Add PSReadLine regression tests

test/powershell/PSReadLine.Tests.ps1

@@ -0,0 +1,32 @@
+Describe "PSReadLine" {
+    BeforeAll {
+        if (Get-Module PSReadLine) {
+            $originalEditMode = (Get-PSReadLineOption).EditMode
+            Remove-Module PSReadLine
+        }
+    }
+
+    It "Should import the module correctly" {
+        Import-Module PSReadLine
+        $module = Get-Module PSReadLine
+        $module.Name | Should Be "PSReadLine"
+        $module.Version | Should Be "1.2"
+    }
+
+    It "Should set the edit mode" {
+        Set-PSReadlineOption -EditMode Windows
+        (Get-PSReadlineKeyHandler | where { $_.Key -eq "Ctrl+A" }).Function | Should Be SelectAll
+
+        Set-PSReadlineOption -EditMode Emacs
+        (Get-PSReadlineKeyHandler | where { $_.Key -eq "Ctrl+A" }).Function | Should Be BeginningOfLine
+    }
+
+    AfterAll {
+        Remove-Module PSReadLine
+
+        if ($originalEditMode) {
+            Import-Module PSReadLine
+            Set-PSReadlineOption -EditMode $originalEditMode
+        }
+    }
+}