Add automated testing using doctest (microsoft#55)

* Add automated testing using doctest

This change adds basic unit testing for some simple scenarios in the IFC.

* Added [`doctest`](https://github.com/doctest/doctest) as a dependency for unit testing the C++ SDK.
* Added preset value for building the testing executables.
* Added unit tests for MSVC.
* Improved documentation for building in developer mode.

BUILDING.md

@@ -49,6 +49,38 @@ cmake --build build --config Release
 
 If you are using vcpkg as your C++ package manager, you might need to add `-DCMAKE_TOOLCHAIN_FILE=<path-to-your-vcpkd-root>/scripts/buildsystems/vcpkg.cmake` to the CMake command in the configuration step.
 
+### Unit Testing
+
+For configuring with testing enabled (only MSVC is enabled for now):
+
+```sh
+cmake -B build --preset=test-msvc
+cmake --build build/test
+cd build
+ctest -C debug test
+```
+
+### Using vcpkg (for testing)
+
+This project depends on [`doctest`](https://github.com/doctest/doctest) for validating the SDK.  We recommend using [`vcpkg`](https://vcpkg.io) for managing this dependency.  This project does not provide a [`builtin-baseline`](https://learn.microsoft.com/en-us/vcpkg/reference/vcpkg-json#builtin-baseline) in the `vcpkg.json` intentionally so that system dependencies can be relied on.  If you are not using `vcpkg` in [classic mode](https://learn.microsoft.com/en-us/vcpkg/users/classic-mode) then you must introduce your own baseline (either through [`vcpkg x-update-baseline`](https://learn.microsoft.com/en-us/vcpkg/commands/update-baseline)) or add a custom [`vcpkg-configuration.json`](https://learn.microsoft.com/en-us/vcpkg/reference/vcpkg-configuration-json).  Here's an example of using the `x-update-baseline` method:
+
+```sh
+vcpkg x-update-baseline --add-initial-baseline
+cmake -B build -DCMAKE_TOOLCHAIN_FILE=<path-to>/vcpkg.cmake --preset=test-msvc
+```
+
+Note: Using this method will locally modify `/vcpkg.json` so be sure to revert it or exclude it from your commit before submitting any change for PR.
+
+On Linux platforms please consult your package manager for alternative distributions of the C++ `doctest` framework.  Some common alternatives:
+
+- arch: `doctest`
+- debian: `doctest-dev`
+- fedora: `doctest`
+- gentoo: `dev-cpp/doctest`
+- ubuntu: `doctest-dev`
+
+When using an alternative source for packages be sure to consult your distribution documentation on how to make that package available for CMake.
+
 ## Install
 
 Here is the command for installing the release mode artifacts with a

CMakePresets.json

@@ -119,6 +119,10 @@
     {
       "name": "ci-windows",
       "inherits": ["ci-build", "ci-win64", "dev-mode", "vcpkg", "vcpkg-win64-static"]
+    },
+    {
+      "name": "test-msvc",
+      "inherits": ["ci-build", "ci-win64", "dev-mode", "vcpkg", "vcpkg-win64-static"]
     }
   ]
 }

README.md

@@ -27,6 +27,8 @@ This will create an IFC file named test.cpp.ifc. This can be dumped with ifc-pri
 ifc-printer.exe --color test.cpp.ifc
 ```
 
+See [BUILDING.md](BUILDING.md) for more information.
+
 # Contributing
 This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to grant us the right to use your contribution. For details, visit https://cla.opensource.microsoft.com.
 
@@ -56,4 +58,4 @@ Resources:
 
 Copyright (c) Microsoft Corporation.
 
-SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

cmake/find/FindMicrosoft.GSL.cmake

@@ -2,7 +2,7 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 # This module is an opt-in find module _only_ for developers of the SDK who
-# wish not to use vcpkg. To tell CMake about this find module, pass this file's
+# cannot use vcpkg. To tell CMake about this find module, pass this file's
 # directory via the CMAKE_MODULE_PATH command line option. This will satisfy a
 # simple find_package(Microsoft.GSL REQUIRED) call by default.
 # Do not use for release builds, because the GSL targets will also be added to

cmake/find/Finddoctest.cmake

@@ -0,0 +1,20 @@
+# Copyright Microsoft Corporation.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# This module is an opt-in find module _only_ for developers of the SDK who
+# cannot use vcpkg. To tell CMake about this find module, pass this file's
+# directory via the CMAKE_MODULE_PATH command line option. This will satisfy a
+# simple find_package(doctest REQUIRED) call by default.
+
+include(FetchContent)
+
+FetchContent_Declare(
+    doctest
+    GIT_REPOSITORY https://github.com/doctest/doctest.git
+    GIT_TAG v2.4.11
+    GIT_SHALLOW YES
+)
+
+FetchContent_MakeAvailable(doctest)
+
+set(doctest_FOUND 1)

test/CMakeLists.txt

@@ -9,9 +9,44 @@ if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   find_package(Microsoft.IFC REQUIRED)
 endif()
 
+find_package(doctest CONFIG REQUIRED)
+
 add_executable(ifc-test main.cxx)
+
+target_compile_features(ifc-test PRIVATE cxx_std_23)
+
+# Libs for ifc-test
 target_link_libraries(ifc-test PRIVATE Microsoft.IFC::SDK)
 
+if (WIN32)
+  # Only enabled for MSVC for now.
+  add_executable(ifc-basic basic.cxx)
+  # MSVC-specific testing
+  # Test IFCs
+  add_custom_target(test-ifcs
+    COMMAND
+      ${CMAKE_CXX_COMPILER}
+      /nologo
+      /std:c++20
+      /ifcOutput${CMAKE_BINARY_DIR}/m.ifc
+      /c
+      ${CMAKE_CURRENT_SOURCE_DIR}/m.ixx)
+
+  add_dependencies(ifc-basic test-ifcs)
+
+  target_compile_features(ifc-basic PRIVATE cxx_std_23)
+
+  target_compile_definitions(ifc-basic PRIVATE IFC_FILE="${CMAKE_BINARY_DIR}/m.ifc")
+
+  # Libs for ifc-basic
+  target_link_libraries(ifc-basic PRIVATE Microsoft.IFC::SDK)
+  target_link_libraries(ifc-basic PRIVATE doctest::doctest)
+endif()
+
 enable_testing()
 
 add_test(NAME ifc-test COMMAND ifc-test)
+
+if (WIN32)
+  add_test(NAME ifc-basic COMMAND ifc-basic)
+endif()