Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Kyle Meyer]

Hello,

I noticed that Emacs packages from the user's profile leak into guix
environment calls.

For example, when I run

    $ guix environment --pure --ad-hoc emacs -- emacs -q

load-path contains the Emacs packages from my main profile.

I expected it to use GUIX_ENVIRONMENT instead (something like the patch
below, I think).

Does guix-emacs-autoload-packages ignore GUIX_ENVIRONMENT by design?  I
suppose one downside of honoring GUIX_ENVIRONMENT is that, if the --pure
flag isn't passed and the package arguments aren't Emacs-related, a user
may be surprised that their Emacs packages are no longer available in
newly created Emacs instances.

Thanks.

-- >8 --
diff --git a/gnu/packages/aux-files/emacs/guix-emacs.el b/gnu/packages/aux-files/emacs/guix-emacs.el
index 2bbd639ff..2d0d50e11 100644
--- a/gnu/packages/aux-files/emacs/guix-emacs.el
+++ b/gnu/packages/aux-files/emacs/guix-emacs.el
@@ -87,9 +87,11 @@ (defun guix-emacs-autoload-packages (&rest profiles)
   (interactive (list (if (fboundp 'guix-read-package-profile)
                          (funcall 'guix-read-package-profile)
                        guix-user-profile)))
-  (let ((profiles (or profiles
-                      (list "/run/current-system/profile"
-                            guix-user-profile))))
+  (let* ((env      (getenv "GUIX_ENVIRONMENT"))
+         (profiles (or profiles
+                       (and env (list env))
+                       (list "/run/current-system/profile"
+                             guix-user-profile))))
     (dolist (profile profiles)
       (let ((dirs (guix-emacs-directories profile)))
         (when dirs
-- 
2.13.3

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Alex Kost]

Kyle Meyer (2017-07-22 21:39 -0400) wrote:

> Hello,
>
> I noticed that Emacs packages from the user's profile leak into guix
> environment calls.

As for me, this is a natural behaviour.  If you want to be safe from any
external packages, site settings, etc., run "emacs -Q".

> For example, when I run
>
>     $ guix environment --pure --ad-hoc emacs -- emacs -q
>
> load-path contains the Emacs packages from my main profile.

Right, but "-q" is not enough here.  If you don't want these packages to
be autoloaded, you need to run emacs with "-Q" or "--no-site-file".

> I expected it to use GUIX_ENVIRONMENT instead (something like the patch
> below, I think).

I wouldn't expect "instead", I would expect "along with".

> Does guix-emacs-autoload-packages ignore GUIX_ENVIRONMENT by design?

No, I think it's just that no one thought about this possibility before (I
mean a possibility to use emacs packages from "guix environment").

> I suppose one downside of honoring GUIX_ENVIRONMENT is that, if the --pure
> flag isn't passed and the package arguments aren't Emacs-related, a user
> may be surprised that their Emacs packages are no longer available in
> newly created Emacs instances.

I'm not sure.  I think if you run "emacs -q", you really want "emacs -Q".
Otherwise, if you start emacs normally, you probably don't want to ignore
emacs packages from your guix profile.

However, I agree that GUIX_ENVIRONMENT should be honored, but as I wrote
*not instead* but *along with* the default profiles.  So if you start
emacs like this:

  guix environment --ad-hoc emacs emacs-wget -- emacs

it should contain emacs-wget in its load-path.  WDYT?

-- 
Alex

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Kyle Meyer]

Alex Kost <alezost@gmail.com> writes:

> Kyle Meyer (2017-07-22 21:39 -0400) wrote:
>
>> I noticed that Emacs packages from the user's profile leak into guix
>> environment calls.
>
> As for me, this is a natural behaviour.  If you want to be safe from any
> external packages, site settings, etc., run "emacs -Q".

I want "-q" rather than "-Q" because I want the Emacs instance to
autoload the Emacs packages that I've given as arguments to "guix
environment".

> I'm not sure.  I think if you run "emacs -q", you really want "emacs -Q".
> Otherwise, if you start emacs normally, you probably don't want to ignore
> emacs packages from your guix profile.

Maybe I'm underestimating all the ways people use "guix environment".
When I use it, I'm interested in getting an isolated environment,
usually for testing, and in this case I don't want the Emacs packages
from my profile.

But sure, I can use "emacs -Q" and then evaluate something similar to
what Guix puts in site-start.el, modifying it to only look at
GUIX_ENVIRONMENT.

