Add ErrorView to SpecialVars.cs (PowerShell#1865)

* add ErrorView to SpecialVars and create test

* Changed type of ErrorView

Engine/SpecialVars.cs

@@ -91,6 +91,7 @@ static SpecialVars()
         internal const string ConfirmPreference = "ConfirmPreference";
         internal const string ProgressPreference = "ProgressPreference";
         internal const string InformationPreference = "InformationPreference";
+        internal const string ErrorView = "ErrorView";
 
         internal static readonly string[] PreferenceVariables = new string[]
                                                                 {
@@ -101,7 +102,8 @@ static SpecialVars()
                                                                     WarningPreference,
                                                                     ConfirmPreference,
                                                                     ProgressPreference,
-                                                                    InformationPreference
+                                                                    InformationPreference,
+                                                                    ErrorView
                                                                 };
 
         internal static readonly Type[] PreferenceVariableTypes = new Type[]
@@ -114,6 +116,7 @@ static SpecialVars()
                                                                     /* ConfirmPreference */ typeof(ConfirmImpact),
                                                                     /* ProgressPreference */ typeof(Enum),
                                                                     /* InformationPreference */ typeof(ActionPreference),
+                                                                    /* ErrorView */         typeof(Enum), //ErrorView type not available on PS3
                                                                 };
 
         internal enum AutomaticVariable

Tests/Rules/UseDeclaredVarsMoreThanAssignments.tests.ps1

@@ -72,6 +72,11 @@ function MyFunc2() {
     }
 
     Context "When there are no violations" {
+        It "No warning is issued for assignment without use of preference variable ErrorView" {
+            $results = Invoke-ScriptAnalyzer -ScriptDefinition '$ErrorView = NormalView'
+            $results.Count | Should -Be 0
+        }
+
         It "returns no violations" {
             $noViolations.Count | Should -Be 0
         }