Fix mocks with enum-parameters and ValidateRange (#2191)

* fix mocking for enum-param with validaterange * update test to fix multiple parameters * rename function and fix test * improve test * cleanup * add cmdlet test on windows * add support for untyped parameters * cleanup * fix test * fix ValidateRangeKind test
pester · Jun 30, 2022 · dd7d09e · dd7d09e
1 parent ed6135b
commit dd7d09e
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diff --git a/src/functions/Mock.ps1 b/src/functions/Mock.ps1
@@ -92,6 +92,7 @@ function Create-MockHook ($contextInfo, $InvokeMockCallback) {
 
         $metadata = Repair-ConflictingParameters -Metadata $metadata -RemoveParameterType $RemoveParameterType -RemoveParameterValidation $RemoveParameterValidation
         $paramBlock = [Management.Automation.ProxyCommand]::GetParamBlock($metadata)
+        $paramBlock = Repair-EnumParameters -ParamBlock $paramBlock -Metadata $metadata
 
         if ($contextInfo.Command.CommandType -eq 'Cmdlet') {
             $dynamicParamBlock = "dynamicparam { & `$MyInvocation.MyCommand.Mock.Get_MockDynamicParameter -CmdletName '$($contextInfo.Command.Name)' -Parameters `$PSBoundParameters }"
@@ -1805,3 +1806,55 @@ function New-BlockWithoutParameterAliases {
         $PSCmdlet.ThrowTerminatingError($_)
     }
 }
+
+function Repair-EnumParameters {
+    param (
+        [string]
+        $ParamBlock,
+        [System.Management.Automation.CommandMetadata]
+        $Metadata
+    )
+
+    # proxycommand breaks ValidateRange for enum-parameters
+    # broken arguments (unquoted strings) will show as NamedArguments in ast, while valid arguments are PositionalArguments.
+    # https://github.com/pester/Pester/issues/1496
+    # https://github.com/PowerShell/PowerShell/issues/17546
+    $ast = [System.Management.Automation.Language.Parser]::ParseInput("param($ParamBlock)", [ref]$null, [ref]$null)
+    $brokenValidateRange = $ast.FindAll({
+        param($node)
+        $node -is [System.Management.Automation.Language.AttributeAst] -and
+        $node.TypeName.Name -match '(?:ValidateRange|System\.Management\.Automation\.ValidateRangeAttribute)$' -and
+        $node.NamedArguments.Count -gt 0 -and
+        # triple checking for broken argument - it won't have a value/expression
+        $node.NamedArguments.ExpressionOmitted -notcontains $false
+    }, $false)
+
+    if ($brokenValidateRange.Count -eq 0) {
+        # No errors found. Return original string
+        return $ParamBlock
+    }
+
+    $sb = & $SafeCommands['New-Object'] System.Text.StringBuilder($ParamBlock)
+
+    foreach ($attr in $brokenValidateRange) {
+        $paramName = $attr.Parent.Name.VariablePath.UserPath
+        $originalAttribute = $Metadata.Parameters[$paramName].Attributes | & $SafeCommands['Where-Object'] { $_ -is [ValidateRange] }
+        $enumType = @($originalAttribute)[0].MinRange.GetType()
+        if (-not $enumType.IsEnum) { continue }
+
+        # prefix arguments with [My.Enum.Type]::
+        $enumPrefix = "[$($enumType.FullName)]::"
+        $fixedValidation = $attr.Extent.Text -replace '(\w+)(?=,\s|\)\])', "$enumPrefix`$1"
+
+        if ($PesterPreference.Debug.WriteDebugMessages.Value) {
+            Write-PesterDebugMessage -Scope Mock -Message "Fixed ValidateRange-attribute parameter '$paramName' from '$($attr.Extent.Text)' to '$fixedValidation'"
+        }
+
+        # make sure we modify the correct parameter by modifying the whole thing
+        $orgParameter = $attr.Parent.Extent.Text
+        $fixedParameter = $orgParameter.Replace($attr.Extent.Text, $fixedValidation)
+        $null = $sb.Replace($orgParameter, $fixedParameter)
+    }
+
+    $sb.ToString()
+}
diff --git a/tst/functions/Mock.Tests.ps1 b/tst/functions/Mock.Tests.ps1
@@ -2751,6 +2751,72 @@ Describe 'RemoveParameterValidation' {
     }
 }
 
