From 9cac9702598a48666c633344b650066bdfc8a370 Mon Sep 17 00:00:00 2001
From: Hankun Yi <hankyi@microsoft.com>
Date: Thu, 19 Aug 2021 18:40:23 +0800
Subject: [PATCH 1/7] add AvoidMultipleTypesParameter Rule

---
 .../AvoidMultipleTypesParameter.md            | 50 ++++++++++
 RuleDocumentation/README.md                   |  1 +
 Rules/AvoidMultipleTypesParameter.cs          | 98 +++++++++++++++++++
 Rules/Strings.Designer.cs                     | 38 ++++++-
 Rules/Strings.resx                            | 14 ++-
 Tests/Engine/GetScriptAnalyzerRule.tests.ps1  |  2 +-
 Tests/Rules/AvoidMultipleTypesParameter.ps1   |  7 ++
 .../AvoidMultipleTypesParameter.tests.ps1     | 25 +++++
 ...voidMultipleTypesParameterNoViolations.ps1 |  3 +
 9 files changed, 235 insertions(+), 3 deletions(-)
 create mode 100644 RuleDocumentation/AvoidMultipleTypesParameter.md
 create mode 100644 Rules/AvoidMultipleTypesParameter.cs
 create mode 100644 Tests/Rules/AvoidMultipleTypesParameter.ps1
 create mode 100644 Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
 create mode 100644 Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1

diff --git a/RuleDocumentation/AvoidMultipleTypesParameter.md b/RuleDocumentation/AvoidMultipleTypesParameter.md
new file mode 100644
index 000000000..4879a7ff3
--- /dev/null
+++ b/RuleDocumentation/AvoidMultipleTypesParameter.md
@@ -0,0 +1,50 @@
+# AvoidMultipleTypesParameter
+
+**Severity Level: Warning**
+
+## Description
+
+Parameter should not have more than one type specifier.
+
+## How
+
+Make each parameter has only 1 type spcifier.
+
+## Example
+
+### Wrong
+
+``` PowerShell
+function Test-Script
+{
+    [CmdletBinding()]
+    Param
+    (
+        [String]
+        $Param1,
+
+        [switch]
+        [boolean]
+        $Switch=$True
+    )
+    ...
+}
+```
+
+### Correct
+
+``` PowerShell
+function Test-Script
+{
+    [CmdletBinding()]
+    Param
+    (
+        [String]
+        $Param1,
+
+        [switch]
+        $Switch=$False
+    )
+    ...
+}
+```
diff --git a/RuleDocumentation/README.md b/RuleDocumentation/README.md
index 551ad55f5..db4671f4e 100644
--- a/RuleDocumentation/README.md
+++ b/RuleDocumentation/README.md
@@ -13,6 +13,7 @@
 |[AvoidGlobalVars](./AvoidGlobalVars.md) | Warning | |
 |[AvoidInvokingEmptyMembers](./AvoidInvokingEmptyMembers.md) | Warning | |
 |[AvoidLongLines](./AvoidLongLines.md) | Warning | |
+|[AvoidMultipleTypesParameter](./AvoidMultipleTypesParameter.md) | Warning | |
 |[AvoidOverwritingBuiltInCmdlets](./AvoidOverwritingBuiltInCmdlets.md) | Warning | |
 |[AvoidNullOrEmptyHelpMessageAttribute](./AvoidNullOrEmptyHelpMessageAttribute.md) | Warning | |
 |[AvoidShouldContinueWithoutForce](./AvoidShouldContinueWithoutForce.md) | Warning | |
diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypesParameter.cs
new file mode 100644
index 000000000..766436f78
--- /dev/null
+++ b/Rules/AvoidMultipleTypesParameter.cs
@@ -0,0 +1,98 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Management.Automation.Language;
+using Microsoft.Windows.PowerShell.ScriptAnalyzer.Generic;
+#if !CORECLR
+using System.ComponentModel.Composition;
+#endif
+using System.Globalization;
+
+namespace Microsoft.Windows.PowerShell.ScriptAnalyzer.BuiltinRules
+{
+    /// <summary>
+    /// AvoidMultipleTypesParameter: Check that parameter does not be assigned to multiple types.
+    /// </summary>
+#if !CORECLR
+    [Export(typeof(IScriptRule))]
+#endif
+    public sealed class AvoidMultipleTypesParameter : IScriptRule
+    {
+        /// <summary>
+        /// AvoidMultipleTypesParameter: Check that parameter does not be assigned to multiple types.
+        /// </summary>
+        public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
+        {
+            if (ast == null) throw new ArgumentNullException(Strings.NullAstErrorMessage);
+
+            // Finds all ParamAsts.
+            IEnumerable<Ast> paramAsts = ast.FindAll(testAst => testAst is ParameterAst, true);
+
+            // Iterates all ParamAsts and check the number of its types.
+            foreach (ParameterAst paramAst in paramAsts)
+            {
+                if (paramAst.Attributes.Where(typeAst => typeAst is TypeConstraintAst).Count() > 1)
+                {
+                    yield return new DiagnosticRecord(
+                        String.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterError, paramAst.Name),
+                        paramAst.Name.Extent, GetName(), DiagnosticSeverity.Warning, fileName);
+                }
+            }
+        }
+    
+        /// <summary>
+        /// GetName: Retrieves the name of this rule.
+        /// </summary>
+        /// <returns>The name of this rule</returns>
+        public string GetName()
+        {
+            return string.Format(CultureInfo.CurrentCulture, Strings.NameSpaceFormat, GetSourceName(), Strings.AvoidMultipleTypesParameterName);
+        }
+
+        /// <summary>
+        /// GetCommonName: Retrieves the common name of this rule.
+        /// </summary>
+        /// <returns>The common name of this rule</returns>
+        public string GetCommonName()
+        {
+            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterCommonName);
+        }
+
+        /// <summary>
+        /// GetDescription: Retrieves the description of this rule.
+        /// </summary>
+        /// <returns>The description of this rule</returns>
+        public string GetDescription()
+        {
+            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterDescription);
+        }
+
+        /// <summary>
+        /// GetSourceType: Retrieves the type of the rule, Builtin, Managed or Module.
+        /// </summary>
+        public SourceType GetSourceType()
+        {
+            return SourceType.Builtin;
+        }
+
+        /// <summary>
+        /// GetSeverity: Retrieves the severity of the rule: error, warning or information.
+        /// </summary>
+        /// <returns></returns>
+        public RuleSeverity GetSeverity()
+        {
+            return RuleSeverity.Warning;
+        }
+
+        /// <summary>
+        /// GetSourceName: Retrieves the name of the module/assembly the rule is from.
+        /// </summary>
+        public string GetSourceName()
+        {
+            return string.Format(CultureInfo.CurrentCulture, Strings.SourceName);
+        }
+    }
+}
\ No newline at end of file
diff --git a/Rules/Strings.Designer.cs b/Rules/Strings.Designer.cs
index 70cda2d94..bd212211b 100644
--- a/Rules/Strings.Designer.cs
+++ b/Rules/Strings.Designer.cs
@@ -465,6 +465,42 @@ internal static string AvoidLongLinesName {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Avoid Multiple Types Parameter.
+        /// </summary>
+        internal static string AvoidMultipleTypesParameterCommonName {
+            get {
+                return ResourceManager.GetString("AvoidMultipleTypesParameterCommonName", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Prameter should not have more than one type specifier..
+        /// </summary>
+        internal static string AvoidMultipleTypesParameterDescription {
+            get {
+                return ResourceManager.GetString("AvoidMultipleTypesParameterDescription", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Parameter &apos;{0}&apos; has more than one type specifier..
+        /// </summary>
+        internal static string AvoidMultipleTypesParameterError {
+            get {
+                return ResourceManager.GetString("AvoidMultipleTypesParameterError", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to AvoidMultipleTypesParameter.
+        /// </summary>
+        internal static string AvoidMultipleTypesParameterName {
+            get {
+                return ResourceManager.GetString("AvoidMultipleTypesParameterName", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Avoid using null or empty HelpMessage parameter attribute..
         /// </summary>
@@ -1285,7 +1321,7 @@ internal static string DscTestsPresentNoTestsError {
         }
         
