false problem reported for "variable assigned but never used"

[mikevaMSFT]

Issue Type: Bug

A "problem" is being reported $errMsg variable is being assigned but never used.
It is assigned inside a Foreach-Object loop and then used to call a .NET method outside the loop.

Example...

$errItem | Foreach-Object {
[string]$errMsg += "'$($PSItem.name)' " + "$($invalidIP) $($PSItem.value)`n"
}
[System.Windows.Forms.MessageBox]::Show($errMsg, $errTitle, [System.Windows.Forms.MessageBoxButtons]::OK)

Extension version: 2020.3.0
VS Code version: Code 1.43.2 (0ba0ca52957102ca3527cf479571617f0de6ed50, 2020-03-24T07:38:38.248Z)
OS version: Windows_NT x64 10.0.18363

System Info

Item	Value
CPUs	Intel(R) Xeon(R) W-2123 CPU @ 3.60GHz (8 x 3600)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on oop_rasterization: disabled_off protected_video_decode: unavailable_off rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off_ok webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	31.73GB (12.69GB free)
Process Argv
Screen Reader	no
VM	0%

[bergmeister]

@mikevaMSFT This is a well known issue of the rule being limited to just one scriptblock scope for its analysis, see related issues of the Area - PSUseDeclaredVarsMoreThanAssignments label. As this issue is an exact duplicate of #1163, I am going to close it.
@dseeni Not sure what you mean, can you expand please?
@rjmholt @SydneyhSmith I think we need to have a line in the issue template of PSSA and vscode-powershell to tell people that false positives of PSUseDeclaredVarsMoreThanAssignments are a known issue.

[dseeni]

@bergmeister My mistake, I think the issue has to do with neovim handlying multi-line messages in the editor output https://github.com/neoclide/coc.nvim/wiki/Language-servers,
unfortunately with this error, in neovim, it will grab focus from the editor and require me to hit enter. Not sure if you can help with that.