WIP ReviewUnusedParameter: Search through child scope

Rules/ReviewUnusedParameter.cs

@@ -40,7 +40,7 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
                 IEnumerable<Ast> parameterAsts = scriptBlockAst.FindAll(oneAst => oneAst is ParameterAst, false);
 
                 // list all variables
-                IDictionary<string, int> variableCount = scriptBlockAst.FindAll(oneAst => oneAst is VariableExpressionAst, false)
+                IDictionary<string, int> variableCount = scriptBlockAst.FindAll(oneAst => oneAst is VariableExpressionAst, true)
                     .Select(variableExpressionAst => ((VariableExpressionAst)variableExpressionAst).VariablePath.UserPath)
                     .GroupBy(variableName => variableName, StringComparer.OrdinalIgnoreCase)
                     .ToDictionary(variableName => variableName.Key, variableName => variableName.Count(), StringComparer.OrdinalIgnoreCase);

Tests/Rules/ReviewUnusedParameter.tests.ps1

@@ -23,6 +23,26 @@ Describe "ReviewUnusedParameter" {
             $Violations.Count | Should -Be 1
         }
 
+        It "traverses child scriptblock scope" {
+            $ScriptDefinition = 'param($Param1) { $Param1 }'
+            Invoke-ScriptAnalyzer -ScriptDefinition $ScriptDefinition -IncludeRule $RuleName | Should -BeNullOrEmpty
+        }
+
+        It "traverses child scriptblock scope within simple function" {
+            $ScriptDefinition = 'function foo($Param1) { { $Param1 } }'
+            Invoke-ScriptAnalyzer -ScriptDefinition $ScriptDefinition -IncludeRule $RuleName | Should -BeNullOrEmpty
+        }
+
+        It "traverses child scriptblock scope within a function that uses param" {
+            $ScriptDefinition = 'function foo { param($Param1) { $Param1 } }'
+            Invoke-ScriptAnalyzer -ScriptDefinition $ScriptDefinition -IncludeRule $RuleName | Should -BeNullOrEmpty
+        }
+
+        It "traverse child function within a function" {
+            $ScriptDefinition = 'function foo($Param1) { function bar() { { $Param1 } } }'
+            Invoke-ScriptAnalyzer -ScriptDefinition $ScriptDefinition -IncludeRule $RuleName | Should -BeNullOrEmpty
+        }
+
         It "doesn't traverse scriptblock scope" {
             $ScriptDefinition = '{ param ($Param1) }; { $Param1 }'
             $Violations = Invoke-ScriptAnalyzer -ScriptDefinition $ScriptDefinition -IncludeRule $RuleName