PowerShell · adityapatwardhan · Mar 11, 2019 · Feb 28, 2019 · Feb 28, 2019 · Feb 28, 2019
diff --git a/docs/learning-powershell/create-powershell-scripts.md b/docs/learning-powershell/create-powershell-scripts.md
@@ -62,4 +62,4 @@ else
 $IP | Where-Object {$_ -ne '127.0.0.1'}
 ```
 
-[run-ps]:https://windowsitpro.com/powershell/running-powershell-scripts-easy-1-2-3
+[run-ps]:https://www.itprotoday.com/powershell/running-powershell-scripts-easy-1-2-3
diff --git a/docs/learning-powershell/powershell-beginners-guide.md b/docs/learning-powershell/powershell-beginners-guide.md
@@ -334,7 +334,7 @@ For more details, see [Create and Run PowerShell Script Guide][create-run-script
 [create-ps-module]:https://www.business.com/articles/powershell-modules/
 [remoting]:https://channel9.msdn.com/Series/GetStartedPowerShell3/06
 [in-depth]: https://channel9.msdn.com/events/MMS/2012/SV-B406
-[remote-mgmt]:https://windowsitpro.com/powershell/powershell-basics-remote-management
+[remote-mgmt]:https://www.itprotoday.com/powershell/powershell-basics-remote-management
 [remote-commands]:https://docs.microsoft.com/powershell/scripting/core-powershell/running-remote-commands?view=powershell-6
 [examples]:https://examples.oreilly.com/9780596528492/
 [examples-ps-module]:https://msdn.microsoft.com/library/dd878340%28v=vs.85%29.aspx

diff --git a/test/powershell/Host/ConsoleHost.Tests.ps1 b/test/powershell/Host/ConsoleHost.Tests.ps1
@@ -119,6 +119,7 @@ Describe "ConsoleHost unit tests" -tags "Feature" {
             { & $powershell -input blah -comm { $input } } | Should -Throw -ErrorId "IncorrectValueForFormatParameter"
         }
     }
+
     Context "CommandLine" {
         It "simple -args" {
             & $powershell -noprofile { $args[0] } -args "hello world" | Should -Be "hello world"
@@ -611,6 +612,26 @@ foo
             }
         }
     }
+
+    Context "CustomPipeName startup tests" {
+
+        It "Should create pipe file if CustomPipeName is specified" {
+            $pipeName = [System.IO.Path]::GetRandomFileName()
+            $pipePath = Get-PipePath $pipeName
+
+            # The pipePath should be created by the time the -Command is executed.
+            & $powershell -CustomPipeName $pipeName -Command "Test-Path '$pipePath'" | Should -BeTrue
+        }
+
+        It "Should throw if CustomPipeName is too long on Linux or macOS" -Skip:($IsWindows) {
+            # Generate a string that is larger than the max pipe name length.
+            $longPipeName = [string]::new("A", 200)
+
+            "`$pid" | & $powershell -CustomPipeName $longPipeName -c -
+            # 64 is the ExitCode for BadCommandLineParameter
+            $LASTEXITCODE | Should -Be 64
+        }
+    }
 }
 
 Describe "WindowStyle argument" -Tag Feature {

diff --git a/test/powershell/Modules/Microsoft.PowerShell.Core/Enter-PSHostProcess.Tests.ps1 b/test/powershell/Modules/Microsoft.PowerShell.Core/Enter-PSHostProcess.Tests.ps1
@@ -1,134 +1,181 @@
 # Copyright (c) Microsoft Corporation. All rights reserved.
 # Licensed under the MIT License.
 
+$powershell = Join-Path -Path $PsHome -ChildPath "pwsh"
+
+function Wait-JobPid {
+    param (
+        $Job
+    )
+
+    # This is to prevent hanging in the test.
+    $startTime = [DateTime]::Now
+    $TimeoutInMilliseconds = 10000
+
+    # This will receive the pid of the Job process and nothing more since that was the only thing written to the pipeline.
