[infra] Support unit-testing via GTest

.github/workflows/hsim.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        path: ['src', 'include']
+        path: ['src', 'include', 'test']
     steps:
       - name: Checkout repo and submodules
         uses: actions/checkout@v4

CMakeLists.txt

@@ -28,3 +28,6 @@ add_executable(${PROJECT_NAME} src/main.cc)
 target_compile_options(${PROJECT_NAME} PRIVATE -Wpedantic)
 target_link_libraries(${PROJECT_NAME} PRIVATE hSim-lib CLI11::CLI11 fmt::fmt)
 set_target_properties(${PROJECT_NAME} PROPERTIES OUTPUT_NAME hsim)
+
+enable_testing()
+add_subdirectory(test)

test/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory(unit)

test/unit/CMakeLists.txt

@@ -0,0 +1,20 @@
+include(GoogleTest)
+
+# Helpful macro to add unittest
+# Accepts src_file (with utest) as mandatory argument
+# and list of linked libraries after it
+macro(hsim_add_utest src_file)
+  set(TEST_NAME "${src_file}_test")
+  add_executable(${TEST_NAME} ${src_file})
+
+  target_link_libraries(${TEST_NAME} PRIVATE GTest::gtest_main hSIM::defaults)
+  foreach(arg IN LISTS ARGN)
+    target_link_libraries(${TEST_NAME} PRIVATE ${arg})
+  endforeach()
+  gtest_discover_tests(
+    ${TEST_NAME}
+    EXTRA_ARGS --gtest_color=yes
+    PROPERTIES LABELS unit)
+endmacro()
+
+add_subdirectory(hello)

test/unit/hello/CMakeLists.txt

@@ -0,0 +1 @@
+hsim_add_utest(hello.cc)

test/unit/hello/hello.cc

@@ -0,0 +1,3 @@
+#include <gtest/gtest.h>
+
+TEST(Simple, Hello) { ASSERT_TRUE(true); }

third_party/CMakeLists.txt

@@ -21,3 +21,17 @@ CPMAddPackage(
   GIT_TAG Release_3.12
   EXCLUDE_FROM_ALL True
   SYSTEM True)
+
+
+# gtest
+CPMAddPackage(
+  NAME
+  googletest
+  GITHUB_REPOSITORY
+  google/googletest
+  VERSION
+  1.16.0
+  OPTIONS
+  "INSTALL_GTEST OFF"
+  EXCLUDE_FROM_ALL True
+  SYSTEM True)