[Windows] Implement new directories hierarchy (#8616)

images/windows/scripts/tests/MSYS2.Tests.ps1

@@ -0,0 +1,72 @@
+BeforeAll {
+    $msys2Dir = "C:\msys64\usr\bin"
+    $originalPath = $env:PATH
+}
+
+Describe "MSYS2 packages" {
+    BeforeEach {
+        $env:PATH = "$msys2Dir;$env:PATH"
+    }
+
+    It "msys2Dir exists" {
+        $msys2Dir | Should -Exist
+    }
+
+    $TestCases = @(
+        @{ ToolName = "bash.exe" }
+    )
+
+    if (Test-IsWin19) {
+        $TestCases += @(
+            @{ ToolName = "tar.exe" }
+            @{ ToolName = "make.exe" }
+        )
+    }
+
+    It "<ToolName> is installed in <msys2Dir>" -TestCases $TestCases {
+        (Get-Command "$ToolName").Source | Should -BeLike "$msys2Dir*"
+    }
+
+    It "<ToolName> is avaialable" -TestCases $TestCases {
+        "$ToolName" | Should -ReturnZeroExitCodeWithParam
+    }
+
+    AfterEach {
+        $env:PATH = $originalPath
+    }
+}
+
+$mingwTypes = (Get-ToolsetContent).MsysPackages.mingw
+foreach ($mingwType in $mingwTypes) {
+    Describe "$($mingwType.arch) packages" {
+        $tools = $mingwType.runtime_packages
+        $execDir = Join-Path "C:\msys64" $mingwType.exec_dir | Join-Path -ChildPath "bin"
+        
+        foreach ($tool in $tools) {
+            Context "$($tool.name) package"{
+                $executables = $tool.executables | ForEach-Object {
+                    @{
+                        ExecName = $_
+                        ExecDir = $execDir
+                    }
+                }
+
+                BeforeEach {
+                    $env:PATH = "$execDir;$env:PATH"
+                }
+
+                It "<ExecName> is installed in <ExecDir>" -TestCases $executables {
+                    (Get-Command "$ExecName").Source | Should -BeLike "$ExecDir*"
+                }
+
+                It "<ExecName> is available" -TestCases $executables {
+                    "$ExecName" | Should -ReturnZeroExitCodeWithParam
+                }
+
+                AfterEach {
+                    $env:PATH = $originalPath
+                }
+            }
+        }
+    }
+}