Adding ValidateTypes (50)

Author: James Brundage

Transpilers/Parameters/ValidateTypes.psx.ps1

@@ -0,0 +1,96 @@
+<#
+.Synopsis
+    Validates if an object is one or more types.
+.Description
+    Validates if an object is one or more types.  
+    
+    This allows for a single parameter to handle multiple potential types.
+.Example
+    {
+        param(
+        [ValidateTypes(TypeName="ScriptBlock","string")]
+        $In
+        )
+    } | .>PipeScript
+.Example
+    {"hello world"} |
+        Invoke-PipeScript -ScriptBlock {
+            param(
+            [vfp()]
+            [ValidateTypes(TypeName="ScriptBlock","string")]            
+            $In
+            )
+
+            $In
+        }
+.Example
+    1 | 
+        Invoke-PipeScript -ScriptBlock {
+            param(
+            [vfp()]
+            [ValidateTypes(TypeName="ScriptBlock","string")]            
+            $In
+            )
+
+            $In
+        }
+#>
+[CmdletBinding(DefaultParameterSetName='Parameter')]
+param(
+# The name of one or more types.
+# Types can either be a .NET types of .PSTypenames
+# TypeNames will be treated first as real types, then as exact matches, then as wildcards, and then as regular expressions.
+[Parameter(Mandatory,Position=0)]
+[string[]]
+$TypeName
+)
+
+
+$checkTypes = @"
+`$validTypeList = '$($typeName -join "','")'
+"@ + {
+$thisType = @(
+    if ($_.GetType) {
+        $_.GetType()
+    }
+    $_.PSTypenames
+)
+$IsTypeOk = 
+    $(@(foreach ($validTypeName in $validTypeList) {
+        $realType = $validTypeName -as [type]
+        foreach ($Type in $thisType) {
+            if ($Type -is [type]) {
+                if ($realType) {
+                    $realType -eq $type -or
+                    $type.IsSubClassOf($realType) -or
+                    ($realType.IsInterface -and $type.GetInterface($realType))
+                } else {
+                    $type.Name -eq $realType -or 
+                    $type.Fullname -eq $realType -or 
+                    $type.Fullname -like $realType -or $(
+                        ($realType -as [regex]) -and 
+                        $type.Name -match $realType -or $type.Fullname -match $realType
+                    )
+                }
+            } else {
+                $type -eq $realType -or 
+                $type -like $realType -or (
+                    ($realType -as [regex]) -and 
+                    $type -match $realType
+                )
+            }
+        }
+    }) -eq $true) -as [bool]
+}
+
+if ($PSCmdlet.ParameterSetName -eq 'Parameter') {
+[scriptblock]::Create(@"
+[ValidateScript({
+$checkTypes
+if (-not `$isTypeOk) {
+    throw "Unexpected type '`$(@(`$thisType)[0])'.  Must be '$($typeName -join "','")'."
+}
+})]
+param()
+"@)
+}