         /// <summary>
-        ///   Looks up a localized string similar to When using a process block, only a begin or end block is allowed inside the function but no code..
+        ///   Looks up a localized string similar to When using an explicit process block, no preceding code is allowed, only begin, end and dynamicparams blocks..
         /// </summary>
         internal static string InvalidSyntaxAroundProcessBlockError {
             get {
diff --git a/Rules/Strings.resx b/Rules/Strings.resx
index 120ead158..6ca4d84aa 100644
--- a/Rules/Strings.resx
+++ b/Rules/Strings.resx
@@ -1152,4 +1152,16 @@
   <data name="InvalidSyntaxAroundProcessBlockError" xml:space="preserve">
     <value>When using an explicit process block, no preceding code is allowed, only begin, end and dynamicparams blocks.</value>
   </data>
-</root>
+  <data name="AvoidMultipleTypesParameterCommonName" xml:space="preserve">
+    <value>Avoid Multiple Types Parameter</value>
+  </data>
+  <data name="AvoidMultipleTypesParameterDescription" xml:space="preserve">
+    <value>Prameter should not have more than one type specifier.</value>
+  </data>
+  <data name="AvoidMultipleTypesParameterError" xml:space="preserve">
+    <value>Parameter '{0}' has more than one type specifier.</value>
+  </data>
+  <data name="AvoidMultipleTypesParameterName" xml:space="preserve">
+    <value>AvoidMultipleTypesParameter</value>
+  </data>
+</root>
\ No newline at end of file
diff --git a/Tests/Engine/GetScriptAnalyzerRule.tests.ps1 b/Tests/Engine/GetScriptAnalyzerRule.tests.ps1
index e5e2159bd..50a6f0077 100644
--- a/Tests/Engine/GetScriptAnalyzerRule.tests.ps1
+++ b/Tests/Engine/GetScriptAnalyzerRule.tests.ps1
@@ -63,7 +63,7 @@ Describe "Test Name parameters" {
 
