mfc-candidates: filter out candidates marked to not be MFCed

[bz]

Summary

Some people use {X,}-MFC: {NO,no,never} to mark commits to not be
MFCed. Searching your ocmmits manually and putting them in an
exclude file is tedious so automate this.

[bz]

Probably not the most elegant solution and adds awk as a dependency but seems to work.

Other ones I was pondering which is used more often is "X-MFC with" to sort them together (a bit more tricky to implement) and X-MFC to: (to sort out commits_to which are not intended to be MFCed to the target branch). Probably should be options...?

Basically I didn't want to lose this and put it out for further consideration.

[imp]

Any reason we do also add an exclude file? You never really know at commit time for some changes. Later you discover the problems...

Apart from this adding yet another pass over all the commits since the branch point, it isn't bad.

I have a similar script I should see if it's better or not...

[emaste]

We support an exclude file already, with -X exclude_file.

I don't object to this functionality but am worried about increased runtime. We could perhaps check only the candidates found, i.e. in the while read hash; do loop just below?

[bz]

In D42074#960210, @emaste wrote:

We support an exclude file already, with -X exclude_file.

I don't object to this functionality but am worried about increased runtime. We could perhaps check only the candidates found, i.e. in the while read hash; do loop just below?

Sounds like a way more intelligent solution :) I'll update this the next days.

[imp]

Love -X... somehow missed it.

Maybe we should add per stable branch versions of it? My FreeBSD changes are a big false positive hit for example

[emaste]

Hmm, forgot about this. We'll probably want to reimplement it on top of D47416.

[bz]

I think I should have abandoned it. Not that I love Lua but -X has since done my job, especially since -X can have comments.