Fixed stupid issue where types would be treated as matches for the re…

…adonly generator even if they didn't have the right attribute.

Schema Tests/readOnly/ReadOnlyReferenceTests.cs

@@ -343,5 +343,51 @@ public interface IReadOnlyWrapper<T> {
 
           """);
     }
+
+    [Test]
+    public void TestIgnoresFakeMatches() {
+      ReadOnlyGeneratorTestUtil.AssertGenerated(
+          """
+          using schema.readOnly;
+          using foo.bar.correct;
+          using foo.bar.wrong;
+
+          namespace foo.bar.correct {
+            public class Other;
+          }
+
+          namespace foo.bar.correct {
+            [GenerateReadOnly]
+            public partial interface IOther;
+          }
+
+          namespace foo.bar {
+            [GenerateReadOnly]
+            public partial interface IWrapper {
+              IReadOnlyOther Field { get; set; }
+            }
+          }
+          """,
+          """
+          namespace foo.bar.correct {
+            public partial interface IOther : IReadOnlyOther;
+
+            public interface IReadOnlyOther;
+          }
+
+          """,
+          """
+          namespace foo.bar {
+            public partial interface IWrapper : IReadOnlyWrapper {
+              correct.IReadOnlyOther IReadOnlyWrapper.Field => Field;
+            }
+
+            public interface IReadOnlyWrapper {
+              public correct.IReadOnlyOther Field { get; }
+            }
+          }
+
+          """);
+    }
   }
 }

Schema/src/readOnly/ReadOnlyTypeGenerator.cs

@@ -604,6 +604,7 @@ public static IEnumerable<INamedTypeSymbol> LookupTypesWithNameAndArity(
         int arity)
       => semanticModel
          .LookupNamespacesAndTypes(syntax.SpanStart, null, searchString)
+         .Where(symbol => symbol.HasAttribute<GenerateReadOnlyAttribute>())
          .Where(symbol => symbol is INamedTypeSymbol)
          .Select(symbol => symbol as INamedTypeSymbol)
          .Where(symbol => symbol.Arity == arity);