Add -ExcludeDontShow switch to New-MarkdownCommandHelp to suppress [Parameter(DontShow)] parameters

src/Command/NewMarkdownHelpCommand.cs

@@ -132,7 +132,7 @@ protected override void EndProcessing()
                     {
                         CreateModulePage = WithModulePage,
                         DoubleDashList = false,
-                        ExcludeDontShow = false,
+                        ExcludeDontShow = true,
                         FwLink = HelpInfoUri,
                         HelpVersion = HelpVersion.ToString(),
                         Locale = Locale is null ? CultureInfo.CurrentCulture : new CultureInfo(Locale),

src/Transform/TransformBase.cs

@@ -212,6 +212,10 @@ protected IEnumerable<Parameter> GetParameters(CommandInfo cmdletInfo, dynamic?
                 }
 
                 var paramAttribInfo = GetParameterAtributeInfo(parameterMetadata.Value.Attributes);
+                if (Settings.ExcludeDontShow.GetValueOrDefault() && paramAttribInfo.DontShow)
+                {
+                    continue;
+                }
                 string typeName = GetParameterTypeName(parameterMetadata.Value.ParameterType);
 
                 Parameter param = new(parameterMetadata.Value.Name, typeName);
@@ -365,6 +369,11 @@ protected IEnumerable<SyntaxItem> GetSyntaxItem(CommandInfo? cmdletInfo, dynamic
                 // Take the positional parameters first, and order them by position.
                 foreach (CommandParameterInfo paramInfo in parameterSetInfo.Parameters.Where(p => p.Position != int.MinValue).OrderBy(p => p.Position))
                 {
+                    if (Settings.ExcludeDontShow.GetValueOrDefault() && GetParameterAtributeInfo(paramInfo.Attributes).DontShow)
+                    {
+                        continue;
+                    }
+
                     if (IsNotCommonParameter(paramInfo.Name)) {
                         syn.SyntaxParameters.Add(
                             new SyntaxParameter(
@@ -383,6 +392,11 @@ protected IEnumerable<SyntaxItem> GetSyntaxItem(CommandInfo? cmdletInfo, dynamic
                 // now take the named parameters.
                 foreach (CommandParameterInfo paramInfo in parameterSetInfo.Parameters.Where(p => p.Position == int.MinValue))
                 {
+                    if (Settings.ExcludeDontShow.GetValueOrDefault() && GetParameterAtributeInfo(paramInfo.Attributes).DontShow)
+                    {
+                        continue;
+                    }
+
                     if (IsNotCommonParameter(paramInfo.Name)) {
                         var sParm = new SyntaxParameter(
                             paramInfo.Name,

test/Pester/NewMarkdownHelp.Tests.ps1

@@ -657,4 +657,30 @@ Write-Host 'Hello World!'
             $file | Should -FileContentMatch 'Runs the command in a mode that only reports what would happen without performing the actions.'
         }
     }
+
+    Context 'DontShow attribute tests' {
+        BeforeAll {
+            function global:Test-DontShowParameter {
+                [CmdletBinding()]
+                param (
+                    [string] $Public,
+                    [Parameter(DontShow)] [string] $Hidden,
+                    [Parameter(DontShow)] [string] $Break
+                )
+            }
+
+            $file = New-MarkdownCommandHelp -Command (Get-Command 'Test-DontShowParameter') -OutputFolder "$TestDrive/NewMarkDownHelp"
+            $commandHelp = Import-MarkdownCommandHelp $file
+        }
+
+        It 'does not emit hidden parameters in markdown output' {
+            $file | Should -Not -FileContentMatch '### -Hidden'
+            $file | Should -Not -FileContentMatch '### -Break'
+        }
+
+        It 'does not include hidden parameters in the command model' {
+            $commandHelp.Parameters.Name | Should -Be @('Public')
+            $commandHelp.Syntax[0].ToString() | Should -Not -Match 'Hidden|Break'
+        }
+    }
 }