add read-host tests

test/powershell/Modules/Microsoft.PowerShell.Utility/Read-Host.Tests.ps1

@@ -0,0 +1,42 @@
+if ( ! (get-module -ea silentlycontinue TestHostCS ))
+{
+    $root = git rev-parse --show-toplevel
+    $pestertestroot = join-path $root test/powershell
+    $common = join-path $pestertestroot Common
+    $hostmodule = join-path $common TestHostCS.psm1
+    import-module $hostmodule
+}
+Describe "Read-Host Test" -tag "CI" {
+    BeforeAll {
+        $th = New-TestHost
+        $rs = [runspacefactory]::Createrunspace($th)
+        $rs.open()
+        $ps = [powershell]::Create()
+        $ps.Runspace = $rs
+        $ps.Commands.Clear()
+    }
+    AfterEach {
+        $ps.Commands.Clear()
+    }
+    AfterAll {
+        $rs.Close()
+        $rs.Dispose()
+        $ps.Dispose()
+    }
+    It "Read-Host returns expected string" {
+        $result = $ps.AddCommand("Read-Host").Invoke()
+        $result | Should Be $th.UI.ReadLineData
+    }
+    It "Read-Host sets the prompt correctly" {
+        $result = $ps.AddScript("Read-Host -prompt myprompt").Invoke()
+        $prompt = $th.ui.streams.prompt[0]
+        $prompt | should Not BeNullOrEmpty
+        $prompt.split(":")[-1] | should be myprompt
+    }
+    It "Read-Host returns a secure string when using -AsSecureString parameter" {
+        $result = $ps.AddScript("Read-Host -AsSecureString").Invoke() | select-object -first 1
+        $result.GetType().Name | should be "SecureString"
+        [pscredential]::New("foo",$result).GetNEtworkCredential().Password | should BeExactly TEST
+
+    }
+}