fprime-util impl "has no associated build cache path" message clarity

[celskeggs]

F´ Version	v3.5.1
Affected Component	fprime-util

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Problem Description

If a developer forgets to add add_fprime_subdirectory for a new component, and then runs fprime-util impl or fprime-util impl --ut, they get a confusing error message:

# fprime-util impl --ut
Built target refresh_cache
[ERROR] /absolute/path/to/Project/Components/Namespace/ComponentName has no associated build cache path

(Where /absolute/path/to/Project/Components/Namespace/ComponentName is the absolute path to the component directory.)

While this error message makes sense from an internal perspective, it doesn't help a user who isn't familiar with the internals of the build system. I suggest that fprime-util should produce a message like this:

# fprime-util impl --ut
Built target refresh_cache
[ERROR] The call to add_fprime_subdirectory could not be found for ComponentName
Please check the CMakeLists.txt files in the parent directories of /absolute/path/to/Project/Components/Namespace/ComponentName

This message reframes the error from the user's perspective instead of the implementation's perspective.

Context / Environment

Execute fprime-util version-check and share the output.

Operating System: Linux
CPU Architecture: x86_64
Platform: Linux-5.15.167.4-microsoft-standard-WSL2-x86_64-with-glibc2.34
Python version: 3.9.21
CMake version: 3.26.5
Pip version: 21.3.1
Pip packages:
    fprime-tools==3.5.1
    fprime-gds==3.5.2a1
    fprime-fpp-*==2.2.1
Project submodules:
    https://github.com/nasa/fprime.git @ v3.5.1-3-g231cfdb11
    https://github.com/fprime-community/fprime-baremetal.git @ 6fa7db9

How to Reproduce

1. Create a new component but do not generate unit tests
2. Leave out or remove the add_fprime_subdirectory("${CMAKE_CURRENT_LIST_DIR}/ComponentName/") call in the appropriate CMakeLists.txt
3. Run fprime-util impl --ut

Expected Behavior

See above.

[LeStarch]

Suggested steps to fix:

1. Search for the error string "has no associated build cache path" in fprime/cmake and fprime-tools
2. Update error message

[Lando-Lopez]

Hackers,
I found the error message inside fprime-tools/src/fprime/fbuild/builder.py
and opened a PR to improve it: [nasa/fprime-tools#251]

Should make the DX a bit nicer for devs hitting this issue.