+    do {
+        Start-Sleep -Seconds 1
+        $pwshId = Receive-Job $Job
+
+        if (([DateTime]::Now - $startTime).TotalMilliseconds -gt $timeoutInMilliseconds) {
+            throw "Unable to receive PowerShell process id."
+        }
+    } while (!$pwshId)
+
+    $pwshId
+}
+
+# Executes the Enter/Exit PSHostProcess script that returns the pid of the process that's started.
+function Invoke-PSHostProcessScript {
+    param (
+        [string] $ArgumentString,
+        [int] $Id,
+        [int] $Retry = 5 # Default retry of 5 times
+    )
+
+    $sb = {
+        # use $i as an incrementally growing pause based on the attempt number
+        # so that it's more likely to succeed.
+        $commandStr = @'
+Start-Sleep -Seconds {0}
+Enter-PSHostProcess {1} -ErrorAction Stop
+$pid
+Exit-PSHostProcess
+'@ -f $i, $ArgumentString
+
+        ($commandStr | & $powershell -c -) -eq $Id
+    }
+
+    $result = $false
+    $failures = 0
+    foreach ($i in 1..$Retry) {
+        if ($sb.Invoke()) {
+            $result = $true
+            break
+        }
+
+        $failures++
+    }
+
+    if($failures) {
+        Write-Warning "Enter-PSHostProcess script failed $i out of $Retry times."
+    }
+
+    $result
+}
+
 Describe "Enter-PSHostProcess tests" -Tag Feature {
     Context "By Process Id" {
-        BeforeAll {
-            $params = @{
-                FilePath = "pwsh"
-                PassThru = $true
-                RedirectStandardOutput = "TestDrive:\pwsh_out.log"
-                RedirectStandardError = "TestDrive:\pwsh_err.log"
-            }
-            $pwsh = Start-Process @params
-
-            if ($IsWindows) {
-                $params = @{
-                    FilePath = "powershell"
-                    PassThru = $true
-                    RedirectStandardOutput = "TestDrive:\powershell_out.log"
-                    RedirectStandardError = "TestDrive:\powershell_err.log"
+
+        BeforeEach {
+            # Start a normal job where the first thing it does is return $pid. After that, spin forever.
+            # We will use this job as the target process for Enter-PSHostProcess
+            $pwshJob = Start-Job {
+                $pid
+                while ($true) {
+                    Start-Sleep -Seconds 30 | Out-Null
                 }
-                $powershell = Start-Process @params
             }
 
+            $pwshId = Wait-JobPid $pwshJob
         }
 
-        AfterAll {
-            $pwsh | Stop-Process
-
-            if ($IsWindows) {
-                $powershell | Stop-Process
-            }
+        AfterEach {
+            $pwshJob | Stop-Job -PassThru | Remove-Job
         }
 
-        It "Can enter and exit another PSHost" -Pending:$true {
-            Wait-UntilTrue { (Get-PSHostProcessInfo -Id $pwsh.Id) -ne $null }
+        It "Can enter, exit, and re-enter another PSHost" {
+            Wait-UntilTrue { [bool](Get-PSHostProcessInfo -Id $pwshId) }
 
-            "Enter-PSHostProcess -Id $($pwsh.Id) -ErrorAction Stop
-            `$pid
-            Exit-PSHostProcess" | pwsh -c - | Should -Be $pwsh.Id
+            # This will enter and exit another process
+            Invoke-PSHostProcessScript -ArgumentString "-Id $pwshId" -Id $pwshId |
+                Should -BeTrue -Because "The script was able to enter another process and grab the pid of '$pwshId'."
+
+            # Re-enter and exit the other process
+            Invoke-PSHostProcessScript -ArgumentString "-Id $pwshId" -Id $pwshId |
+                Should -BeTrue -Because "The script was able to re-enter another process and grab the pid of '$pwshId'."
