Fix Configuration::to_json always emitting path and baseUri (#628)

Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

Author: jviotti

src/configuration/json.cc

@@ -32,9 +32,14 @@ auto Configuration::to_json() const -> sourcemeta::core::JSON {
     result.assign("website", sourcemeta::core::JSON{this->website.value()});
   }
 
-  result.assign("path",
-                sourcemeta::core::JSON{this->absolute_path.generic_string()});
-  result.assign("baseUri", sourcemeta::core::JSON{this->base});
+  if (!this->absolute_path.empty()) {
+    result.assign("path",
+                  sourcemeta::core::JSON{this->absolute_path.generic_string()});
+  }
+
+  if (!this->base.empty()) {
+    result.assign("baseUri", sourcemeta::core::JSON{this->base});
+  }
 
   if (this->default_dialect.has_value()) {
     result.assign("defaultDialect",

test/configuration/configuration_json_test.cc

@@ -128,6 +128,16 @@ TEST(Configuration_json, to_json_minimal) {
   EXPECT_EQ(result, expected);
 }
 
+TEST(Configuration_json, to_json_empty) {
+  sourcemeta::blaze::Configuration config;
+
+  const auto result{config.to_json()};
+
+  const auto expected{sourcemeta::core::parse_json(R"JSON({})JSON")};
+
+  EXPECT_EQ(result, expected);
+}
+
 TEST(Configuration_json, to_json_with_extra) {
   sourcemeta::blaze::Configuration config;
   config.absolute_path = "/test";