Add "OptionType should be Enum" to LinterCop

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/HasDiagnostic/OptionField.al

@@ -0,0 +1,13 @@
+table 50100 "My Table"
+{
+    fields
+    {
+        field(1; "Test Option"; [|Option|])
+        {
+            Caption = 'Test Option';
+            DataClassification = CustomerContent;
+            OptionCaption = '0,1,2,3,4,5';
+            OptionMembers = "0","1","2","3","4","5";
+        }    
+    }
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/HasDiagnostic/OptionParameterGlobalVar.al

@@ -0,0 +1,19 @@
+codeunit 50100 MyCodeunit
+{
+    var
+    [|Mode|]: Option "None","Allow deletion",Match;
+
+    procedure MyProcedure()
+    var
+        ReservationManagement: Codeunit "Reservation Management PTE";
+    begin
+        ReservationManagement.SetItemTrackingHandling(Mode);
+    end;
+}
+
+codeunit 50101 "Reservation Management PTE"
+{
+    procedure SetItemTrackingHandling(Mode: Option "None","Allow deletion",Match)
+    begin
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/HasDiagnostic/OptionParameterLocalVar.al

@@ -0,0 +1,17 @@
+codeunit 50100 MyCodeunit
+{
+    procedure MyProcedure()
+    var
+        ReservationManagement: Codeunit "Reservation Management PTE";
+        [|Mode|]: Option "None","Allow deletion",Match;
+    begin
+        ReservationManagement.SetItemTrackingHandling(Mode);
+    end;
+}
+
+codeunit 50101 "Reservation Management PTE"
+{
+    procedure SetItemTrackingHandling(Mode: Option "None","Allow deletion",Match)
+    begin
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/HasDiagnostic/OptionReturnValue.al

@@ -0,0 +1,7 @@
+codeunit 50100 MyCodeunit
+{
+    procedure MyProcedure() Mode: [|Option "None","Allow deletion",Match|]
+    begin
+
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/HasDiagnostic/OptionVariable.al

@@ -0,0 +1,14 @@
+codeunit 50100 MyCodeunit
+{
+    procedure MyProcedure([|TestOption: Option " ","Test1","Test2"|])
+    begin
+        case TestOption of
+            TestOption::" ":
+                exit;
+            TestOption::"Test1":
+                Message('test 1');
+            TestOption::"Test2":
+                Message('test 2');
+        end;
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/NoDiagnostic/CDSDocument.al

@@ -0,0 +1,37 @@
+table 50100 "Dataverse Project PTE"
+{
+    ExternalName = 'prefix_project';
+    TableType = CDS;
+    Description = '';
+    Caption = 'Project';
+
+    fields
+    {
+        field(1; prefix_projectId; Guid)
+        {
+            ExternalName = 'prefix_projectid';
+            ExternalType = 'Uniqueidentifier';
+            ExternalAccess = Insert;
+            Description = 'Unique identifier for entity instances';
+            Caption = 'Project';
+        }
+        field(2; prefix_name; Text[100])
+        {
+            ExternalName = 'prefix_name';
+            ExternalType = 'String';
+            Description = 'The name of the custom entity.';
+            Caption = 'Name';
+        }
+        field(25; statecode; [|Option|])
+        {
+            ExternalName = 'statecode';
+            ExternalType = 'State';
+            ExternalAccess = Modify;
+            Description = 'Status of the Project';
+            Caption = 'Status';
+            InitValue = " ";
+            OptionMembers = " ",Active,Inactive;
+            OptionOrdinalValues = -1, 0, 1;
+        }
+    }
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/NoDiagnostic/EventSubscriberOption.al

@@ -0,0 +1,23 @@
+codeunit 50100 MyCodeunit
+{
+    trigger OnRun()
+    var
+        OptionVariable: Option "", "test1";
+    begin
+        OnCodeunitRun(OptionVariable);
+    end;
+
+    [IntegrationEvent(false, false)]
+    local procedure OnCodeunitRun(var OptionVariable: Option "", "test1")
+    begin
+    end;
+}
+
+codeunit 50101 MySubscriber
+{
+    [EventSubscriber(ObjectType::Codeunit, Codeunit::MyCodeunit, OnCodeunitRun, '', false, false)]
+    local procedure OnCodeunitRun_MyCodeunit(var [|OptionVariable: Option "", "test1"|])
+    begin
+
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/NoDiagnostic/FlowField.al

@@ -0,0 +1,27 @@
+table 50100 MyTable
+{
+    fields
+    {
+        field(1; "No."; Code[20]) { }
+        field(2; "Warehouse Status"; [|Option|])
+        {
+            CalcFormula = min("My Warehouse Shipment Header"."Document Status" where("No." = field("No.")));
+            FieldClass = FlowField;
+            OptionMembers = " ","Partially Picked","Partially Shipped","Completely Picked","Completely Shipped";
+        }
+    }
+}
+
+table 50101 "My Warehouse Shipment Header"
+{
+    fields
+    {
+        field(1; "No."; Code[20]) { }
+        field(2; "Document Status"; Option)
+        {
+            OptionMembers = " ","Partially Picked","Partially Shipped","Completely Picked","Completely Shipped";
+        }
+    }
+}
+
+enum 50100 "Warehouse Status" { }

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/NoDiagnostic/ObsoleteFieldOption.al

@@ -0,0 +1,18 @@
+table 50100 "My Table"
+{
+    fields
+    {
+        field(1; MyField; Integer)
+        {
+            DataClassification = ToBeClassified;
+        }
+        field(2; "Test Option"; [|Option|])
+        {
+            Caption = 'Test Option';
+            ObsoleteState = Pending;
+            DataClassification = CustomerContent;
+            OptionCaption = '0,1,2,3,4,5';
+            OptionMembers = "0","1","2","3","4","5";
+        }    
+    }
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/NoDiagnostic/OptionParameter.al