         }
 
-        It "Can enter and exit another Windows PowerShell PSHost" -Skip:(!$IsWindows) {
-            Wait-UntilTrue { (Get-PSHostProcessInfo -Id $powershell.Id) -ne $null }
+        It "Can enter, exit, and re-enter another Windows PowerShell PSHost" -Skip:(!$IsWindows) {
+            # Start a Windows PowerShell job where the first thing it does is return $pid. After that, spin forever.
+            # We will use this job as the target process for Enter-PSHostProcess
+            $powershellJob = Start-Job -PSVersion 5.1 {
+                $pid
+                while ($true) {
+                    Start-Sleep -Seconds 30 | Out-Null
+                }
+            }
 
-            "Enter-PSHostProcess -Id $($powershell.Id) -ErrorAction Stop
-            `$pid
-            Exit-PSHostProcess" | pwsh -c - | Should -Be $powershell.Id
+            $powershellId = Wait-JobPid $powershellJob
+
+            try {
+                Wait-UntilTrue { [bool](Get-PSHostProcessInfo -Id $powershellId) }
+
+                # This will enter and exit another process
+                Invoke-PSHostProcessScript -ArgumentString "-Id $powershellId" -Id $powershellId |
+                    Should -BeTrue -Because "The script was able to enter another process and grab the pid of '$powershellId'."
+
+                # Re-enter and exit the other process
+                Invoke-PSHostProcessScript -ArgumentString "-Id $powershellId" -Id $powershellId |
+                    Should -BeTrue -Because "The script was able to re-enter another process and grab the pid of '$powershellId'."
+
+            } finally {
+                $powershellJob | Stop-Job -PassThru | Remove-Job
+            }
         }
 
-        It "Can enter using NamedPipeConnectionInfo" -Pending:$true {
+        It "Can enter using NamedPipeConnectionInfo" {
             try {
-                $npInfo = [System.Management.Automation.Runspaces.NamedPipeConnectionInfo]::new($pwsh.Id)
+                Wait-UntilTrue { [bool](Get-PSHostProcessInfo -Id $pwshId) }
+
+                $npInfo = [System.Management.Automation.Runspaces.NamedPipeConnectionInfo]::new($pwshId)
                 $rs = [runspacefactory]::CreateRunspace($npInfo)
                 $rs.Open()
                 $ps = [powershell]::Create()
                 $ps.Runspace = $rs
-                $ps.AddScript('$pid').Invoke() | Should -Be $pwsh.Id
+                $ps.AddScript('$pid').Invoke() | Should -Be $pwshId
             } finally {
                 $rs.Dispose()
+                $ps.Dispose()
             }
         }
     }
 
     Context "By CustomPipeName" {
-        BeforeAll {
-            # Helper function to get the correct path for the named pipe.
-            function Get-PipePath {
-                param (
-                    $PipeName
-                )
-                if ($IsWindows) {
-                    return "\\.\pipe\$PipeName"
-                }
-                "$([System.IO.Path]::GetTempPath())CoreFxPipe_$PipeName"
-            }
 
+        It "Can enter, exit, and re-enter using CustomPipeName" {
             $pipeName = [System.IO.Path]::GetRandomFileName()
-            $params = @{
-                FilePath = "pwsh"
-                ArgumentList = @("-CustomPipeName",$pipeName)
-                PassThru = $true
-                RedirectStandardOutput = "TestDrive:\pwsh_out.log"
-                RedirectStandardError = "TestDrive:\pwsh_err.log"
-            }
-            $pwsh = Start-Process @params
-
             $pipePath = Get-PipePath -PipeName $pipeName
-        }
 
-        AfterAll {
-            $pwsh | Stop-Process
-        }
+            # Start a job where the first thing it does is set the custom pipe name, then return $pid.
+            # After that, spin forever.
