Added a CMakeFiles.txt to be able to use current from another project as a cmake project.

[dkorolev]

Case in point: https://github.com/dkorolev/cmake_trivial_2023/blob/main/CMakeLists.txt#L32

To try:

(git clone -b cmake_friendly git@github.com:c5t/current current_cmake_friendly && cd current_cmake_friendly && make cmake_test)

Note: This will use up all the CPUs on the machine! The tests will build quickly though.

Also, the tests pass when run from a directory the full path name of which contains spaces. This is not the case as of now with our "standard" way to run the tests. Looks like cmake is doing some things right indeed!

[mzhurovich]

Fails on MacOS:

In file included from /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.3.sdk/System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:8:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX13.3.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSObjCRuntime.h:601:1: error: expected unqualified-id
@class NSString, Protocol;
...
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
make[3]: *** [CMakeFiles/midichlorians_server_test.dir/midichlorians/server/test.cc.o] Error 1
make[2]: *** [CMakeFiles/midichlorians_server_test.dir/all] Error 2
make[2]: *** Waiting for unfinished jobs....
20 errors generated.
make[3]: *** [CMakeFiles/midichlorians_client_test.dir/midichlorians/client/test.cc.o] Error 1
make[2]: *** [CMakeFiles/midichlorians_client_test.dir/all] Error 2
20 errors generated.
make[3]: *** [CMakeFiles/midichlorians_test.dir/midichlorians/test.cc.o] Error 1
make[2]: *** [CMakeFiles/midichlorians_test.dir/all] Error 2

I suspect there's something wrong with either the flags (-x objective-c++ should be present), or how it builds stuff in general but I didn't dig deeper.

[dkorolev]

@mzhurovich let's close this one for now, in favor of #944.

The latter makes smaller steps, tested through including on macOS. It's also more CCH-friendly!