@@ -0,0 +1,15 @@
+//TODO: Test with an codeunit from a dependency extension so the ."GetLocation().IsInSource" returns false
+codeunit 50100 MyCodeunit
+{
+    var
+        ModeGlobal: Option "None","Allow deletion",Match; // Should not raise a diagnostic
+
+    procedure MyProcedure()
+    var
+        ReservationManagement: Codeunit "Reservation Management";
+        ModeLocal: Option "None","Allow deletion",Match; // Should not raise a diagnostic
+    begin
+        ReservationManagement.SetItemTrackingHandling(ModeLocal);
+        ReservationManagement.SetItemTrackingHandling(ModeGlobal);
+    end;
+}

src/ALCops.LinterCop.Test/Rules/OptionTypeShouldBeEnum/OptionTypeShouldBeEnum.cs

@@ -0,0 +1,49 @@
+using RoslynTestKit;
+
+namespace ALCops.LinterCop.Test
+{
+    public class OptionTypeShouldBeEnum : NavCodeAnalysisBase
+    {
+        private AnalyzerTestFixture _fixture;
+        private string _testCasePath;
+
+        [SetUp]
+        public void Setup()
+        {
+            _fixture = RoslynFixtureFactory.Create<Analyzers.OptionTypeShouldBeEnum>();
+
+            _testCasePath = Path.Combine(
+                Directory.GetParent(
+                    Environment.CurrentDirectory)!.Parent!.Parent!.FullName,
+                    Path.Combine("Rules", nameof(OptionTypeShouldBeEnum)));
+        }
+
+        [Test]
+        [TestCase("OptionField")]
+        [TestCase("OptionParameterGlobalVar")]
+        [TestCase("OptionParameterLocalVar")]
+        [TestCase("OptionReturnValue")]
+        [TestCase("OptionVariable")]
+        public async Task HasDiagnostic(string testCase)
+        {
+            var code = await File.ReadAllTextAsync(Path.Combine(_testCasePath, nameof(HasDiagnostic), $"{testCase}.al"))
+                .ConfigureAwait(false);
+
+            _fixture.HasDiagnosticAtAllMarkers(code, DiagnosticIds.OptionTypeShouldBeEnum);
+        }
+
+        [Test]
+        [TestCase("CDSDocument")]
+        [TestCase("EventSubscriberOption")]
+        [TestCase("FlowField")]
+        [TestCase("ObsoleteFieldOption")]
+        // [TestCase("OptionParameter")] //TODO: See remarks in the test file
+        public async Task NoDiagnostic(string testCase)
+        {
+            var code = await File.ReadAllTextAsync(Path.Combine(_testCasePath, nameof(NoDiagnostic), $"{testCase}.al"))
+                .ConfigureAwait(false);
+
+            _fixture.NoDiagnosticAtAllMarkers(code, DiagnosticIds.OptionTypeShouldBeEnum);
+        }
+    }
+}

src/ALCops.LinterCop/ALCops.LinterCopAnalyzers.cs

@@ -615,6 +615,33 @@ internal static string ObjectIdInDeclarationTitle {
             }
         }
 
+        /// <summary>
+        ///   Looks up a localized string similar to Enums are preferred over Option types because they provide stronger typing, better extensibility, and clearer intent. Using Enums reduces error-prone patterns commonly associated with Option fields and improves maintainability and versioning of AL code..
+        /// </summary>
+        internal static string OptionTypeShouldBeEnumDescription {
+            get {
+                return ResourceManager.GetString("OptionTypeShouldBeEnumDescription", resourceCulture);
+            }
+        }
+
+        /// <summary>
+        ///   Looks up a localized string similar to Prefer using an Enum instead of an Option type..
+        /// </summary>
+        internal static string OptionTypeShouldBeEnumMessageFormat {
+            get {
+                return ResourceManager.GetString("OptionTypeShouldBeEnumMessageFormat", resourceCulture);
+            }
+        }
+
+        /// <summary>
+        ///   Looks up a localized string similar to Prefer Enum over Option type.
+        /// </summary>
+        internal static string OptionTypeShouldBeEnumTitle {
+            get {
+                return ResourceManager.GetString("OptionTypeShouldBeEnumTitle", resourceCulture);
+            }
+        }
+
         /// <summary>
         ///   Looks up a localized string similar to Adopting the use of the new PageStyle datatype allows to more easily get the supported pagestyles via IntelliSense and avoids incorrect behaviour when a typo is made in hardcoded strings or label variables..
         /// </summary>

src/ALCops.LinterCop/ALCops.LinterCopAnalyzers.resx

@@ -306,6 +306,15 @@
   <data name="ObjectIdInDeclarationActionTitle" xml:space="preserve">
     <value>ALCops: Replace id with name of object reference</value>
   </data>
+  <data name="OptionTypeShouldBeEnumTitle" xml:space="preserve">
+    <value>Prefer Enum over Option type</value>
+  </data>
+  <data name="OptionTypeShouldBeEnumMessageFormat" xml:space="preserve">
+    <value>Prefer using an Enum instead of an Option type.</value>
+  </data>
+  <data name="OptionTypeShouldBeEnumDescription" xml:space="preserve">
+    <value>Enums are preferred over Option types because they provide stronger typing, better extensibility, and clearer intent. Using Enums reduces error-prone patterns commonly associated with Option fields and improves maintainability and versioning of AL code.</value>
+  </data>
   <data name="PageStyleStringLiteralTitle" xml:space="preserve">
     <value>Use the new PageStyle datatype instead string literals</value>
   </data>