+            # We will use this job as the target process for Enter-PSHostProcess
+            $pwshJob = Start-Job -ArgumentList $pipeName {
+                [System.Management.Automation.Remoting.RemoteSessionNamedPipeServer]::CreateCustomNamedPipeServer($args[0])
+                $pid
+                while ($true) { Start-Sleep -Seconds 30 | Out-Null }
+            }
 
-        It "Can enter using CustomPipeName" -Pending:$true {
-            Wait-UntilTrue { Test-Path $pipePath }
+            $pwshId = Wait-JobPid $pwshJob
 
-            "Enter-PSHostProcess -CustomPipeName $pipeName -ErrorAction Stop
-            `$pid
-            Exit-PSHostProcess" | pwsh -c - | Should -Be $pwsh.Id
-        }
+            try {
+                Wait-UntilTrue { Test-Path $pipePath }
 
-        It "Can enter, exit, and re-enter using CustomPipeName" -Pending:$true {
-            Wait-UntilTrue { Test-Path $pipePath }
+                # This will enter and exit another process
+                Invoke-PSHostProcessScript -ArgumentString "-CustomPipeName $pipeName" -Id $pwshId |
+                    Should -BeTrue -Because "The script was able to enter another process and grab the pipe of '$pipeName'."
 
-            "Enter-PSHostProcess -CustomPipeName $pipeName -ErrorAction Stop
-            `$pid
-            Exit-PSHostProcess" | pwsh -c - | Should -Be $pwsh.Id
+                # Re-enter and exit the other process
+                Invoke-PSHostProcessScript -ArgumentString "-CustomPipeName $pipeName" -Id $pwshId |
+                    Should -BeTrue -Because "The script was able to re-enter another process and grab the pipe of '$pipeName'."
 
-            "Enter-PSHostProcess -CustomPipeName $pipeName -ErrorAction Stop
-            `$pid
-            Exit-PSHostProcess" | pwsh -c - | Should -Be $pwsh.Id
+            } finally {
+                $pwshJob | Stop-Job -PassThru | Remove-Job
+            }
         }
 
         It "Should throw if CustomPipeName does not exist" {
-            Wait-UntilTrue { Test-Path $pipePath }
-
             { Enter-PSHostProcess -CustomPipeName badpipename } | Should -Throw -ExpectedMessage "No named pipe was found with CustomPipeName: badpipename."
         }
-
-        It "Should throw if CustomPipeName is too long on Linux or macOS" {
-            $longPipeName = "DoggoipsumwaggywagssmolborkingdoggowithalongsnootforpatsdoingmeafrightenporgoYapperporgolongwatershoobcloudsbigolpupperlengthboy"
-
-            if (!$IsWindows) {
-                "`$pid" | pwsh -CustomPipeName $longPipeName -c -
-                # 64 is the ExitCode for BadCommandLineParameter
-                $LASTEXITCODE | Should -Be 64
-            } else {
-                "`$pid" | pwsh -CustomPipeName $longPipeName -c -
-                $LASTEXITCODE | Should -Be 0
-            }
-        }
     }
 }
@@ -16,6 +16,6 @@ Copyright = 'Copyright (c) Microsoft Corporation. All rights reserved.'
 
 Description = 'Temporary module for remoting tests'
 
-FunctionsToExport = 'New-RemoteRunspace', 'New-RemoteSession', 'Enter-RemoteSession', 'Invoke-RemoteCommand', 'Connect-RemoteSession', 'New-RemoteRunspacePool'
+FunctionsToExport = 'New-RemoteRunspace', 'New-RemoteSession', 'Enter-RemoteSession', 'Invoke-RemoteCommand', 'Connect-RemoteSession', 'New-RemoteRunspacePool', 'Get-PipePath'
 
 }
@@ -248,3 +248,13 @@ function Connect-RemoteSession
     $parameters = CreateParameters -ComputerName $ComputerName -Name $Name -Session $Session -ConfigurationName $ConfigurationName
     Connect-PSSession @parameters
 }
+
+function Get-PipePath {
+    param (
+        $PipeName
+    )
+    if ($IsWindows) {
+        return "\\.\pipe\$PipeName"
+    }
+    "$([System.IO.Path]::GetTempPath())CoreFxPipe_$PipeName"
+}