The README suggests using PackageManager wrongly

[wilfwilson]

The README suggests doing

gap -c 'LoadPackage("PackageManager"); InstallPackage("https://github.com/gap-packages/orb"); QUIT;'

to clone orb, but that doesn't work:

gap> InstallPackage("https://github.com/gap-packages/orb");
#I  Getting PackageInfo URLs...
#I  Package "https://github.com/gap-packages/orb" not found in package list
false

Instead it wants you to use https://github.com/gap-packages/orb.git. I think it would be nice if PackageManager did do this, though. I made an issue requesting it at gap-packages/PackageManager#148.

[wilfwilson]

Also, and I think this is possibly important, I'm not 100% sure that, within GitHub Actions, PackageManager will actually install packages in a location that GAP will find when it comes to loading packages. This is something to check.

[wilfwilson]

Also, it seems that PackageManager will refuse to build a package via InstallPackage if compiling the documentation does not produce a PDF file. This is problematic if we don't have LaTeX installed, right? Also something to check.

[stertooy]

Instead it wants you to use https://github.com/gap-packages/orb.git.

Oops. I'll edit it.

Also, and I think this is possibly important, I'm not 100% sure that, within GitHub Actions, PackageManager will actually install packages in a location that GAP will find when it comes to loading packages. This is something to check.

This works :)

Also, it seems that PackageManager will refuse to build a package via InstallPackage if compiling the documentation does not produce a PDF file. This is problematic if we don't have LaTeX installed, right? Also something to check.

I can't seem to reproduce this.

#I  Created directory /home/runner/.gap/pkg/
#I  Cloning to /home/runner/.gap/pkg/polycyclic ...
#I  Package cloned successfully
#I  Checking dependencies for Polycyclic...
#I    alnuth 3.0: true
#I    autpgrp 1.6: true
#I  Building documentation (using makedoc.g)...
#I  PackageInfo.g validation failed
#I  (in /home/runner/.gap/pkg/polycyclic)
#I  There may be problems with the package

So I get a bunch of warnings, but the return value is still true and the installed package does load.

[wilfwilson]

Thanks for checking that!

[stertooy]

As a follow-up on this:

Also, it seems that PackageManager will refuse to build a package via InstallPackage if compiling the documentation does not produce a PDF file. This is problematic if we don't have LaTeX installed, right? Also something to check.

Turns out this is somewhat of a problem for older versions of PackageManager. The package still gets built and is usable, but PackageManager will throw an error. So we're forced to either ignore the error or install LaTeX.

Anyway, I think this is probably something that should be looked at in the install-pkg action. Once that's released, we can update the README here.