PSReservedParams: Make severity Error instead of Warning (#1989)

Co-authored-by: Christoph Bergmeister <c.bergmeister@gmail.com>

Author: liamjpeters

Rules/AvoidReservedParams.cs

@@ -60,7 +60,7 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName) {
                         if (commonParamNames.Contains(paramName, StringComparer.OrdinalIgnoreCase))
                         {
                             yield return new DiagnosticRecord(string.Format(CultureInfo.CurrentCulture, Strings.ReservedParamsError, funcAst.Name, paramName),
-                                paramAst.Extent, GetName(), DiagnosticSeverity.Warning, fileName);
+                                paramAst.Extent, GetName(), GetDiagnosticSeverity(), fileName);
                         }
                     }
                 }
@@ -107,7 +107,16 @@ public SourceType GetSourceType()
         /// <returns></returns>
         public RuleSeverity GetSeverity()
         {
-            return RuleSeverity.Warning;
+            return RuleSeverity.Error;
+        }
+
+        /// <summary>
+        /// Gets the severity of the returned diagnostic record: error, warning, or information.
+        /// </summary>
+        /// <returns></returns>
+        public DiagnosticSeverity GetDiagnosticSeverity()
+        {
+            return DiagnosticSeverity.Error;
         }
 
         /// <summary>

Tests/Engine/GetScriptAnalyzerRule.tests.ps1

@@ -154,17 +154,17 @@ Describe "Test RuleExtension" {
 Describe "TestSeverity" {
     It "filters rules based on the specified rule severity" {
         $rules = Get-ScriptAnalyzerRule -Severity Error
-        $rules.Count | Should -Be 7
+        $rules.Count | Should -Be 8
     }
 
     It "filters rules based on multiple severity inputs"{
         $rules = Get-ScriptAnalyzerRule -Severity Error,Information
-        $rules.Count | Should -Be 18
+        $rules.Count | Should -Be 19
     }
 
         It "takes lower case inputs" {
         $rules = Get-ScriptAnalyzerRule -Severity error
-        $rules.Count | Should -Be 7
+        $rules.Count | Should -Be 8
     }
 }