fprime-util generate does not forward CMake exit code

[vietjtnguyen]

F´ Version	3.0.0
Affected Component	fprime-tools

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Problem Description

fprime-util generate does not forward the exit code from the CMake configuration step. This means a failed CMake configuration step does not mean fprime-util generate fails (according to exit code). This was caught because my CI proceeded despite CMake configuration errors.

How to Reproduce

git clone --recursive -b dev-non-forwarded-exit-code git@github.jpl.nasa.gov:vnguyen/tmp-fprime-build.git
cd tmp-fprime-build
python3 -m venv venv
source venv/bin/activate
pip install fprime-tools
cd fprime-cadre
fprime-util generate
echo $? # note that it is zero despite CMake failure

Expected Behavior

The exit codes for subprocesses that fail (such as the CMake configuration invocation) should be returned by the fprime-util generate tool.