Fix static being applied to classes without static methods/fields

Author: duckdoom5

src/Generator.Tests/Passes/TestPasses.cs

@@ -73,11 +73,13 @@ public void TestCheckStaticClassPass()
             var staticStruct = AstContext.Class("TestCheckStaticStruct");
             var staticClassDeletedCtor = AstContext.Class("TestCheckStaticClassDeleted");
             var nonStaticClass = AstContext.Class("TestCheckNonStaticClass");
+            var nonStaticEmptyClass = AstContext.Class("TestCommentsPass");
 
             Assert.IsFalse(staticClass.IsStatic);
             Assert.IsFalse(staticStruct.IsStatic);
             Assert.IsFalse(staticClassDeletedCtor.IsStatic);
             Assert.IsFalse(nonStaticClass.IsStatic);
+            Assert.IsFalse(nonStaticEmptyClass.IsStatic);
 
             passBuilder.AddPass(new CheckStaticClassPass());
             passBuilder.RunPasses(pass => pass.VisitASTContext(AstContext));
@@ -87,6 +89,7 @@ public void TestCheckStaticClassPass()
             Assert.IsTrue(staticClassDeletedCtor.IsStatic, "`TestCheckStaticClassDeleted` should be static");
 
             Assert.IsFalse(nonStaticClass.IsStatic, "`TestCheckNonStaticClass` should NOT be static, since it has a private data field with default ctor");
+            Assert.IsFalse(nonStaticEmptyClass.IsStatic, "`TestCommentsPass` should NOT be static, since it doesn't have any static declarations");
         }
 
         [Test]

src/Generator/Passes/CheckStaticClassPass.cs

@@ -77,6 +77,25 @@ public override bool VisitClassDecl(Class @class)
             if (@class.IsDependent)
                 return false;
 
+            // Polymorphic classes are currently not supported.
+            // TODO: We could support this if the base class is also static, since it's composition then.
+            if (@class.IsPolymorphic)
+                return false;
+
+            // Make sure we have at least one accessible static method or field
+            if (!@class.Methods.Any(m => m.Kind == CXXMethodKind.Normal && m.Access != AccessSpecifier.Private && m.IsStatic)
+                && @class.Variables.All(v => v.Access == AccessSpecifier.Private))
+                return false;
+
+            // Check for any non-static fields or methods, in which case we
+            // assume the class is not meant to be static.
+            // Note: Static fields are represented as variables in the AST.
+            if (@class.Fields.Count != 0)
+                return false;
+
+            if (@class.Methods.Any(m => m.Kind == CXXMethodKind.Normal && !m.IsStatic))
+                return false;
+
             if (@class.Constructors.Any(m =>
                 {
                     // Implicit constructors are not user-defined, so assume this was unintentional.
@@ -97,13 +116,6 @@ public override bool VisitClassDecl(Class @class)
             {
                 return false;
             }
-            // Check for any non-static fields or methods, in which case we
-            // assume the class is not meant to be static.
-            // Note: Static fields are represented as variables in the AST.
-            if (@class.Fields.Any() ||
-                @class.Methods.Any(m => m.Kind == CXXMethodKind.Normal
-                && !m.IsStatic))
-                return false;
 
             // Check for any static function that return a pointer to the class.
             // If one exists, we assume it's a factory function and the class is