C++ Build System and Testing Framework for Google Code Jam

This is a tiny setup I prepared to make my sporadic participation in Google Code Jam contests a bit more comfortable.

It is only tested on Linux but should in principle run on all platforms with support for Meson, Google Test and of course GCC.

Prerequisites

Since Code Jam 2020, for C++ solutions gcc 8.3.0 is used with the following compilation line:

g++ solution.cpp -std=c++17 -pthread -O2 -o solution

• Meson build system with the Ninja backend
• Google's C++ test framework Google Test

On Debian-based systems use apt to install the following packages:

sudo apt install meson ninja libgtest-dev 

If meson is not provided by your package manager, you can use the python 3 installer:

pip3 install meson

Getting Started

For each round of a Code Jam contest, make a copy of the folder template (e.g. 2025/Round2b) and add an include instruction to the end of meson.build. Add any helper files provided by Google for a particular round.

For each round a pair of source file and corresponding tests is provided (e.g. A.cpp and A-test.cpp). Integrate your solution in the former while adding test to the latter.

The macros provided in include/testing.h allow you to perform unit testing on the solution's main() function, providing input and capturing the output as a whole, without having to account for it in the solution file at all. It means that after successful debugging and unit testing of your solution, you can simply copy&paste the complete contents of the file to the competition dashboard.

Compiling and Testing

• Setup meson in an out-of-source build directory (e.g. a subdirectory in the project root):

mkdir build
cd build
meson .. [--prefix=/install/dir] [--buildtype=(plain|debug|debugoptimized|release)]

• Use mesonconf to revise or modify your configuration:

mesonconf .

• Both meson(.py) and mesonconf(.py) offer decent command-line help if executed with the option --help.
• To compile the code, execute ninja in the build directory:

ninja [-v]

• Execute all unit tests using the following command:

ninja test

Of course you can execute the compiled solution executables or test individually from the build directory (there is no need to perform 'ninja install').