

vsliv368cf:30146710
vsreu685:30147344
python383:30185418
vspyt653:30270858
pythonvspyt602:30300191
vspor879:30202332
vspor708:30202333
vspor363:30204092
pythonvspyt639:30300192
pythontb:30283811
pythonvspyt943cf:30300583
vspre833cf:30267465
pythonptprofiler:30281270
vshan820:30294714
pythondataviewer:30285071
vscus158cf:30286554
vscgsv2ct:30307505
vscorehov:30309549
bridgeflight:30302069
vscod805:30301674

[Big2thaE]

VSCodePSError20210531.mp4

[andyleejordan]

This appears to be a bug relating to an interface change in PowerShell Preview and PSReadLine, and not a VS Code PowerShell extension specific issue. To resolve your issue here, install the stable PowerShell version instead of the preview. See PowerShell/PSReadLine#2511

[andyleejordan]

This is weird...this should not be happening with PSReadLine 2.1.0 based on the PowerShell 7 preview release notes: https://github.com/PowerShell/PowerShell/releases/tag/v7.2.0-preview.6

And we bundle 2.1.0 in the extension, so either it is actually buggy with 2.1.0 or your systems seem to have an incompatible version of PSReadLine installed.

[andyleejordan]

@Big2thaE have you installed a beta version of PSReadLine on your machine?

[andyleejordan]

Also see PowerShell/PowerShell#15496

[andyleejordan]

Ah I found it in the GIF, you do have PSReadLine 2.2.0-beta2 installed. Ok, please revert to 2.1.0 (just uninstall PSReadLine and let the extension use its bundled version instead).