> However, I agree that GUIX_ENVIRONMENT should be honored, but as I wrote
> *not instead* but *along with* the default profiles.  So if you start
> emacs like this:
>
>   guix environment --ad-hoc emacs emacs-wget -- emacs
>
> it should contain emacs-wget in its load-path.  WDYT?

I certainly agree with that load-path should include emacs-wget.  I'm
just not sure I agree with the "along with".

Anyway, as I said above, it's easy enough to get the behavior I want
with "emacs -Q" and a custom guix-emacs-autoload-packages call.

Thanks for your thoughts.

-- 
Kyle

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Alex Kost]

Kyle Meyer (2017-07-23 18:29 -0400) wrote:

> Alex Kost <alezost@gmail.com> writes:
>
>> Kyle Meyer (2017-07-22 21:39 -0400) wrote:
>>
>>> I noticed that Emacs packages from the user's profile leak into guix
>>> environment calls.
>>
>> As for me, this is a natural behaviour.  If you want to be safe from any
>> external packages, site settings, etc., run "emacs -Q".
>
> I want "-q" rather than "-Q" because I want the Emacs instance to
> autoload the Emacs packages that I've given as arguments to "guix
> environment".

Oh, right, now I see why "-Q" is not what you want.

>> I'm not sure.  I think if you run "emacs -q", you really want "emacs -Q".
>> Otherwise, if you start emacs normally, you probably don't want to ignore
>> emacs packages from your guix profile.
>
> Maybe I'm underestimating all the ways people use "guix environment".
> When I use it, I'm interested in getting an isolated environment,
> usually for testing, and in this case I don't want the Emacs packages
> from my profile.

OK, now I understand your point and I don't object against your patch.
OTOH I'm pretty sure there are people who will be surprised that when
emacs is started under "guix environment", it ignores packages from the
"~/guix-profile".

>> However, I agree that GUIX_ENVIRONMENT should be honored, but as I wrote
>> *not instead* but *along with* the default profiles.  So if you start
>> emacs like this:
>>
>>   guix environment --ad-hoc emacs emacs-wget -- emacs
>>
>> it should contain emacs-wget in its load-path.  WDYT?
>
> I certainly agree with that load-path should include emacs-wget.  I'm
> just not sure I agree with the "along with".

Now I'm also not sure if "along with" or "instead" is better.  I don't
have a preference, so I agree with any choice :-)

-- 
Alex

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Kyle Meyer]

Alex Kost <alezost@gmail.com> writes:

[...]

>> Maybe I'm underestimating all the ways people use "guix environment".
>> When I use it, I'm interested in getting an isolated environment,
>> usually for testing, and in this case I don't want the Emacs packages
>> from my profile.
>
> OK, now I understand your point and I don't object against your patch.
> OTOH I'm pretty sure there are people who will be surprised that when
> emacs is started under "guix environment", it ignores packages from the
> "~/guix-profile".

OK, given that many (all other? :]) users would expect a different
behavior ...

>>> However, I agree that GUIX_ENVIRONMENT should be honored, but as I wrote
>>> *not instead* but *along with* the default profiles.  So if you start
>>> emacs like this:
>>>
>>>   guix environment --ad-hoc emacs emacs-wget -- emacs
>>>
>>> it should contain emacs-wget in its load-path.  WDYT?
>>
>> I certainly agree with that load-path should include emacs-wget.  I'm
>> just not sure I agree with the "along with".
>
> Now I'm also not sure if "along with" or "instead" is better.  I don't
> have a preference, so I agree with any choice :-)

... I'd say "along with" is better.

As I said in my previous post, it's quite easy for me to get the
behavior I want, so I'd prefer to go with your gut feeling about the
expected behavior.

-- 
Kyle

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Marius Bakke]

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Kyle Meyer <kyle@kyleam.com> writes:

> Alex Kost <alezost@gmail.com> writes:
>
> [...]
>
>>> Maybe I'm underestimating all the ways people use "guix environment".
>>> When I use it, I'm interested in getting an isolated environment,
>>> usually for testing, and in this case I don't want the Emacs packages
>>> from my profile.
>>
>> OK, now I understand your point and I don't object against your patch.
>> OTOH I'm pretty sure there are people who will be surprised that when
>> emacs is started under "guix environment", it ignores packages from the
>> "~/guix-profile".
>
> OK, given that many (all other? :]) users would expect a different
> behavior ...

Wait, isn't this what --pure is for? I haven't followed the discussion,
but I would expect `guix environment` to *add* to my current profile,
and use '--pure' if I want a "clean" environment.