+Describe 'Mocking command with ValidateRange-attributes' {
+    # https://github.com/pester/Pester/issues/1496
+    # https://github.com/PowerShell/PowerShell/issues/17546
+    # Bug in PowerShell. ProxyCommand-generation breaks ValidateRange-attributes for enum-parameters
+
+    It 'mocked function does not throw when param is <Name>' -TestCases @(
+        @{
+            # min and max are enum-values -> affected by bug, needs Repair-EnumParameters
+            Name      = 'typed using enum min max'
+            Attribute = '[ValidateRange([Microsoft.PowerShell.ExecutionPolicy]::Unrestricted, [Microsoft.PowerShell.ExecutionPolicy]::Undefined)]'
+            Parameter = '[Microsoft.PowerShell.ExecutionPolicy]$TypedBroken'
+        },
+        @{
+            # min and max are enum-values -> affected by bug, needs Repair-EnumParameters
+            Name      = 'untyped using enum min max'
+            Attribute = '[ValidateRange([Microsoft.PowerShell.ExecutionPolicy]::Unrestricted, [Microsoft.PowerShell.ExecutionPolicy]::Undefined)]'
+            Parameter = '$UntypedBroken'
+        },
+        @{
+            # min and max are enum-values -> affected by bug, needs Repair-EnumParameters. make sure regex didn't match partial (Clear)
+            Name      = 'untyped using enum min max with similar valuenames'
+            Attribute = '[ValidateRange([System.ConsoleKey]::Clear, [System.ConsoleKey]::OemClear)]'
+            Parameter = '[Parameter()][System.ConsoleKey]$TypedBrokenWithSimilarAttributeArgNames'
+        },
+        @{
+            # int Min, enum Max -> Both are set as int in command metadata -> unaffected by bug
+            Name      = 'typed using int min enum max'
+            Attribute = '[ValidateRange(0, [Microsoft.PowerShell.ExecutionPolicy]::Undefined)]'
+            Parameter = '[Microsoft.PowerShell.ExecutionPolicy]$Works'
+        },
+        @{
+            # enum Min, int Max -> Both are set as int in command metadata -> unaffected by bug
+            Name      = 'typed using enum min max'
+            Attribute = '[ValidateRange([Microsoft.PowerShell.ExecutionPolicy]::Unrestricted, 0)]'
+            Parameter = '[Microsoft.PowerShell.ExecutionPolicy]$Works2'
+        }
+    ) {
+        Set-Item -Path 'function:Test-EnumValidation' -Value ('param ( {0}{1} )' -f $Attribute, $Parameter)
+
+        Mock -CommandName 'Test-EnumValidation' -MockWith { 'mock' }
+        Test-EnumValidation | Should -Be 'mock'
+    }
+
+    if ($PSVersionTable.PSVersion.Major -ge '7') {
+        # ValidateRangeKind -> unaffected by bug but verify nothing broke
+        It 'mocked function does not throw when param is type using ValidateRangeKind' {
+            $Name = 'typed using RangeKind'
+            $Attribute = '[ValidateRange([System.Management.Automation.ValidateRangeKind]::Positive)]'
+            $Parameter = '[int]$Works2'
+
+            Set-Item -Path 'function:Test-EnumValidation' -Value ('param ( {0}{1} )' -f $Attribute, $Parameter)
+
+            Mock -CommandName 'Test-EnumValidation' -MockWith { 'mock' }
+            Test-EnumValidation | Should -Be 'mock'
+        }
+    }
+
+    # Only built-in cmdlet with affected parameters are Start/Set-BitsTransfer. Only available on Windows
+    if ((Get-Module BitsTransfer -ErrorAction SilentlyContinue)) {
+        It 'mocked cmdlet does not throw' {
+            Mock -CommandName 'Start-BitsTransfer' -MockWith { 'mock' }
+            Start-BitsTransfer -Source "/nonexistingpath" | Should -Be 'mock'
+        }
+    }
+}
+
 Describe "Running Mock with ModuleName in test scope" {
     BeforeAll {
         Get-Module "test" -ErrorAction SilentlyContinue | Remove-Module