Add tests for ProxyCommand APIs to improve coverage (#4791)

Examine the code in ProxyCommand.cs to find out specific missing areas.

Author: daxian-dbw

test/powershell/engine/Api/ProxyCommand.Tests.ps1

@@ -0,0 +1,162 @@
+using namespace System.Management.Automation
+using namespace System.Collections.ObjectModel
+
+Describe 'ProxyCommand Tests' -Tags "CI" {
+    BeforeAll {
+        function GetSectionText {
+            param ($object)
+            $texts = $object | Out-String -Stream | ForEach-Object {
+                if (![string]::IsNullOrWhiteSpace($_)) { $_.Trim() }
+            }
+            $texts -join ""
+        }
+
+        function ProxyTest {
+            [CmdletBinding(DefaultParameterSetName='Name')]
+            param (
+                [Parameter(ParameterSetName="Name", Mandatory=$true)]
+                [ValidateSet("Orange", "Apple")]
+                [string] $Name,
+
+                [Parameter(ParameterSetName="Id", Mandatory=$true)]
+                [ValidateRange(1,5)]
+                [int] $Id,
+
+                [Parameter(ValueFromPipeline)]
+                [string] $Message
+            )
+
+            DynamicParam {
+                $ParamAttrib  = [parameter]::new()
+                $ParamAttrib.Mandatory  = $true
+
+                $AttribColl = [Collection[System.Attribute]]::new()
+                $AttribColl.Add($ParamAttrib)
+
+                $RuntimeParam  = [RuntimeDefinedParameter]::new('LastName', [string], $AttribColl)
+                $RuntimeParamDic  = [RuntimeDefinedParameterDictionary]::new()
+                $RuntimeParamDic.Add('LastName',  $RuntimeParam)
+                return  $RuntimeParamDic
+            }
+
+            Begin {
+                $AllMessages = @()
+                if ($PSCmdlet.ParameterSetName -eq "Name") {
+                    $MyString = $Name, $PSBoundParameters['LastName'] -join ","
+                } else {
+                    $MyString = $Id, $PSBoundParameters['LastName'] -join ","
+                }
+            }
+
+            Process {
+                if ($Message) {
+                    $AllMessages += $Message
+                }
+            }
+
+            End {
+                $MyString + " - " + ($AllMessages -join ";")
+            }
+        }
+    }
+
+    It "Test ProxyCommand.GetHelpComments" {
+        $helpObj = Get-Help Get-Alias -Full
+        $helpContent = [System.Management.Automation.ProxyCommand]::GetHelpComments($helpObj)
+
+        $funcBody = @"
+    <#
+    {0}
+    #>
+
+    param({1})
+"@
+        $params = $helpObj.parameters.parameter
+        $paramString = '${0}' -f $params[0].name
+        for ($i = 1; $i -lt $params.Length; $i++) {
+            $paramString += ',${0}' -f $params[$i].name
+        }
+
+        $bodyToUse = $funcBody -f $helpContent, $paramString
+        $bodySB = [scriptblock]::Create($bodyToUse)
+        Set-Item -Path function:\TestHelpComment -Value $bodySB
+        $newHelpObj = Get-Help TestHelpComment -Full
+
+        $helpObj.Synopsis | Should Be $newHelpObj.Synopsis
+        $oldDespText = GetSectionText $helpObj.description
+        $newDespText = GetSectionText $newHelpObj.description
+        $oldDespText | Should Be $newDespText
+
+        $oldParameters = @($helpObj.parameters.parameter)
+        $newParameters = @($newHelpObj.parameters.parameter)
+        $oldParameters.Length | Should Be $newParameters.Length
+        $oldParameters.name -join "," | Should Be ($newParameters.name -join ",")
+
+        $oldExamples = @($helpObj.examples.example)
+        $newExamples = @($newHelpObj.examples.example)
+        $oldExamples.Length | Should Be $newExamples.Length
+    }
+
+    It "Test generate proxy command" {
+        $cmdInfo = Get-Command -Name Get-Content
+        $cmdMetadata = [CommandMetadata]::new($cmdInfo)
+        $proxyBody = [ProxyCommand]::Create($cmdMetadata, "--DummyHelpContent--")
+        $proxyBody | Should Match '--DummyHelpContent--'
+
+        $proxyBodySB = [scriptblock]::Create($proxyBody)
+        Set-Item -Path function:\MyGetContent -Value $proxyBodySB
+
+        $expectedContent = "Hello World"
+        Set-Content -Path $TestDrive\content.txt -Value $expectedContent -Encoding Unicode
+        $myContent = MyGetContent -Path $TestDrive\content.txt -Encoding Unicode
+        $myContent | Should Be $expectedContent
+    }
+
+    It "Test generate individual components" {
+        $cmdInfo = Get-Command -Name ProxyTest
+        $cmdMetadata = [CommandMetadata]::new($cmdInfo)
+        $template = @"
+{0}
+param(
+{1}
+)
+
+DynamicParam {{
+{2}
+}}
+
+Begin {{
+{3}
+}}
+
+Process {{
+{4}
+}}
+
+End {{
+{5}
+}}
+"@
+
+        $cmdletBindig = [ProxyCommand]::GetCmdletBindingAttribute($cmdMetadata)
+        $params = [ProxyCommand]::GetParamBlock($cmdMetadata)
+        $dynamicParams = [ProxyCommand]::GetDynamicParam($cmdMetadata)
+        $begin = [ProxyCommand]::GetBegin($cmdMetadata)
+        $process = [ProxyCommand]::GetProcess($cmdMetadata)
+        $end = [ProxyCommand]::GetEnd($cmdMetadata)
+
+        $funcBody = $template -f $cmdletBindig, $params, $dynamicParams, $begin, $process, $end
+        $bodySB = [scriptblock]::Create($funcBody)
+        Set-Item -Path function:\MyProxyTest -Value $bodySB
+
+        $cmdMyProxyTest = Get-Command MyProxyTest
+        $dyParam = $cmdMyProxyTest.Parameters.GetEnumerator() | Where-Object { $_.Value.IsDynamic }
+        $dyParam.Key | Should Be 'LastName'
+
+        $result = "Msg1", "Msg2" | MyProxyTest -Name Apple -LastName Last
+        $result | Should Be "Apple,Last - Msg1;Msg2"
+
+        $result = "Msg1", "Msg2" | MyProxyTest -Id 3 -LastName Last
+        $result | Should Be "3,Last - Msg1;Msg2"
+    }
+}