ValidateScriptBlock: Adding -AstCondition, -ExcludeType, -IncludeType (Fixes #225, Fixes #226)

Author: James Brundage

Transpilers/Parameters/ValidateScriptBlock.psx.ps1

@@ -57,6 +57,48 @@ $NoBlock,
 [switch]
 $NoParameter,
 
+# If set, will ensure that the script block contains types in this list.
+# Passing -IncludeType without -ExcludeType will make -ExcludeType default to *.
+[ValidateScript({
+$validTypeList = [System.String],[System.String[]],[System.Text.RegularExpressions.Regex],[System.Type],[System.Type[]]
+$thisType = $_.GetType()
+$IsTypeOk =
+    $(@( foreach ($validType in $validTypeList) {
+        if ($_ -as $validType) {
+            $true;break
+        }
+    }))
+if (-not $isTypeOk) {
+    throw "Unexpected type '$(@($thisType)[0])'.  Must be 'string','string[]','regex','type','type[]'."
+}
+return $true
+})]
+$IncludeType,
+
+# If set, will ensure that the script block does not use the types in this list.
+# Passing -IncludeType without -ExcludeType will make -ExcludeType default to *.
+[ValidateScript({
+$validTypeList = [System.String],[System.String[]],[System.Text.RegularExpressions.Regex],[System.Type],[System.Type[]]
+$thisType = $_.GetType()
+$IsTypeOk =
+    $(@( foreach ($validType in $validTypeList) {
+        if ($_ -as $validType) {
+            $true;break
+        }
+    }))
+if (-not $isTypeOk) {
+    throw "Unexpected type '$(@($thisType)[0])'.  Must be 'string','string[]','regex','type','type[]'."
+}
+return $true
+})]
+$ExcludeType,
+
+# One or more AST conditions to validate.
+# If no results are found or the condition throws, the script block will be considered invalid.
+[Alias('AstConditions', 'IfAst')]
+[Scriptblock[]]
+$AstCondition,
+
 # A VariableExpression.  If provided, the Validation attributes will apply to this variable.
 [Parameter(Mandatory,ValueFromPipeline,ParameterSetName='VariableExpressionAST')]
 [Management.Automation.Language.VariableExpressionAST]
@@ -118,7 +160,123 @@ $validateScripts = @(
     return $true    
 })]
 '@
-    }    
+    }
+
+    # If -IncludeType or -ExcludeType were provided
+    if ($IncludeType -or $ExcludeType) {        
+        if (-not $ExcludeType) {
+            $ExcludeType = '*'
+        }
+        
+        if (-not $IncludeType -and $ExcludeType -eq '*') {
+            $AstCondition += {
+param($ast)
+if ($ast -is [Management.Automation.Language.TypeExpressionAst]) {
+    throw "AST cannot contain types"
+}
+return $true}
+        }
+        else {
+            $AstCondition += [ScriptBlock]::Create(@"
+param(`$ast)
+`$included = $(
+    if (-not $IncludeType) { '$null' }
+    @($(foreach ($incT in $IncludeType) {
+    if ($incT -is [string]) {
+        "'$($incT -replace "'","''")'"
+    }
+    elseif ($incT -is [type]) {
+        "[$($incT.FullName -replace '^System\.')]"
+    }
+    elseif ($incT -is [regex]) {
+        "[Regex]::new('$($incT.ToString().Replace("'","''"))','$($incT.Options)','$($incT.MatchTimeout)')"
+    }
+})) -join ',')
+`$excluded = $(@(
+    if (-not $ExcludeType) { '$null' }
+    $(foreach ($excT in $ExcludeType) {
+    if ($excT -is [string]) {
+        "'$($excT -replace "'","''")'"
+    }
+    elseif ($excT -is [type]) {
+        "[$($excT.FullName -replace '^System\.')]"
+    }
+    elseif ($excT -is [regex]) {
+        "[Regex]::new('$($excT.ToString().Replace("'","''"))','$($excT.Options)','$($excT.MatchTimeout)')"
+    }
+})) -join ',')
+if (`$ast -is [Management.Automation.Language.TypeExpressionAst]) {
+$(if ($IncludeType) {
+{
+    foreach ($inc in $included) {
+        if ($inc -is [string] -and $ast.TypeName -like $inc) {
+            return $true
+        }
+        elseif ($inc -is [Regex] -and $ast.TypeName -match $inc) {
+            return $true
+        }
+        elseif ($inc -is [type]){
+            $reflectionType = $ast.TypeName.GetReflectionType()
+            if ($inc -eq $reflectionType) { return $true}
+            if ($inc.IsSubclassOf($reflectionType) -or $reflectionType.IsSubclassOf($inc)) {
+                return $true
+            }
+            if ($inc.IsInterface -and $reflectionType.getInterFace($inc)) {
+                return $true
+            }
+            if ($reflectionType.IsInterface -and $inc.getInterFace($reflectionType)) {
+                return $true
+            }            
+        }
+    }
+}})
+$({
+    $throwMessage = "[$($ast.Typename)] is not allowed" 
+    foreach ($exc in $excluded) {
+        if ($exc -is [string] -and $ast.TypeName -like $exc) {
+            throw $throwMessage
+        }
+        elseif ($exc -is [regex] -and $ast.TypeName -match $exc) {
+            throw $throwMessage
+        }
+        elseif ($exc -is [type]) {
+            $reflectionType = $ast.TypeName.GetReflectionType()
+            if ($ecx -eq $reflectionType) { 
+                throw $throwMessage
+            }
+            elseif ($exc.IsSubclassOf($reflectionType) -or $reflectionType.IsSubclassOf($exc)) {
+                throw $throwMessage
+            }
+            elseif ($exc.IsInterface -and $reflectionType.getInterFace($exc)) {
+                throw $throwMessage
+            }
+            elseif ($reflectionType.IsInterface -and $exc.getInterFace($reflectionType)) {
+                throw $throwMessage
+            }            
+        }
+    }
+})
+
+}
+return `$true
+"@)
+        }
+    }
+    
+    if ($AstCondition) {
+@"
+[ValidateScript({
+    if (`$_ -isnot [ScriptBlock]) { return `$true }    
+    `$astConditions = {$($AstCondition -join '} , {')}
+    `$scriptBlockAst = `$_.Ast
+    foreach (`$astCondition in `$astConditions) {
+        `$foundResults = `$scriptBlockAst.FindAll(`$astCondition, `$true)
+        if (-not `$foundResults) { return `$false}
+    }
+    return `$true    
+})]
+"@
+    }
 )
     if (-not $validateScripts) { return }