         It "get Rules with no parameters supplied" {
             $defaultRules = Get-ScriptAnalyzerRule
-            $expectedNumRules = 65
+            $expectedNumRules = 66
             if ($PSVersionTable.PSVersion.Major -le 4)
             {
                 # for PSv3 PSAvoidGlobalAliases is not shipped because
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.ps1
new file mode 100644
index 000000000..082f911c5
--- /dev/null
+++ b/Tests/Rules/AvoidMultipleTypesParameter.ps1
@@ -0,0 +1,7 @@
+# Double typing is not allowed
+function F10 ([int] [switch] $s1, [int] $p1){}
+
+# Double typing is not allowed even for switch and boolean, because:
+# switch maps to System.Management.Automation.SwitchParameter
+# boolean maps to System.Boolean
+function F11 ([switch][boolean] $s1, [int] $p1){}
\ No newline at end of file
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
new file mode 100644
index 000000000..fc7a3c85b
--- /dev/null
+++ b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
@@ -0,0 +1,25 @@
+BeforeAll {
+    $violationMessage = 'Parameter ''\$s1'' has more than one type specifier.'
+    $violationName = "PSAvoidMultipleTypesParameter"
+    $violations = Invoke-ScriptAnalyzer $PSScriptRoot\AvoidMultipleTypesParameter.ps1 | Where-Object {$_.RuleName -eq $violationName}
+    $noViolations = Invoke-ScriptAnalyzer $PSScriptRoot\AvoidMultipleTypesParameterNoViolations.ps1 | Where-Object {$_.RuleName -eq $violationName}
+}
+
+Describe "AvoidMultipleTypesParameter" {
+    Context "When there are violations" {
+        It "has two AvoidMultipleTypesParameter violations" {
+            $violations.Count | Should -Be 2
+        }
+
+        It "has the correct description message" {
+            $violations[0].Message | Should -Match $violationMessage
+            $violations[1].Message | Should -Match $violationMessage
+        }
+    }
+
+    Context "When there are no violations" {
+        It "returns no violations" {
+            $noViolations.Count | Should -Be 0
+        }
+    }
+}
\ No newline at end of file
diff --git a/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1 b/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1
new file mode 100644
index 000000000..79636e48a
--- /dev/null
+++ b/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1
@@ -0,0 +1,3 @@
+function F10 ([int] $s1, [int] $p1){}
+
+function F11 ([switch] $s1, [int] $p1){}
\ No newline at end of file

From 6f3e303cb1a04699666c0c141723847c33d7e80c Mon Sep 17 00:00:00 2001
From: hankyi95 <89194767+hankyi95@users.noreply.github.com>
Date: Fri, 20 Aug 2021 16:48:08 +0800
Subject: [PATCH 2/7] resolve some comments

---
 Rules/AvoidMultipleTypesParameter.cs          |  2 +-
 Rules/Strings.resx                            |  2 +-
 Tests/Rules/AvoidMultipleTypesParameter.ps1   |  7 ----
 .../AvoidMultipleTypesParameter.tests.ps1     | 36 ++++++++++++++-----
 ...voidMultipleTypesParameterNoViolations.ps1 |  3 --
 5 files changed, 30 insertions(+), 20 deletions(-)
 delete mode 100644 Tests/Rules/AvoidMultipleTypesParameter.ps1
 delete mode 100644 Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1

diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypesParameter.cs
index 766436f78..4f0db6236 100644
--- a/Rules/AvoidMultipleTypesParameter.cs
+++ b/Rules/AvoidMultipleTypesParameter.cs
@@ -95,4 +95,4 @@ public string GetSourceName()
             return string.Format(CultureInfo.CurrentCulture, Strings.SourceName);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Rules/Strings.resx b/Rules/Strings.resx
index 6ca4d84aa..73167ad48 100644
--- a/Rules/Strings.resx
+++ b/Rules/Strings.resx
@@ -1164,4 +1164,4 @@
   <data name="AvoidMultipleTypesParameterName" xml:space="preserve">
     <value>AvoidMultipleTypesParameter</value>
   </data>
-</root>
\ No newline at end of file
+</root>
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.ps1
deleted file mode 100644
index 082f911c5..000000000
--- a/Tests/Rules/AvoidMultipleTypesParameter.ps1
+++ /dev/null
@@ -1,7 +0,0 @@
-# Double typing is not allowed
-function F10 ([int] [switch] $s1, [int] $p1){}
-
-# Double typing is not allowed even for switch and boolean, because:
-# switch maps to System.Management.Automation.SwitchParameter
-# boolean maps to System.Boolean
-function F11 ([switch][boolean] $s1, [int] $p1){}
\ No newline at end of file
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
index fc7a3c85b..4a90d1084 100644
--- a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
+++ b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
@@ -1,12 +1,24 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
+
 BeforeAll {
-    $violationMessage = 'Parameter ''\$s1'' has more than one type specifier.'
-    $violationName = "PSAvoidMultipleTypesParameter"
-    $violations = Invoke-ScriptAnalyzer $PSScriptRoot\AvoidMultipleTypesParameter.ps1 | Where-Object {$_.RuleName -eq $violationName}
-    $noViolations = Invoke-ScriptAnalyzer $PSScriptRoot\AvoidMultipleTypesParameterNoViolations.ps1 | Where-Object {$_.RuleName -eq $violationName}
+    $ruleName = "PSAvoidMultipleTypesParameter"
+
+    $settings = @{
+        IncludeRules = @($ruleName)
+    }
 }
 
-Describe "AvoidMultipleTypesParameter" {
-    Context "When there are violations" {
+Describe 'AvoidMultipleTypesParameter' {
+    Context 'When there are violations' {
+        BeforeAll {
+            $scriptDefinition = @'
+function F10 ([int][switch] $s1, [int] $p1){}
+function F11 ([switch][boolean] $s1, [int] $p1){}
+'@
+            $violations = Invoke-ScriptAnalyzer -ScriptDefinition $scriptDefinition -Settings $settings
+            $violationMessage = 'Parameter ''\$s1'' has more than one type specifier.'
+        }
         It "has two AvoidMultipleTypesParameter violations" {
             $violations.Count | Should -Be 2
         }
@@ -18,8 +30,16 @@ Describe "AvoidMultipleTypesParameter" {
     }
 
