Demo (a.k.a Downstream Test)

This demo is sort of “integration” test since it verifies a combined set of elements, and they are:

  1. The ability of “downstream” installation of this library.

  2. The ability to find & load entry-points.

  3. The ability to invoke loaded entry-points.

The steps of the test are as follows:

  1. Install the example package, which registers an entry-point to a group called “example.group”

  2. Build the library.

  3. Build the loader executable (linked against the library).

  4. Execute the loader.

  5. Expect to see the output of the pythonic entry-point.

Using the poc conda environment, all commands should be executed from the repo’s top directory. The test requires the following commands to be executed are:

  1. Install the example package:

    cd example-package && pip install . && cd -

  2. Build & install the library

    cmake -S . -B build/upstream  -Wdev -Werror=dev -DCMAKE_INSTALL_PREFIX=$CONDA_PREFIX -DCMAKE_FIND_ROOT_PATH=$CONDA_PREFIX -DENABLE_TESTING=OFF
cmake --build build/upstream --target install

  3. Build the demo (loader) executable

    cmake -S test/downstream -B build/downstream  -Wdev -Werror=dev -DCMAKE_FIND_ROOT_PATH=$CONDA_PREFIX
cmake --build build/downstream

  4. Execute the demo (loader) executable

    ./build/downstream/downstream

When the demo executable is running it will dynamically load entry-point group called "example.group". In that group the demo will find 2 entry-points, one called hello and the other called 42. Then the demo will ignore the hello entry-point since it’s name isn’t a valid name (not an unsigned number) and load the other entry-point (which has a valid name).

Note

Both entry-points names are valid fron the viewpoint of python, however in this library there is some “filterring” of entry-points based on thier names. A very crud filterring technique indeed, but it’s still proves the point - the library is able to filter entry-points by name.

Afterwards the demo will invoke the loaded entry-point (which points to a function called hello in the example package) with b"asdf" as the input. The expected output of the demo is the same as the expected output of calling hello(b"asdf") from the python interpreter (with some addional logging messages). Here is how it suppose to look:

[2025-06-17 19:24:59.812] [info] loading plugins for group example.group
[2025-06-17 19:24:59.841] [warning] Ignoring entry-point named "hello" since it's not an unsigned number!
Got 4 bytes!
They are: b'asdf'