Reject whitespace domain filters

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: MariusStorhaug

src/functions/public/Domains/Get-DomeneshopDomain.ps1

@@ -39,6 +39,7 @@ function Get-DomeneshopDomain {
         # A domain-name filter for list requests.
         [Parameter(ParameterSetName = 'List')]
         [ValidateNotNullOrEmpty()]
+        [ValidateScript({ -not [string]::IsNullOrWhiteSpace($_) })]
         [string] $Domain,
 
         # The numeric identifier of a specific domain.

tests/Get-DomeneshopDomain.Tests.ps1

@@ -42,4 +42,10 @@ Describe 'Get-DomeneshopDomain' {
     It 'rejects non-positive domain IDs' {
         { Get-DomeneshopDomain -Context 'demo' -DomainID 0 } | Should -Throw
     }
+
+    It 'rejects whitespace-only domain filters' {
+        { Get-DomeneshopDomain -Context 'demo' -Domain ' ' } | Should -Throw
+
+        Should -Invoke Invoke-DomeneshopApiRequest -Times 0 -Exactly
+    }
 }