cmake: build math_opt elemental C++ tests

* add test to elemental_test.cc

Author: Mizux

ortools/math_opt/elemental/CMakeLists.txt

@@ -28,3 +28,43 @@ target_link_libraries(${NAME} PRIVATE
   ${PROJECT_NAMESPACE}::math_opt_proto
   absl::strings
 )
+
+ortools_cxx_library(
+  NAME
+    math_opt_elemental_matcher
+  SOURCES
+    "elemental_matcher.cc"
+    "elemental_matcher.h"
+  TYPE
+    STATIC
+  LINK_LIBRARIES
+    absl::log
+    absl::status
+    absl::strings
+    GTest::gmock
+  TESTING
+)
+
+if(BUILD_TESTING)
+  file(GLOB _TEST_SRCS "*_test.cc")
+  list(FILTER _TEST_SRCS
+    EXCLUDE REGEX "elemental_export_model_update_test.cc$")
+  list(FILTER _TEST_SRCS
+    EXCLUDE REGEX "elemental_from_proto_fuzz_test.cc$") # need fuzztest
+  foreach(_FULL_FILE_NAME IN LISTS _TEST_SRCS)
+    get_filename_component(_NAME ${_FULL_FILE_NAME} NAME_WE)
+    get_filename_component(_FILE_NAME ${_FULL_FILE_NAME} NAME)
+    ortools_cxx_test(
+      NAME
+        math_opt_elemental_${_NAME}
+      SOURCES
+        ${_FILE_NAME}
+      LINK_LIBRARIES
+        benchmark::benchmark
+        GTest::gmock
+        GTest::gtest_main
+        ortools::math_opt_matchers
+        ortools::math_opt_elemental_matcher
+    )
+  endforeach()
+endif()

ortools/math_opt/elemental/elemental_test.cc

@@ -453,6 +453,28 @@ TEST(ElementalTest, Attr2RespondsToElementDeletionKey1) {
   EXPECT_THAT(elemental.AttrNonDefaults(DoubleAttr2::kLinConCoef), IsEmpty());
 }
 
+TEST(ElementalTest, SymmetricAttr2) {
+  using Key = AttrKeyFor<SymmetricDoubleAttr2>;
+  Elemental elemental;
+  const VariableId x0 = elemental.AddElement<ElementType::kVariable>("x1");
+  const VariableId x1 = elemental.AddElement<ElementType::kVariable>("x2");
+  const VariableId x2 = elemental.AddElement<ElementType::kVariable>("x3");
+
+  const auto q01 = Key(x0, x1);
+  const auto q21 = Key(x2, x1);
+  const auto q12 = Key(x1, x2);
+
+  elemental.SetAttr(SymmetricDoubleAttr2::kObjQuadCoef, q01, 42.0);
+  elemental.SetAttr(SymmetricDoubleAttr2::kObjQuadCoef, q21, 43.0);
+  elemental.SetAttr(SymmetricDoubleAttr2::kObjQuadCoef, q12, 44.0);
+
+  EXPECT_EQ(elemental.AttrNumNonDefaults(SymmetricDoubleAttr2::kObjQuadCoef),
+            2);
+
+  EXPECT_THAT(elemental.AttrNonDefaults(SymmetricDoubleAttr2::kObjQuadCoef),
+              UnorderedElementsAre(q01, q12));
+}
+
 TEST(ElementalTest, SymmetricAttr2RespondsToElementDeletionKey0) {
   using Key = AttrKeyFor<SymmetricDoubleAttr2>;
   Elemental elemental;