Add superproject CMake tests to Travis and Appveyor

.travis.yml

@@ -315,6 +315,14 @@ matrix:
       - cmake --build .
       - cmake --build . --target check
 
+    - os: linux
+      compiler: clang++
+      env: BOOST_CMAKE=1
+      script:
+        - mkdir __build__ && cd __build__
+        - cmake -DBOOST_ENABLE_CMAKE=1 -DBoost_VERBOSE=1 ..
+        - ctest --output-on-failure -R boost_mp11
+
 install:
   - BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
   - cd ..

appveyor.yml

@@ -22,6 +22,12 @@ environment:
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
       TOOLSET: msvc-14.2
       CXXSTD: 14,17
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+      CMAKE: 1
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      CMAKE: 1
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      CMAKE: 1
 
 install:
   - set BOOST_BRANCH=develop
@@ -39,4 +45,8 @@ build: off
 
 test_script:
   - if not "%CXXSTD%" == "" set CXXSTD=cxxstd=%CXXSTD%
-  - b2 -j3 libs/mp11/test toolset=%TOOLSET% %CXXSTD% address-model=32,64 variant=debug,release
+  - if "%CMAKE%" == ""  b2 -j3 libs/mp11/test toolset=%TOOLSET% %CXXSTD% address-model=32,64 variant=debug,release
+
+  - if not "%CMAKE%" == ""  mkdir __build__ && cd __build__
+  - if not "%CMAKE%" == ""  cmake -DBOOST_ENABLE_CMAKE=1 -DBoost_VERBOSE=1 ..
+  - if not "%CMAKE%" == ""  for %%c in (Debug Release MinSizeRel RelWithDebInfo) do cmake --build . --config %%c && ctest --output-on-failure -R boost_mp11 -C %%c