Merge pull request #161 from PowerShell/UninitializedVariable

Fix the uninitialized variable throw warning at preference variable

Author: yutingc

Engine/VariableAnalysis.cs

@@ -339,7 +339,8 @@ public bool IsUninitialized(VariableExpressionAst varTarget)
             }
 
             return analysis.DefinedBlock == null
-                && !SpecialVars.InitializedVariables.Contains(analysis.Name, StringComparer.OrdinalIgnoreCase)
+                && !(SpecialVars.InitializedVariables.Contains(analysis.Name, StringComparer.OrdinalIgnoreCase) || 
+                SpecialVars.InitializedVariables.Contains(analysis.RealName, StringComparer.OrdinalIgnoreCase)) 
                 && !IsGlobalOrEnvironment(varTarget);
         }
 

Tests/Rules/AvoidGlobalOrUnitializedVarsNoViolations.ps1

@@ -1,30 +1,41 @@
-function Test {
-    $initialized = "Initialized"
-    $noglobal = "local"
-    $env:ShouldNotRaiseError
-}
-
-$a = 3;
-
-if ($true) {
-    $a = 4;
-    $c = 3;
-} else {
-    $b = 5;
-    $c = 4;
-}
-
-$b = 6;
-$a;
-$b;
-
-stop-process 12,23 -ErrorVariable ev -ErrorAction SilentlyContinue
-if($null -ne $ev)
-{
-    Write-host $ev[0]
-    # no error should be raised here
-    Invoke-Command {$b}
-}
-
-get-process notepad | tee-object -variable proc 
-$proc[0]
+function Test {
+    $initialized = "Initialized"
+    $noglobal = "local"
+    $env:ShouldNotRaiseError
+}
+
+$a = 3;
+
+if ($true) {
+    $a = 4;
+    $c = 3;
+} else {
+    $b = 5;
+    $c = 4;
+}
+
+$b = 6;
+$a;
+$b;
+
+stop-process 12,23 -ErrorVariable ev -ErrorAction SilentlyContinue
+if($null -ne $ev)
+{
+    Write-host $ev[0]
+    # no error should be raised here
+    Invoke-Command {$b}
+}
+
+get-process notepad | tee-object -variable proc 
+$proc[0]
+
+function Test-PreferenceVariable
+{
+
+   if (-not $PSBoundParameters.ContainsKey('Verbose')) {
+       $VerbosePreference = $PSCmdlet.GetVariableValue('VerbosePreference') -as 
+        [System.Management.Automation.ActionPreference]
+        }
+
+        $VerbosePreference
+    }