     Context "When there are no violations" {
+        BeforeAll {
+            $scriptDefinition = @'
+function F10 ([switch] $s1, [int] $p1){}
+function F11 ([boolean] $s1, [int] $p1){}
+'@
+            $violations = Invoke-ScriptAnalyzer -ScriptDefinition $scriptDefinition -Settings $settings
+        }
+
         It "returns no violations" {
-            $noViolations.Count | Should -Be 0
+            $violations.Count | Should -Be 0
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1 b/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1
deleted file mode 100644
index 79636e48a..000000000
--- a/Tests/Rules/AvoidMultipleTypesParameterNoViolations.ps1
+++ /dev/null
@@ -1,3 +0,0 @@
-function F10 ([int] $s1, [int] $p1){}
-
-function F11 ([switch] $s1, [int] $p1){}
\ No newline at end of file

From 5498863b31c4c587f36520a9e350d6761580a4b3 Mon Sep 17 00:00:00 2001
From: hankyi95 <89194767+hankyi95@users.noreply.github.com>
Date: Mon, 23 Aug 2021 10:25:20 +0800
Subject: [PATCH 3/7] Update Rules/AvoidMultipleTypesParameter.cs

Co-authored-by: Robert Holt <rjmholt@gmail.com>
---
 Rules/AvoidMultipleTypesParameter.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypesParameter.cs
index 4f0db6236..4954850d7 100644
--- a/Rules/AvoidMultipleTypesParameter.cs
+++ b/Rules/AvoidMultipleTypesParameter.cs
@@ -29,7 +29,7 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
             if (ast == null) throw new ArgumentNullException(Strings.NullAstErrorMessage);
 
             // Finds all ParamAsts.
-            IEnumerable<Ast> paramAsts = ast.FindAll(testAst => testAst is ParameterAst, true);
+            IEnumerable<Ast> paramAsts = ast.FindAll(testAst => testAst is ParameterAst, searchNestedScriptBlocks: true);
 
             // Iterates all ParamAsts and check the number of its types.
             foreach (ParameterAst paramAst in paramAsts)

From 00b03cc4da3b430e1dfa3441e27b260b6e2318bc Mon Sep 17 00:00:00 2001
From: hankyi95 <89194767+hankyi95@users.noreply.github.com>
Date: Wed, 25 Aug 2021 15:56:34 +0800
Subject: [PATCH 4/7] add more test case

---
 .../AvoidMultipleTypesParameter.md            |  8 +-
 Rules/AvoidMultipleTypesParameter.cs          | 10 ++-
 Rules/Strings.resx                            |  2 +-
 .../AvoidMultipleTypesParameter.tests.ps1     | 75 ++++++++++++-------
 4 files changed, 63 insertions(+), 32 deletions(-)

diff --git a/RuleDocumentation/AvoidMultipleTypesParameter.md b/RuleDocumentation/AvoidMultipleTypesParameter.md
index 4879a7ff3..0cdc85802 100644
--- a/RuleDocumentation/AvoidMultipleTypesParameter.md
+++ b/RuleDocumentation/AvoidMultipleTypesParameter.md
@@ -4,11 +4,11 @@
 
 ## Description
 
-Parameter should not have more than one type specifier.
+Parameters should not have more than one type specifier. Multiple type specifiers on parameters will cause a runtime error.
 
 ## How
 
-Make each parameter has only 1 type spcifier.
+Ensure each parameter has only 1 type spcifier.
 
 ## Example
 
@@ -25,7 +25,7 @@ function Test-Script
 
         [switch]
         [boolean]
-        $Switch=$True
+        $Switch
     )
     ...
 }
@@ -43,7 +43,7 @@ function Test-Script
         $Param1,
 
         [switch]
-        $Switch=$False
+        $Switch
     )
     ...
 }
diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypesParameter.cs
index 4f0db6236..e5a720554 100644
--- a/Rules/AvoidMultipleTypesParameter.cs
+++ b/Rules/AvoidMultipleTypesParameter.cs
@@ -26,7 +26,10 @@ public sealed class AvoidMultipleTypesParameter : IScriptRule
         /// </summary>
         public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
         {
-            if (ast == null) throw new ArgumentNullException(Strings.NullAstErrorMessage);
+            if (ast == null) 
+            {
+                throw new ArgumentNullException(Strings.NullAstErrorMessage);
+            }
 
             // Finds all ParamAsts.
             IEnumerable<Ast> paramAsts = ast.FindAll(testAst => testAst is ParameterAst, true);
@@ -38,7 +41,10 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
                 {
                     yield return new DiagnosticRecord(
                         String.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterError, paramAst.Name),
-                        paramAst.Name.Extent, GetName(), DiagnosticSeverity.Warning, fileName);
+                        paramAst.Name.Extent,
+                        GetName(), 
+                        DiagnosticSeverity.Warning, 
+                        fileName);
                 }
             }
         }
diff --git a/Rules/Strings.resx b/Rules/Strings.resx
index 73167ad48..5cb403af1 100644
--- a/Rules/Strings.resx
+++ b/Rules/Strings.resx
@@ -1153,7 +1153,7 @@
     <value>When using an explicit process block, no preceding code is allowed, only begin, end and dynamicparams blocks.</value>
   </data>
   <data name="AvoidMultipleTypesParameterCommonName" xml:space="preserve">
-    <value>Avoid Multiple Types Parameter</value>
+    <value>Avoid multiple type specifiers on parameters</value>
   </data>
   <data name="AvoidMultipleTypesParameterDescription" xml:space="preserve">
     <value>Prameter should not have more than one type specifier.</value>
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
index 4a90d1084..f0409145d 100644
--- a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
+++ b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
@@ -10,36 +10,61 @@ BeforeAll {
 }
 