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Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Kyle Meyer]

Marius Bakke <mbakke@fastmail.com> writes:

> Wait, isn't this what --pure is for?  I haven't followed the
> discussion, but I would expect `guix environment` to *add* to my
> current profile, and use '--pure' if I want a "clean" environment.

I think the behavior here is unspecified because --pure is about
unsetting shell variables while this is about how the load-path and
autoloads are set up within an environment's Emacs instance.
Conceptually, though, I agree that a --pure flag would match
guix-emacs-autoload-packages considering only the environment's Emacs
packages, whereas no --pure flag would match adding the environment's to
the current profile's.

But in the discussion so far, I've been assuming that currently there's
not a direct way for guix-emacs-autoload-packages to detect if --pure
was given.  If that's not true, I'd be happy with the behavior you
propose.

-- 
Kyle

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Alex Kost]

Kyle Meyer (2017-07-25 21:40 -0400) wrote:

> Marius Bakke <mbakke@fastmail.com> writes:
>
>> Wait, isn't this what --pure is for?  I haven't followed the
>> discussion, but I would expect `guix environment` to *add* to my
>> current profile, and use '--pure' if I want a "clean" environment.
>
> I think the behavior here is unspecified because --pure is about
> unsetting shell variables while this is about how the load-path and
> autoloads are set up within an environment's Emacs instance.
> Conceptually, though, I agree that a --pure flag would match
> guix-emacs-autoload-packages considering only the environment's Emacs
> packages, whereas no --pure flag would match adding the environment's to
> the current profile's.
>
> But in the discussion so far, I've been assuming that currently there's
> not a direct way for guix-emacs-autoload-packages to detect if --pure
> was given.  If that's not true, I'd be happy with the behavior you
> propose.

I also don't see how you can detect from Emacs if it is running from
guix environment with --pure or without.

-- 
Alex

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Ricardo Wurmus]

Alex Kost <alezost@gmail.com> writes:

> Kyle Meyer (2017-07-25 21:40 -0400) wrote:
>
>> Marius Bakke <mbakke@fastmail.com> writes:
>>
>>> Wait, isn't this what --pure is for?  I haven't followed the
>>> discussion, but I would expect `guix environment` to *add* to my
>>> current profile, and use '--pure' if I want a "clean" environment.
>>
>> I think the behavior here is unspecified because --pure is about
>> unsetting shell variables while this is about how the load-path and
>> autoloads are set up within an environment's Emacs instance.
>> Conceptually, though, I agree that a --pure flag would match
>> guix-emacs-autoload-packages considering only the environment's Emacs
>> packages, whereas no --pure flag would match adding the environment's to
>> the current profile's.
>>
>> But in the discussion so far, I've been assuming that currently there's
>> not a direct way for guix-emacs-autoload-packages to detect if --pure
>> was given.  If that's not true, I'd be happy with the behavior you
>> propose.
>
> I also don't see how you can detect from Emacs if it is running from
> guix environment with --pure or without.

I don’t think you can, but we could pollute the environment some more by
setting a variable that indicates that this is a pure environment…?

-- 
Ricardo

GPG: BCA6 89B6 3655 3801 C3C6  2150 197A 5888 235F ACAC
https://elephly.net

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Alex Kost]

Kyle Meyer (2017-07-24 18:25 -0400) wrote:

> Alex Kost <alezost@gmail.com> writes:
>
> [...]
>
>>>> However, I agree that GUIX_ENVIRONMENT should be honored, but as I wrote
>>>> *not instead* but *along with* the default profiles.  So if you start
>>>> emacs like this:
>>>>
>>>>   guix environment --ad-hoc emacs emacs-wget -- emacs
>>>>
>>>> it should contain emacs-wget in its load-path.  WDYT?
>>>
>>> I certainly agree with that load-path should include emacs-wget.  I'm
>>> just not sure I agree with the "along with".
>>
>> Now I'm also not sure if "along with" or "instead" is better.  I don't
>> have a preference, so I agree with any choice :-)
>
> ... I'd say "along with" is better.
>
> As I said in my previous post, it's quite easy for me to get the
> behavior I want, so I'd prefer to go with your gut feeling about the
> expected behavior.

OK, so if the others agree with "along with" policy, would you like to
update your patch for it?

-- 
Alex

Re: Should guix-emacs-autoload-packages use GUIX_ENVIRONMENT?

[Kyle Meyer]

Alex Kost <alezost@gmail.com> writes:

> OK, so if the others agree with "along with" policy, would you like to
> update your patch for it?

Sure, sent to guix-patches (#27845).

-- 
Kyle