Add missing has_documentation to MxCommand

[JornVernee]

Running mx help <command> throws 'MxCommand' object has no attribute 'has_documentation'. This PR adds that missing function.

This PR:

• Replaces has_documentation with get_doc, since this simplifies usage.
• Makes sure the unittest command passes a doc function instead of a doc string (and removed extra newlin in doc string)
• Makes sure the get_doc function actually returns the documentation string.

[JornVernee]

Actually, looking at some of the use cases, like unittest https://github.com/graalvm/mx/blob/master/mx_unittest.py#L351 the documentation never makes it into the doc message because the function right now expects the command's doc string to be a format string.

I think I have a way to fix this.

[graalvmbot]

Hello JornVernee, thanks for contributing a PR to our project!

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[dougxc]

Hi @JornVernee , can you please ensure all your commits are made with your real email address. This will avoid the complaints by the graalvmbot.

[JornVernee]

@dougxc Ah ok. I purposely stopped adding my emails to the commits since I was getting a lot of recruitment spam.

I will add the email with the next commit.

[dougxc]

Thanks and sorry to hear about the spam.

You'll also need to redo the commit (rebase) that is using the github email address.

[JornVernee]

Not sure why Travis is choking, I can not reproduce that error on my machine. Is something going on with the CI setup?

[gilles-duboscq]

Not sure why Travis is choking, I can not reproduce that error on my machine. Is something going on with the CI setup?

Seems to be an issue with the JDT (eclipse compiler/ECJ) JAR which comes from there:

mx/.travis.yml

Line 18 in 9c00c2e

wget http://www.eclipse.org/downloads/download.php?file=/eclipse/downloads/drops4/R-4.5.2-201602121500/ecj-4.5.2.jar -O $JDT

At least locally this URL works fine. I'm not sure what's going on. Maybe the download got corrupted?

[JornVernee]

@gilles-duboscq I went to the URL and there seems to be no re-direct to https:// either (I had that problem a few days ago on another project)

But using https:// also seems to work, maybe you could try switching to that?

[JornVernee]

@gilles-duboscq Well, I implemented your changes and the travis check is passing as well now. My other PR had the same problem: #172 Is there any way you could re-run the check?

Thanks

[gilles-duboscq]

Looks good now, thank you!

Regarding #172, maybe once this is integrated, you can rebase it? For some reason it seems to also contain the changes from #164 which has already been integrated so maybe a rebase is anyway a good idea.

[gilles-duboscq]

Also this is changing a line with print so it will definitely conflict with #172.

[JornVernee]

OK, I'll do that after this is integrated then. Then I can make sure there's no other conflicts or weird diffs with mx/master at that point as well.