 Describe 'AvoidMultipleTypesParameter' {
-    Context 'When there are violations' {
-        BeforeAll {
-            $scriptDefinition = @'
-function F10 ([int][switch] $s1, [int] $p1){}
-function F11 ([switch][boolean] $s1, [int] $p1){}
+    it 'Should find 3 violations for paramters have more than one type spceifiers' {
+        $def = @'
+function F1 ($s1, $p1){}
+function F2 ([int] $s2, [int] $p2){}
+function F3 ([int][switch] $s3, [int] $p3){}
+function F4 ([int][ref] $s4, [int] $p4){}
+function F5 ([int][switch][boolean] $s5, [int] $p5){}
 '@
-            $violations = Invoke-ScriptAnalyzer -ScriptDefinition $scriptDefinition -Settings $settings
-            $violationMessage = 'Parameter ''\$s1'' has more than one type specifier.'
-        }
-        It "has two AvoidMultipleTypesParameter violations" {
-            $violations.Count | Should -Be 2
-        }
+        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations.Count | Should -Be 3
+    }
 
-        It "has the correct description message" {
-            $violations[0].Message | Should -Match $violationMessage
-            $violations[1].Message | Should -Match $violationMessage
-        }
+    it 'Should get the correct extent of the violation ' {
+        $def = @'
+function F1 ($s1, $p1){}
+function F2 ([int] $s2, [int] $p2){}
+function F3 ([int][switch] $s3, [int] $p3){}
+function F4 ([int][ref] $s4, [int] $p4){}
+function F5 ([int][switch][boolean] $s5, [int] $p5){}
+'@
+        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations[0].Extent.StartLineNumber | Should -Be 3
+        $violations[0].Extent.EndLineNumber | Should -Be 3
+        $violations[1].Extent.StartLineNumber | Should -Be 4
+        $violations[1].Extent.EndLineNumber | Should -Be 4
+        $violations[2].Extent.StartLineNumber | Should -Be 5
+        $violations[2].Extent.EndLineNumber | Should -Be 5
     }
 
-    Context "When there are no violations" {
-        BeforeAll {
-            $scriptDefinition = @'
-function F10 ([switch] $s1, [int] $p1){}
-function F11 ([boolean] $s1, [int] $p1){}
+    it 'Should get the correct error messaage of the violation ' {
+        $def = @'
+function F1 ($s1, $p1){}
+function F2 ([int] $s2, [int] $p2){}
+function F3 ([int][switch] $s3, [int] $p3){}
+function F4 ([int][ref] $s4, [int] $p4){}
+function F5 ([int][switch][boolean] $s5, [int] $p5){}
 '@
-            $violations = Invoke-ScriptAnalyzer -ScriptDefinition $scriptDefinition -Settings $settings
-        }
+        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations[0].Message | Should -Match 'Parameter ''\$s3'' has more than one type specifier.'
+        $violations[1].Message | Should -Match 'Parameter ''\$s4'' has more than one type specifier.'
+        $violations[2].Message | Should -Match 'Parameter ''\$s5'' has more than one type specifier.'
+    }
 
-        It "returns no violations" {
-            $violations.Count | Should -Be 0
-        }
+    it 'Should not have violations for paramters have one or less type spceifier' {
+        $def = @'
+function F1 ($s1, $p1){}
+function F2 ([int] $s2, [int] $p2){}
+function F3 ([ValidateSet()][int] $s3, [int] $p3){}
+function F4 ([Parameter(Mandatory=$true)][ValidateSet()][int] $s4, [int] $p4){}
+'@
+        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
+        $violations.Count | Should -Be 0
     }
 }

From 2c5c3e8fa61a17c6fd0d61924bbfa8f06472d5fb Mon Sep 17 00:00:00 2001
From: hankyi95 <89194767+hankyi95@users.noreply.github.com>
Date: Thu, 26 Aug 2021 14:37:49 +0800
Subject: [PATCH 5/7] refactor test case

---
 Rules/AvoidMultipleTypesParameter.cs          |  2 +-
 .../AvoidMultipleTypesParameter.tests.ps1     | 78 ++++++-------------
 2 files changed, 26 insertions(+), 54 deletions(-)

diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypesParameter.cs
index 91a5b3a79..64f536635 100644
--- a/Rules/AvoidMultipleTypesParameter.cs
+++ b/Rules/AvoidMultipleTypesParameter.cs
@@ -26,7 +26,7 @@ public sealed class AvoidMultipleTypesParameter : IScriptRule
         /// </summary>
         public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
         {
-            if (ast == null) 
+            if (ast is null) 
             {
                 throw new ArgumentNullException(Strings.NullAstErrorMessage);
             }
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1 b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
index f0409145d..fd3016fb4 100644
--- a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
+++ b/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
@@ -10,61 +10,33 @@ BeforeAll {
 }
 
