pixi shell not re-activating after an add is executed

[HaoZeke]

Checks

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pixi, using pixi --version.

Reproducible example

pixi init
pixi shell
pixi add eigen pkg-config
pkg-config --cflags eigen3
Package eigen3 was not found in the pkg-config search path.
Perhaps you should add the directory containing `eigen3.pc'
to the PKG_CONFIG_PATH environment variable
No package 'eigen3' found

This should work. Since it doesn't meson also doesn't pick up pixi installed eigen.

Issue description

To get it to work one must manually set PKG_CONFIG_PATH:

pixi shell
export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:$CONDA_PREFIX/share/pkgconfig
pkg-config --cflags eigen3
-I/home/<redacted>/.pixi/env/include/eigen3

Expected behavior

PKG_CONFIG_PATH should be set by pixi when pkg-config is part of the environment. That is:

pixi init
pixi shell
pixi add pkg-config eigen
pkg-config --cflags eigen3
-I/home/<redacted>/.pixi/env/include/eigen3

[baszalmstra]

Does this only happen when using pixi? Or does this also happen when you use (micro)mamba/conda?

If this also happens for those programs than most likely the eigen package does not include this information. You would have to check the eigen feedstock.

[HaoZeke]

Does this only happen when using pixi? Or does this also happen when you use (micro)mamba/conda?

If this also happens for those programs than most likely the eigen package does not include this information. You would have to check the eigen feedstock.

No it is just a pixi thing, micromamba works.

micromamba create -p $(pwd)/.tmp
micromamba activate -p $(pwd)/.tmp
micromamba install pkg-config eigen
pkg-config --cflags eigen3
-I/<redacted>/.tmp/include/eigen3

[wolfv]

I think what happens is that the pixi shell is not re-activated after an installation happened. Maybe we should (in a pixi shell) install a hook so that a reactivation is triggered (we do that actually in micromamba).