AvoidDefaultValueForMandatoryParameter triggers when the field has specification: Mandatory=value and value!=0 (#969)

* AvoidDefaultValueForMandatoryParameter triggers when the field has specification: Mandatory=value and value!=0

* Add tests for AvoidDefaultValueForMandatoryParameter rule.

* Code cleanup for AvoidDefaultValueForMandatoryParameter rule fix.

Author: kalgiz

Rules/AvoidDefaultValueForMandatoryParameter.cs

@@ -51,8 +51,10 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
                                     {
                                         if (String.Equals(namedArgument.ArgumentName, "mandatory", StringComparison.OrdinalIgnoreCase))
                                         {
-                                            // 2 cases: [Parameter(Mandatory)] and [Parameter(Mandatory=$true)]
-                                            if (namedArgument.ExpressionOmitted || (!namedArgument.ExpressionOmitted && String.Equals(namedArgument.Argument.Extent.Text, "$true", StringComparison.OrdinalIgnoreCase)))
+                                            // 3 cases: [Parameter(Mandatory)], [Parameter(Mandatory=$true)] and [Parameter(Mandatory=value)] where value is not equal to 0.
+                                            if (namedArgument.ExpressionOmitted
+                                                || (String.Equals(namedArgument.Argument.Extent.Text, "$true", StringComparison.OrdinalIgnoreCase))
+                                                || (int.TryParse(namedArgument.Argument.Extent.Text, out int mandatoryValue) && mandatoryValue != 0))
                                             {
                                                 mandatory = true;
                                                 break;

Tests/Rules/AvoidDefaultValueForMandatoryParameter.tests.ps1

@@ -13,6 +13,12 @@ Describe "AvoidDefaultValueForMandatoryParameter" {
                 Where-Object { $_.RuleName -eq $ruleName }
             $violations.Count | Should -Be 1
         }
+
+        It "returns violations when the parameter is specified as mandatory=1 and has a default value" {
+            $violations = Invoke-ScriptAnalyzer -ScriptDefinition 'Function foo{ Param([Parameter(Mandatory=1)]$Param1=''defaultValue'') }' |
+                Where-Object { $_.RuleName -eq $ruleName }
+            $violations.Count | Should -Be 1
+        }
     }
 
     Context "When there are no violations" {
@@ -21,5 +27,11 @@ Describe "AvoidDefaultValueForMandatoryParameter" {
                 Where-Object { $_.RuleName -eq $ruleName }
             $violations.Count | Should -Be 0
         }
+
+        It "returns no violations when the parameter is specified as mandatory=0 and has a default value" {
+            $violations = Invoke-ScriptAnalyzer -ScriptDefinition 'Function foo{ Param([Parameter(Mandatory=0)]$Param1=''val1'') }' |
+                Where-Object { $_.RuleName -eq $ruleName }
+            $violations.Count | Should -Be 0
+        }
     }
 }