Try to fix Windows CI (GitHub Actions -- vcpkg manifest mode)

[stephengtuggy]

Fixes #514 (hopefully)

[stefanseefeld]

thanks @stephengtuggy for the patch ! It's definitely a step in the right direction, but apparently not yet complete (the build fails).

[stephengtuggy]

thanks @stephengtuggy for the patch ! It's definitely a step in the right direction, but apparently not yet complete (the build fails).

@stefanseefeld you're welcome. I think I see what the problem is. I neglected to update the include directory passed to the faber commands. That should be fixed now.

[stephengtuggy]

Nope, still not right. And unfortunately, this may not be trivial to fix. I'm not sure if there is a singular Boost include directory that can be passed to faber. I think it may be more like a different include directory for each Boost component. How to handle this situation?

[stephengtuggy]

To eliminate a variable, I am going back to the same vcpkg baseline in the manifest file as was used for vcpkgGitCommitId prior to this PR. Let's see if that helps.

[stefanseefeld]

Perhaps if you use -User . to start looking in the local directory instead of $github.workspace/vcpkg ?
Alternatively, I see that the install root can be set via the vcpkgArguments: '--x-manifest-root=${{ github.workspace }}/vcpkg' directive.

[stephengtuggy]

This command simply searches the <github workspace>/vcpkg directory and all subdirectories for a file named config.hpp. It is literally the equivalent of find "${{ github.workspace}}/vcpkg" -iname 'config.hpp' -type f. And it's not finding the file anywhere! I don't understand what is going on here. Why would this file not be present?

I'm not familiar with -User . in conjunction with the Get-ChildItem command. What would that do?

[stephengtuggy]

Yes, the install root can be set using the vcpkgArguments parameter, but I'm not sure it's best practice to do so.

[stephengtuggy]

It occurs to me that in my other projects that use vcpkg, I generally set the VCPKG_ROOT environment variable explicitly. This might be important. Trying it now.

[stephengtuggy]

Well, I can finally see where config.hpp is. It's in directory D:\a\python\python\969f6665-88a2-4c98-938e-ca9259871fec\vcpkg_installed\x64-windows\include\boost. In other words, '${{ github.workspace }}\<GUID>\vcpkg_installed\$VCPKG_DEFAULT_TRIPLET\include' would be the boost include directory setting for faber.

This raises some more questions: why? Where is this setting coming from? And does the GUID stay the same, or does it change every run?

[stefanseefeld]

That's great progress ! But I agree, having to remember and hardcode such paths is cumbersome and fragile, so best to be avoided. So why not replace all that by a manually defined install root (specified vie vcpkgArguments) ?

[stephengtuggy]

That's great progress ! But I agree, having to remember and hardcode such paths is cumbersome and fragile, so best to be avoided. So why not replace all that by a manually defined install root (specified vie vcpkgArguments) ?

Yes, I guess that makes sense, actually. I was trying to set it using environment variables, but that doesn't seem to be working for some reason. Perhaps something closer to where vcpkg runs is overriding the relevant environment variable.

At any rate, the last run worked! So the GUID seems to stay the same with each run.

[stephengtuggy]

I don't think --x-manifest-root is the correct vcpkg argument for this purpose, by the way. I believe --x-manifest-root tells vcpkg where to find the manifest file (vcpkg.json), not where to install the packages it installs.

[stephengtuggy]

Looks like one can tell vcpkg where to install dependencies using the VCPKG_INSTALLED_DIR environment variable. I will try that.