 Describe 'AvoidMultipleTypesParameter' {
-    it 'Should find 3 violations for paramters have more than one type spceifiers' {
-        $def = @'
-function F1 ($s1, $p1){}
-function F2 ([int] $s2, [int] $p2){}
-function F3 ([int][switch] $s3, [int] $p3){}
-function F4 ([int][ref] $s4, [int] $p4){}
-function F5 ([int][switch][boolean] $s5, [int] $p5){}
-'@
-        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations.Count | Should -Be 3
-    }
+    It 'Correctly diagnoses and corrects <Script>' -TestCases @(
+        @{ Script = 'function F1 ($s1, $p1){}' }
+        @{ Script = 'function F2 ([int] $s2, [int] $p2){}' }
+        @{ Script = 'function F3 ([int][switch] $s3, [int] $p3){}';Extent = @{ StartCol = 28; EndCol = 31 }; Message = 'Parameter ''$s3'' has more than one type specifier.' }
+        @{ Script = 'function F4 ([int][ref] $s4, [int] $p4){}';Extent = @{ StartCol = 25; EndCol = 28 }; Message = 'Parameter ''$s4'' has more than one type specifier.' }
+        @{ Script = 'function F5 ([int][switch][boolean] $s5, [int] $p5){}';Extent = @{ StartCol = 37; EndCol = 40 }; Message = 'Parameter ''$s5'' has more than one type specifier.' }
+        @{ Script = 'function F6 ([ValidateSet()][int] $s6, [int] $p6){}' }
+        @{ Script = 'function F7 ([Parameter(Mandatory=$true)][ValidateSet()][int] $s7, [int] $p7){}' }
+    ) {
+        param([string]$Script, $Extent, $Message)
 
-    it 'Should get the correct extent of the violation ' {
-        $def = @'
-function F1 ($s1, $p1){}
-function F2 ([int] $s2, [int] $p2){}
-function F3 ([int][switch] $s3, [int] $p3){}
-function F4 ([int][ref] $s4, [int] $p4){}
-function F5 ([int][switch][boolean] $s5, [int] $p5){}
-'@
-        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations[0].Extent.StartLineNumber | Should -Be 3
-        $violations[0].Extent.EndLineNumber | Should -Be 3
-        $violations[1].Extent.StartLineNumber | Should -Be 4
-        $violations[1].Extent.EndLineNumber | Should -Be 4
-        $violations[2].Extent.StartLineNumber | Should -Be 5
-        $violations[2].Extent.EndLineNumber | Should -Be 5
-    }
+        $diagnostics = Invoke-ScriptAnalyzer -ScriptDefinition $Script
 
-    it 'Should get the correct error messaage of the violation ' {
-        $def = @'
-function F1 ($s1, $p1){}
-function F2 ([int] $s2, [int] $p2){}
-function F3 ([int][switch] $s3, [int] $p3){}
-function F4 ([int][ref] $s4, [int] $p4){}
-function F5 ([int][switch][boolean] $s5, [int] $p5){}
-'@
-        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations[0].Message | Should -Match 'Parameter ''\$s3'' has more than one type specifier.'
-        $violations[1].Message | Should -Match 'Parameter ''\$s4'' has more than one type specifier.'
-        $violations[2].Message | Should -Match 'Parameter ''\$s5'' has more than one type specifier.'
-    }
+        if (-not $Extent)
+        {
+            $diagnostics | Should -BeNullOrEmpty
+            return
+        }
+
+        $expectedStartLine = if ($Extent.StartLine) { $Extent.StartLine } else { 1 }
+        $expectedEndLine = if ($Extent.EndLine) { $Extent.EndLine } else { 1 }
+
+        $diagnostics.Extent.StartLineNumber | Should -BeExactly $expectedStartLine
+        $diagnostics.Extent.EndLineNumber | Should -BeExactly $expectedEndLine
+        $diagnostics.Extent.StartColumnNumber | Should -BeExactly $Extent.StartCol
+        $diagnostics.Extent.EndColumnNumber | Should -BeExactly $Extent.EndCol
 
-    it 'Should not have violations for paramters have one or less type spceifier' {
-        $def = @'
-function F1 ($s1, $p1){}
-function F2 ([int] $s2, [int] $p2){}
-function F3 ([ValidateSet()][int] $s3, [int] $p3){}
-function F4 ([Parameter(Mandatory=$true)][ValidateSet()][int] $s4, [int] $p4){}
-'@
-        Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations = Invoke-ScriptAnalyzer -ScriptDefinition $def -Settings $settings
-        $violations.Count | Should -Be 0
+        $diagnostics.Message | Should -BeExactly $Message
     }
 }

From 28caac803d2546e74a3de905d53ced7be8185d35 Mon Sep 17 00:00:00 2001
From: Robert Holt <rjmholt@gmail.com>
Date: Thu, 26 Aug 2021 10:28:44 -0700
Subject: [PATCH 6/7] Apply suggestions from code review

---
 RuleDocumentation/AvoidMultipleTypesParameter.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/RuleDocumentation/AvoidMultipleTypesParameter.md b/RuleDocumentation/AvoidMultipleTypesParameter.md
index 0cdc85802..0d5bb5e41 100644
--- a/RuleDocumentation/AvoidMultipleTypesParameter.md
+++ b/RuleDocumentation/AvoidMultipleTypesParameter.md
@@ -8,7 +8,7 @@ Parameters should not have more than one type specifier. Multiple type specifier
 
 ## How
 
-Ensure each parameter has only 1 type spcifier.
+Ensure each parameter has only 1 type specifier.
 
 ## Example
 
@@ -24,7 +24,7 @@ function Test-Script
         $Param1,
 
         [switch]
-        [boolean]
+        [bool]
         $Switch
     )
     ...

