Tab completion doesn't show files whose names differ from others by case only

[dkaszews]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues, especially the pinned issues.

Exception report

N/A

Screenshot

N/A

Environment data

PS Version: 7.3.0-preview.7
PS HostName: ConsoleHost
PSReadLine Version: 2.2.6
PSReadLine EditMode: Vi
OS: Linux Cuddles-Berry 5.15.0-1015-raspi #17-Ubuntu SMP PREEMPT Mon Sep 12 13:14:51 UTC 2022 aarch64 aarch64 aarch64 GNU/Linux
BufferWidth: 208
BufferHeight: 55

Steps to reproduce

Promoted from PowerShell/PowerShell#14365

Non-Windows filesystems are case-sensitive, and there has been an option fsutil.exe file queryCaseSensitiveInfo $path enable to make Windows also case sensitive on per-folder basis (useful for interop, e.g. WSL or checking out repositories with mixed-case files). PSReadLine suggestion deduplication logic uses HashSet<string>(StringComparer.OrdinalIgnoreCase) which is then a problem when you have files differing only in case.

Repro steps:

$tempdir = "tmp:/$(Get-Random)"
New-Item $tempdir Directory
if ($PSVersionTable.OS -match 'Windows') { fsutil.exe file queryCaseSensitiveInfo $tempdir enable }
New-Item 'TEST', 'test'
# input: ./t<TAB><TAB>

Expected behavior

Suggestions cycle between ./test and ./TEST

Actual behavior

Suggestion shows only one option, usually ./TEST because it was created earlier, but may by environment

🎉 This issue was addressed in 3456, which has now been successfully released in v2.3.0-beta0. 🎉