Add filtering option for add_database (#19)

Author: DefaultRyan

src/impl/winmd_reader/cache.h

@@ -158,12 +158,13 @@ namespace winmd::reader
 
         // This won't invalidate any existing database or row_base (e.g. TypeDef) instances
         // However, it may invalidate iterators and references to namespace_members, because those are stored in std::vector
-        void add_database(std::string_view const& file)
+        template <typename TypeFilter>
+        void add_database(std::string_view const& file, TypeFilter filter)
         {
             auto& db = m_databases.emplace_back(file, this);
             for (auto&& type : db.TypeDef)
             {
-                if (type.Flags().value == 0 || is_nested(type))
+                if (type.Flags().value == 0 || is_nested(type) || !filter(type))
                 {
                     continue;
                 }
@@ -182,6 +183,11 @@ namespace winmd::reader
             }
         }
 
+        void add_database(std::string_view const& file)
+        {
+            add_database(file, default_type_filter{});
+        }
+
         std::vector<TypeDef> const& nested_types(TypeDef const& enclosing_type) const
         {
             auto it = m_nested_types.find(enclosing_type);

test/cache.cpp

@@ -60,6 +60,32 @@ TEST_CASE("cache_add")
     REQUIRE(JsonValue.TypeNamespace() == "Windows.Data.Json");
 }
 
+TEST_CASE("cache_add_filter")
+{
+    std::filesystem::path winmd_dir = get_local_winmd_path();
+    auto file_path = winmd_dir;
+    file_path.append("Windows.Foundation.winmd");
+
+    cache c(file_path.string());
+
+    TypeDef JsonValue = c.find("Windows.Data.Json", "JsonValue");
+    REQUIRE(!JsonValue);
+
+    file_path = winmd_dir;
+    file_path.append("Windows.Data.winmd");
+    c.add_database(file_path.string(), [](TypeDef const& type)
+        {
+            return !(type.TypeNamespace() == "Windows.Data.Json" && type.TypeName() == "JsonArray");
+        });
+
+    JsonValue = c.find("Windows.Data.Json", "JsonValue");
+    REQUIRE(!!JsonValue);
+    REQUIRE(JsonValue.TypeName() == "JsonValue");
+    REQUIRE(JsonValue.TypeNamespace() == "Windows.Data.Json");
+
+    REQUIRE(!c.find("Windows.Data.Json", "JsonArray"));
+}
+
 TEST_CASE("cache_add_duplicate")
 {
     std::filesystem::path winmd_dir = get_local_winmd_path();