Add "make check" target to build and run tests

CTest already provides a "make test" target, but this only runs previously
built tests.

Also in this commit:

- Move all test code and build rules to a new test/ subdirectory to separate
  test code from non-test code
- Add a new "make tests" target used internally by "make check" to build tests
  without running them

CMakeLists.txt

@@ -5,7 +5,6 @@
 cmake_minimum_required(VERSION 3.0)
 project("Libmultiprocess" CXX)
 include(CMakePushCheckState)
-include(CTest)
 include(CheckCXXSourceCompiles)
 find_package(CapnProto REQUIRED)
 find_package(Threads REQUIRED)
@@ -92,48 +91,4 @@ install(FILES "include/mpgen.mk" DESTINATION "include")
 
 install(EXPORT Multiprocess DESTINATION lib/cmake/Multiprocess)
 
-if(BUILD_TESTING AND TARGET CapnProto::kj-test)
-  add_custom_command(
-    OUTPUT
-      src/mp/test/foo.capnp.h
-      src/mp/test/foo.capnp.c++
-      src/mp/test/foo.capnp.proxy.h
-      src/mp/test/foo.capnp.proxy-server.c++
-      src/mp/test/foo.capnp.proxy-client.c++
-      src/mp/test/foo.capnp.proxy-types.c++
-      src/mp/test/foo.capnp.proxy-types.h
-    COMMAND mpgen "${CMAKE_CURRENT_SOURCE_DIR}" "${CMAKE_CURRENT_SOURCE_DIR}/src" "${CMAKE_CURRENT_SOURCE_DIR}/src/mp/test/foo.capnp" "${CMAKE_CURRENT_SOURCE_DIR}/include" "${capnp_PREFIX}/include"
-    DEPENDS src/mp/test/foo.capnp mpgen
-  )
-  add_executable(mptest EXCLUDE_FROM_ALL
-    ${MP_PROXY_HDRS}
-    src/mp/test/foo.capnp.h
-    src/mp/test/foo.capnp.c++
-    src/mp/test/foo.capnp.proxy.h
-    src/mp/test/foo.capnp.proxy-server.c++
-    src/mp/test/foo.capnp.proxy-client.c++
-    src/mp/test/foo.capnp.proxy-types.c++
-    src/mp/test/foo.capnp.proxy-types.h
-    src/mp/test/foo-types.h
-    src/mp/test/foo.h
-    src/mp/test/test.cpp
-  )
-  target_include_directories(mptest PUBLIC
-    ${CAPNP_INCLUDE_DIRECTORY}
-    $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>
-    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
-    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
-    $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/src>
-  )
-  target_link_libraries(mptest PRIVATE CapnProto::capnp)
-  target_link_libraries(mptest PRIVATE CapnProto::capnp-rpc)
-  target_link_libraries(mptest PRIVATE CapnProto::kj)
-  target_link_libraries(mptest PRIVATE CapnProto::kj-async)
-  target_link_libraries(mptest PRIVATE CapnProto::kj-test)
-  target_link_libraries(mptest PRIVATE Threads::Threads)
-  target_link_libraries(mptest PRIVATE multiprocess)
-  set_target_properties(mptest PROPERTIES
-    CXX_STANDARD 17
-    CXX_STANDARD_REQUIRED YES)
-  add_test(NAME mptest COMMAND mptest)
-endif()
+add_subdirectory(test EXCLUDE_FROM_ALL)

README.md

@@ -19,7 +19,7 @@ There is also optional support for thread mapping, so each thread making interpr
 
 ## Example
 
-A simple interface description can be found at [src/mp/test/foo.capnp](src/mp/test/foo.capnp), implementation in [src/mp/test/foo.h](src/mp/test/foo.h), and usage in [src/mp/test/test.cpp](src/mp/test/test.cpp).
+A simple interface description can be found at [test/src/mp/test/foo.capnp](test/src/mp/test/foo.capnp), implementation in [test/src/mp/test/foo.h](test/src/mp/test/foo.h), and usage in [test/src/mp/test/test.cpp](test/src/mp/test/test.cpp).
 
 ## Future directions
 
@@ -44,6 +44,6 @@ mkdir build
 cd build
 cmake ..
 make
-make all test
+make check # Optionally build and run tests
 make install
 ```

test/CMakeLists.txt

@@ -0,0 +1,66 @@
+# Copyright (c) 2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+include(CTest)
+
+# Custom test targets for convenience, based on
+# https://gitlab.kitware.com/cmake/community/-/wikis/doc/tutorials/EmulateMakeCheck.
+#
+# CTest already provides a "make test" target, but it just runs existing tests
+# that were previously built, without building anything itself. Define "make
+# tests" here as a custom target to build all available tests and "make check"
+# as a custom target to build and run them.
+add_custom_target(tests DEPENDS mptest)
+add_custom_target(check COMMAND ${CMAKE_CTEST_COMMAND} DEPENDS tests)
+
+if(BUILD_TESTING AND TARGET CapnProto::kj-test)
+  add_custom_command(
+    OUTPUT
+      src/mp/test/foo.capnp.h
+      src/mp/test/foo.capnp.c++
+      src/mp/test/foo.capnp.proxy.h
+      src/mp/test/foo.capnp.proxy-server.c++
+      src/mp/test/foo.capnp.proxy-client.c++
+      src/mp/test/foo.capnp.proxy-types.c++
+      src/mp/test/foo.capnp.proxy-types.h
+    COMMAND mpgen "${CMAKE_CURRENT_SOURCE_DIR}" "${CMAKE_CURRENT_SOURCE_DIR}/src" "${CMAKE_CURRENT_SOURCE_DIR}/src/mp/test/foo.capnp" "${CMAKE_SOURCE_DIR}/include" "${capnp_PREFIX}/include"
+    DEPENDS src/mp/test/foo.capnp mpgen
+  )
+
+  set_property(SOURCE ${MP_PROXY_HDRS} PROPERTY GENERATED 1)
+
+  add_executable(mptest
+    ${MP_PROXY_HDRS}
+    src/mp/test/foo.capnp.h
+    src/mp/test/foo.capnp.c++
+    src/mp/test/foo.capnp.proxy.h
+    src/mp/test/foo.capnp.proxy-server.c++
+    src/mp/test/foo.capnp.proxy-client.c++
+    src/mp/test/foo.capnp.proxy-types.c++
+    src/mp/test/foo.capnp.proxy-types.h
+    src/mp/test/foo-types.h
+    src/mp/test/foo.h
+    src/mp/test/test.cpp
+  )
+  target_include_directories(mptest PUBLIC
+    ${CAPNP_INCLUDE_DIRECTORY}
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/src>
+  )
+  target_link_libraries(mptest PRIVATE CapnProto::capnp)
+  target_link_libraries(mptest PRIVATE CapnProto::capnp-rpc)
+  target_link_libraries(mptest PRIVATE CapnProto::kj)
+  target_link_libraries(mptest PRIVATE CapnProto::kj-async)
+  target_link_libraries(mptest PRIVATE CapnProto::kj-test)
+  target_link_libraries(mptest PRIVATE Threads::Threads)
+  target_link_libraries(mptest PRIVATE multiprocess)
+  set_target_properties(mptest PROPERTIES
+    CXX_STANDARD 17
+    CXX_STANDARD_REQUIRED YES)
+
+  add_dependencies(tests mptest)
+  add_test(NAME mptest COMMAND mptest)
+endif()