From 9f8aa7eec0554990c5f9a26c0581c91be16bb43d Mon Sep 17 00:00:00 2001
From: hankyi95 <89194767+hankyi95@users.noreply.github.com>
Date: Fri, 27 Aug 2021 14:12:39 +0800
Subject: [PATCH 7/7] change rule name to AvoidMultipleTypeAttributes

---
 ...eter.md => AvoidMultipleTypeAttributes.md} |  2 +-
 RuleDocumentation/README.md                   |  2 +-
 ...eter.cs => AvoidMultipleTypeAttributes.cs} | 14 ++++++-------
 Rules/Strings.Designer.cs                     | 20 +++++++++----------
 Rules/Strings.resx                            | 10 +++++-----
 ... => AvoidMultipleTypeAttributes.tests.ps1} |  4 ++--
 6 files changed, 26 insertions(+), 26 deletions(-)
 rename RuleDocumentation/{AvoidMultipleTypesParameter.md => AvoidMultipleTypeAttributes.md} (95%)
 rename Rules/{AvoidMultipleTypesParameter.cs => AvoidMultipleTypeAttributes.cs} (90%)
 rename Tests/Rules/{AvoidMultipleTypesParameter.tests.ps1 => AvoidMultipleTypeAttributes.tests.ps1} (95%)

diff --git a/RuleDocumentation/AvoidMultipleTypesParameter.md b/RuleDocumentation/AvoidMultipleTypeAttributes.md
similarity index 95%
rename from RuleDocumentation/AvoidMultipleTypesParameter.md
rename to RuleDocumentation/AvoidMultipleTypeAttributes.md
index 0cdc85802..88a4dd2ed 100644
--- a/RuleDocumentation/AvoidMultipleTypesParameter.md
+++ b/RuleDocumentation/AvoidMultipleTypeAttributes.md
@@ -1,4 +1,4 @@
-# AvoidMultipleTypesParameter
+# AvoidMultipleTypeAttributes
 
 **Severity Level: Warning**
 
diff --git a/RuleDocumentation/README.md b/RuleDocumentation/README.md
index db4671f4e..25338085a 100644
--- a/RuleDocumentation/README.md
+++ b/RuleDocumentation/README.md
@@ -13,7 +13,7 @@
 |[AvoidGlobalVars](./AvoidGlobalVars.md) | Warning | |
 |[AvoidInvokingEmptyMembers](./AvoidInvokingEmptyMembers.md) | Warning | |
 |[AvoidLongLines](./AvoidLongLines.md) | Warning | |
-|[AvoidMultipleTypesParameter](./AvoidMultipleTypesParameter.md) | Warning | |
+|[AvoidMultipleTypeAttributes](./AvoidMultipleTypeAttributes.md) | Warning | |
 |[AvoidOverwritingBuiltInCmdlets](./AvoidOverwritingBuiltInCmdlets.md) | Warning | |
 |[AvoidNullOrEmptyHelpMessageAttribute](./AvoidNullOrEmptyHelpMessageAttribute.md) | Warning | |
 |[AvoidShouldContinueWithoutForce](./AvoidShouldContinueWithoutForce.md) | Warning | |
diff --git a/Rules/AvoidMultipleTypesParameter.cs b/Rules/AvoidMultipleTypeAttributes.cs
similarity index 90%
rename from Rules/AvoidMultipleTypesParameter.cs
rename to Rules/AvoidMultipleTypeAttributes.cs
index 64f536635..77f63de21 100644
--- a/Rules/AvoidMultipleTypesParameter.cs
+++ b/Rules/AvoidMultipleTypeAttributes.cs
@@ -14,15 +14,15 @@
 namespace Microsoft.Windows.PowerShell.ScriptAnalyzer.BuiltinRules
 {
     /// <summary>
-    /// AvoidMultipleTypesParameter: Check that parameter does not be assigned to multiple types.
+    /// AvoidMultipleTypeAttributes: Check that parameter does not be assigned to multiple types.
     /// </summary>
 #if !CORECLR
     [Export(typeof(IScriptRule))]
 #endif
-    public sealed class AvoidMultipleTypesParameter : IScriptRule
+    public sealed class AvoidMultipleTypeAttributes : IScriptRule
     {
         /// <summary>
-        /// AvoidMultipleTypesParameter: Check that parameter does not be assigned to multiple types.
+        /// AvoidMultipleTypeAttributes: Check that parameter does not be assigned to multiple types.
         /// </summary>
         public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
         {
@@ -40,7 +40,7 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
                 if (paramAst.Attributes.Where(typeAst => typeAst is TypeConstraintAst).Count() > 1)
                 {
                     yield return new DiagnosticRecord(
-                        String.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterError, paramAst.Name),
+                        String.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypeAttributesError, paramAst.Name),
                         paramAst.Name.Extent,
                         GetName(), 
                         DiagnosticSeverity.Warning, 
@@ -55,7 +55,7 @@ public IEnumerable<DiagnosticRecord> AnalyzeScript(Ast ast, string fileName)
         /// <returns>The name of this rule</returns>
         public string GetName()
         {
-            return string.Format(CultureInfo.CurrentCulture, Strings.NameSpaceFormat, GetSourceName(), Strings.AvoidMultipleTypesParameterName);
+            return string.Format(CultureInfo.CurrentCulture, Strings.NameSpaceFormat, GetSourceName(), Strings.AvoidMultipleTypeAttributesName);
         }
 
