Merge pull request #648 from SteveDunn/interface-generation

Add ability to switch off generating IVogen interface but still derive from it

src/Vogen.SharedTypes/StaticAbstractsGeneration.cs

@@ -13,7 +13,7 @@ public enum StaticAbstractsGeneration
     Unspecified = -1,
 
     /// <summary>
-    /// Do not generate the factory.
+    /// Do not generate the interface definition, nor make the value objects derive implement the interface.
     /// </summary>
     Omit = 0,
 
@@ -53,9 +53,17 @@ public enum StaticAbstractsGeneration
     InstanceMethodsAndProperties = 1 << 6,
 
     /// <summary>
-    /// The most common usage; generates equals, explicit casts, and factory methods.
+    /// Value objects that are generated derive from `: IVogen`. Use just this flag if you have several projects and only wish to
+    /// generate the definition in one of them, or if you want to define it yourself.
     /// </summary>
-    MostCommon = EqualsOperators |
+    ValueObjectsDeriveFromTheInterface = 1 << 7,
+
+    /// <summary>
+    /// The most common usage; generates the definition, containing equals, explicit casts, and factory methods, and
+    /// make value objects derive from it.
+    /// </summary>
+    MostCommon = ValueObjectsDeriveFromTheInterface |
+                 EqualsOperators |
                  ExplicitCastFromPrimitive |
                  ExplicitCastToPrimitive |
                  FactoryMethods

src/Vogen/WriteStaticAbstracts.cs

@@ -19,7 +19,8 @@ public static void WriteInterfacesAndMethodsIfNeeded(VogenConfiguration? globalC
         StaticAbstractsGeneration generation = globalConfig?.StaticAbstractsGeneration ??
                                                VogenConfiguration.DefaultInstance.StaticAbstractsGeneration;
 
-        if (generation == StaticAbstractsGeneration.Omit)
+        // we don't want to generate if omitting or if we're only _using_ the interface (it could be declared somewhere else)
+        if (generation is StaticAbstractsGeneration.Omit or StaticAbstractsGeneration.ValueObjectsDeriveFromTheInterface)
         {
             return;
         }
@@ -127,16 +128,16 @@ string GenerateEqualsOperatorsIfNeeded()
 
     public static string WriteHeaderIfNeeded(string precedingText, VoWorkItem item, TypeDeclarationSyntax tds)
     {
-        if (item.Config.StaticAbstractsGeneration == StaticAbstractsGeneration.Omit)
+        if (item.LanguageVersion < LanguageVersion.CSharp11)
         {
             return string.Empty;
         }
 
-        if (item.LanguageVersion >= LanguageVersion.CSharp11)
+        if (!item.Config.StaticAbstractsGeneration.HasFlag(StaticAbstractsGeneration.ValueObjectsDeriveFromTheInterface))
         {
-            return precedingText + $" IVogen<{tds.Identifier}, {item.UnderlyingTypeFullName}>";
+            return string.Empty;
         }
 
-        return string.Empty;
+        return precedingText + $" IVogen<{tds.Identifier}, {item.UnderlyingTypeFullName}>";
     }
 }

tests/SnapshotTests/StaticAbstracts/StaticAbstractTests.cs

@@ -142,12 +142,12 @@ public partial {{type}} MyVo { }
     }
 
     [Theory]
-    [InlineData("EqualsOperators")]
-    [InlineData("FactoryMethods")]
-    [InlineData("EqualsOperators", "FactoryMethods")]
-    [InlineData("InstanceMethodsAndProperties")]
-    [InlineData("InstanceMethodsAndProperties", "EqualsOperators", "FactoryMethods")]
-    [InlineData("InstanceMethodsAndProperties", "FactoryMethods", "EqualsOperators")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "EqualsOperators")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "FactoryMethods")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "EqualsOperators", "FactoryMethods")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "InstanceMethodsAndProperties")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "InstanceMethodsAndProperties", "EqualsOperators", "FactoryMethods")]
+    [InlineData("ValueObjectsDeriveFromTheInterface", "InstanceMethodsAndProperties", "FactoryMethods", "EqualsOperators")]
     public async Task Generates_code_for_different_variations(params string[] flags)
     {
         string attrs = string.Join(" | ", flags.Select(f => $"StaticAbstractsGeneration.{f}"));

tests/SnapshotTests/StaticAbstracts/snapshots/snap-v8.0/StaticAbstractTests.when_using_implicit_operators.verified.txt

@@ -79,7 +79,7 @@ using Vogen;
 
     [global::System.Diagnostics.DebuggerTypeProxyAttribute(typeof(MyVoDebugView))]
     [global::System.Diagnostics.DebuggerDisplayAttribute("Underlying type: System.Guid, Value = { _value }")]
-    public partial class MyVo : global::System.IEquatable<MyVo>, global::System.IEquatable<System.Guid> ,  global::System.IComparable<MyVo>, global::System.IComparable,  global::System.IParsable<MyVo>,  global::System.ISpanParsable<MyVo>,  IVogen<MyVo, System.Guid>
+    public partial class MyVo : global::System.IEquatable<MyVo>, global::System.IEquatable<System.Guid> ,  global::System.IComparable<MyVo>, global::System.IComparable,  global::System.IParsable<MyVo>,  global::System.ISpanParsable<MyVo>
     {
 #if DEBUG   
         private readonly global::System.Diagnostics.StackTrace _stackTrace = null;