Add whitelist to UseSingularNoun rule

Author: Kapil Borle

Rules/UseSingularNouns.cs

@@ -27,6 +27,12 @@ namespace Microsoft.Windows.PowerShell.ScriptAnalyzer.BuiltinRules
     /// </summary>
     [Export(typeof(IScriptRule))]
     public class CmdletSingularNoun : IScriptRule {
+
+        private readonly string[] nounWhiteList =
+        {
+            "Data"
+        };
+
         /// <summary>
         /// Checks that all defined cmdlet use singular noun
         /// </summary>
@@ -57,12 +63,14 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName) {
                     if (!ps.IsSingular(noun) && ps.IsPlural(noun))
                     {
                         IScriptExtent extent = Helper.Instance.GetScriptExtentForFunctionName(funcAst);
-
+                        if (nounWhiteList.Contains(noun, StringComparer.OrdinalIgnoreCase))
+                        {
+                            continue;
+                        }
                         if (null == extent)
                         {
                             extent = funcAst.Extent;
                         }
-
                         yield return new DiagnosticRecord(string.Format(CultureInfo.CurrentCulture, Strings.UseSingularNounsError, funcAst.Name),
                             extent, GetName(), DiagnosticSeverity.Warning, fileName);
                     }

Tests/Rules/UseSingularNounsReservedVerbs.tests.ps1

@@ -24,6 +24,19 @@ Describe "UseSingularNouns" {
 	It "has the correct extent" {
 	   $nounViolations[0].Extent.Text | Should be "Verb-Files"
 	}
+
+    It "excludes items from noun whitelist" {
+        $nounViolationScript = @'
+        Function Add-SomeData 
+        {
+            Write-Output "Adding some data"
+        }
+'@
+        Invoke-ScriptAnalyzer -ScriptDefinition $nounViolationScript `
+            -IncludeRule "PSUseSingularNouns" `
+            -OutVariable violations
+        $violations.Count | Should Be 0
+    }
     }
 
     Context "When there are no violations" {