         /// <summary>
@@ -64,7 +64,7 @@ public string GetName()
         /// <returns>The common name of this rule</returns>
         public string GetCommonName()
         {
-            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterCommonName);
+            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypeAttributesCommonName);
         }
 
         /// <summary>
@@ -73,7 +73,7 @@ public string GetCommonName()
         /// <returns>The description of this rule</returns>
         public string GetDescription()
         {
-            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypesParameterDescription);
+            return string.Format(CultureInfo.CurrentCulture, Strings.AvoidMultipleTypeAttributesDescription);
         }
 
         /// <summary>
diff --git a/Rules/Strings.Designer.cs b/Rules/Strings.Designer.cs
index bd212211b..9fead171c 100644
--- a/Rules/Strings.Designer.cs
+++ b/Rules/Strings.Designer.cs
@@ -466,38 +466,38 @@ internal static string AvoidLongLinesName {
         }
         
         /// <summary>
-        ///   Looks up a localized string similar to Avoid Multiple Types Parameter.
+        ///   Looks up a localized string similar to Avoid multiple type specifiers on parameters.
         /// </summary>
-        internal static string AvoidMultipleTypesParameterCommonName {
+        internal static string AvoidMultipleTypeAttributesCommonName {
             get {
-                return ResourceManager.GetString("AvoidMultipleTypesParameterCommonName", resourceCulture);
+                return ResourceManager.GetString("AvoidMultipleTypeAttributesCommonName", resourceCulture);
             }
         }
         
         /// <summary>
         ///   Looks up a localized string similar to Prameter should not have more than one type specifier..
         /// </summary>
-        internal static string AvoidMultipleTypesParameterDescription {
+        internal static string AvoidMultipleTypeAttributesDescription {
             get {
-                return ResourceManager.GetString("AvoidMultipleTypesParameterDescription", resourceCulture);
+                return ResourceManager.GetString("AvoidMultipleTypeAttributesDescription", resourceCulture);
             }
         }
         
         /// <summary>
         ///   Looks up a localized string similar to Parameter &apos;{0}&apos; has more than one type specifier..
         /// </summary>
-        internal static string AvoidMultipleTypesParameterError {
+        internal static string AvoidMultipleTypeAttributesError {
             get {
-                return ResourceManager.GetString("AvoidMultipleTypesParameterError", resourceCulture);
+                return ResourceManager.GetString("AvoidMultipleTypeAttributesError", resourceCulture);
             }
         }
         
         /// <summary>
-        ///   Looks up a localized string similar to AvoidMultipleTypesParameter.
+        ///   Looks up a localized string similar to AvoidMultipleTypeAttributes.
         /// </summary>
-        internal static string AvoidMultipleTypesParameterName {
+        internal static string AvoidMultipleTypeAttributesName {
             get {
-                return ResourceManager.GetString("AvoidMultipleTypesParameterName", resourceCulture);
+                return ResourceManager.GetString("AvoidMultipleTypeAttributesName", resourceCulture);
             }
         }
         
diff --git a/Rules/Strings.resx b/Rules/Strings.resx
index 5cb403af1..da1032671 100644
--- a/Rules/Strings.resx
+++ b/Rules/Strings.resx
@@ -1152,16 +1152,16 @@
   <data name="InvalidSyntaxAroundProcessBlockError" xml:space="preserve">
     <value>When using an explicit process block, no preceding code is allowed, only begin, end and dynamicparams blocks.</value>
   </data>
-  <data name="AvoidMultipleTypesParameterCommonName" xml:space="preserve">
+  <data name="AvoidMultipleTypeAttributesCommonName" xml:space="preserve">
     <value>Avoid multiple type specifiers on parameters</value>
   </data>
-  <data name="AvoidMultipleTypesParameterDescription" xml:space="preserve">
+  <data name="AvoidMultipleTypeAttributesDescription" xml:space="preserve">
     <value>Prameter should not have more than one type specifier.</value>
   </data>
-  <data name="AvoidMultipleTypesParameterError" xml:space="preserve">
+  <data name="AvoidMultipleTypeAttributesError" xml:space="preserve">
     <value>Parameter '{0}' has more than one type specifier.</value>
   </data>
-  <data name="AvoidMultipleTypesParameterName" xml:space="preserve">
-    <value>AvoidMultipleTypesParameter</value>
+  <data name="AvoidMultipleTypeAttributesName" xml:space="preserve">
+    <value>AvoidMultipleTypeAttributes</value>
   </data>
 </root>
diff --git a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1 b/Tests/Rules/AvoidMultipleTypeAttributes.tests.ps1
similarity index 95%
rename from Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
rename to Tests/Rules/AvoidMultipleTypeAttributes.tests.ps1
index fd3016fb4..5d448e64c 100644
--- a/Tests/Rules/AvoidMultipleTypesParameter.tests.ps1
+++ b/Tests/Rules/AvoidMultipleTypeAttributes.tests.ps1
@@ -2,14 +2,14 @@
 # Licensed under the MIT License.
 
 BeforeAll {
-    $ruleName = "PSAvoidMultipleTypesParameter"
+    $ruleName = "AvoidMultipleTypeAttributes"
 
     $settings = @{
         IncludeRules = @($ruleName)
     }
 }
 
-Describe 'AvoidMultipleTypesParameter' {
+Describe 'AvoidMultipleTypeAttributes' {
     It 'Correctly diagnoses and corrects <Script>' -TestCases @(
         @{ Script = 'function F1 ($s1, $p1){}' }
         @{ Script = 'function F2 ([int] $s2, [int] $p2){}' }