provide meaningful error message when failing sanity step

[xaver42]

Trying to build this recipy:
https://gist.github.com/xaver42/5822924
the build fails with "Sanity check for YAMLSyck failed!"

Checking the logfile it takes some time to find the real error (disguised as a warning):
main.PerlModule WARNING Extension: YAMLSyck failed to install! (output: No module found for "YAML::Syck".
)

But even with this message I am puzzled, because the module is already installed at that time in easybuild's "software" directory.

So it would be good if:

1. An error leading to the failure of the step is clearly marked as such in the log
2. The framework reports where it looked for the files that were not found.

[boegel]

This is probably caused by the Perl module name you should specify when you want to use it, i.e. use YAML::Syck is probably not what you expect it to be.
So, it's not really a case of EB not finding a particular file, but rather Perl not being able to use the module with the name you've specified.
My guess would be that you need to adjust the following line in your easyconfig file to specify the correct Perl module name:

options = {'modulename': 'YAML::Syck'}

@xaver42 : That being said: you're right, the error message could be a lot clearer here. We'll look into that, issue a PR and ask you to take a look at it. But it's going to be post-v1.6 though.

[xaver42]

use YAML::Syck is the way to use that module, so this is not the problem (or did I misunderstand your comment?).

@boegel with PR you mean a PR for this module? Even if it dosn't build properly?

[boegel]

@xaver42: OK, then something else is going on, e.g. an incomplete Perl search path. We fixed something related to that in EB v1.6 (see easybuilders/easybuild-easyblocks#209).

With PR I mean a pull request for easybuild-framework that makes the error message clearer (and which isn't there yet right now).

[xaver42]

Sorry, I don't know enough about the internals of easybuild-framework to create a PR.

Edit: Ah, I think now I understand: You issue a PR, and I check whether this creates a more readable error message!?

[boegel]

@xaver42: Don't worry, we can look into that. I was not trying to convince you to issue a PR te resolve this (I know the framework can be quite daunting), I was just informing you that we're aware of the issue, and will look into it. We already made sanity check errors a lot more clear for non-extensions, we should do it for extensions as well.

[boegel]

@xaver42: Should be fixed by #672.