Re: [Quilt-dev] How is one supposed to use guards(1) alongside quilt(1)?

[Oleksandr Gavenko]

On 2021-02-12, Xavier Morel via Quilt-dev wrote:

> Does quilt(1) have some sort of integration so guards(1) is automatically 
> applied before quilt(1)
> looks at the series file, or does guards(1) have to be explicitely applied to 
> a
> series-file-with-guards in order to generate series files, with new patches 
> then having to be 
> copied manually to the "reference" file with guards? Or some other way I did 
> not think of?

I checked sources: quilt command delegates work to scripts under internally
defined QUILT_DIR and prints every available script names if you run quilt
without arguments:

  Commands are:
        add       fold    new       remove    top
        annotate  fork    next      rename    unapplied
        applied   graph   patches   revert    upgrade
        delete    grep    pop       series
        diff      header  previous  setup
        edit      import  push      snapshot
        files     mail    refresh   switch

There is no guards. Also there are no occurrences in Git sources:

  git clone https://git.savannah.nongnu.org/git/quilt.git
  cd quilt
  grep -R guards quilt/

So you have to use guards(1) as standalone app, there is no integration.

> The guards(1) utility is packaged as part of the quilt distribution, but it's 
> a bit unclear how it's
> supposed to be used, possibly more so because I have experience with 
> Mercurial's `mq` where guards
> are supported natively. I have looked at the man pages, but didn't find 
> explanations of using the two together, and while the README

I haven't heard about "hg qguard" until now. I actively used hg mq but
nowadays Git is widespread and I started to use quilt instead of MQ.

As for guard there is an open question:

  
https://stackoverflow.com/questions/65934503/how-do-you-use-guards1-with-quilt1

and the utility has been bundled since 2003...

To familiarize with the concept I tried the guards:

  # mkdir patches
  # touch patches/first.patch
  # touch patches/second.patch


  # printf -- "first.patch\n" | guards --check --prefix=patches
  Unused: second.patch

  # printf -- "first.patch\n" | guards --prefix=patches
  patches/first.patch


  # printf -- "+ok first.patch\n" | guards --check --prefix=patches ok
  Unused: second.patch

  # printf -- "+ok first.patch\n" | guards --prefix=patches ok
  patches/first.patch

  # printf -- "+ok first.patch\n" | guards --prefix=patches fail


  # printf -- "+ok first.patch\n-fail second.patch\n" | guards --check 
--prefix=patches ok fail

  # printf -- "+ok first.patch\n-fail second.patch\n" | guards --prefix=patches 
ok fail
  patches/first.patch


  # printf -- "+ok first.patch\n-fail second.patch\nthird.patch\n" | guards 
--check --prefix=patches ok fail
  Not found: patches/third.patch

  # printf -- "+ok first.patch\n-fail second.patch\nthird.patch\n" | guards 
--prefix=patches ok fail
  patches/first.patch
  patches/third.patch


So guards(1) is preprocessor for config file following syntax:

  +xxx Include the file(s) on this line if the symbol xxx is defined.
  -xxx Exclude the file(s) on this line if the symbol xxx is defined.
  +!xxx Include the file(s) on this line if the symbol xxx is not defined.
  -!xxx Exclude the file(s) on this line if the symbol xxx is not defined.

with option to find orphan or missing files to generate series file.

I think there should be integration of quilt and guards. Like storing
currently selected guards in .pc directory and overall replicate HG MQ CLI.

-- 
http://defun.work/