This is the repl overlay from my dotfiles, which I think provides a
reasonable and ergonomic set of variables. We can iterate on this over
time, or (perhaps?) provide a sentinel value like `repl-overlays =
<DEFAULT>` to include a "suggested default" overlay like this one.
Change-Id: I8eba3934c50fbac8367111103e66c7375b8d134e
There have been multiple setting types for paths that are supposed to be
canonicalised, depending on whether zero or one, one, or any number of paths is
to be specified. Naturally, they behaved in slightly different ways in the
code. Simplify things by unifying them and removing special behaviour (mainly
the "multiple paths type can coerce to boolean" thing).
Change-Id: I7c1ce95e9c8e1829a866fb37d679e167811e9705
We got UBSan working on Lix, so we of course immediately found a bug and
some definitely nonsense behaviour.
Accessing `pureEval` or `restrictEval` from a default setting value is
nonsense, since they would never be actually set by the time that value
is set so they are not going to do anything. The configuration is not
applied in an initializer (and even if it were, it's not going to be in
the right order).
After looking into *that*, we hunted down what actually was applying
these, since clearly this code did not do anything. The EvalState
constructor should have a "search path added and removed here :)" sign
on it, because that's where it is done. We added an explicit
initialization of the optional in there because it was otherwise unclear
why pureEval also has the search path to allowed paths setup code run.
We then realized that the `pureEval` documentation was *also* bogus, and
we rewrote it. In so doing, we realized that we forgot to file a bug to
make `builtins.storePath` work in pure eval mode, so we filed one of
those: https://git.lix.systems/lix-project/lix/issues/402
Yaks have been thoroughly shorn.
UBSan report:
../src/libexpr/eval-settings.cc:66:10: runtime error: member call on address 0x752fa9a13060 which does not point to an object of type 'nix::BaseSetting<b
ool>'
0x752fa9a13060: note: object has invalid vptr
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
^~~~~~~~~~~~~~~~~~~~~~~
invalid vptr
0 0x752fa95106a6 in nix::EvalSettings::getDefaultNixPath[abi:cxx11]() /home/jade/lix/lix2/build/src/libexpr/eval-settings.cc:66:10
1 0x752fa950e420 in nix::EvalSettings::EvalSettings() /home/jade/lix/lix2/build/src/libexpr/eval-settings.hh:36:15
2 0x752fa9469f1f in __cxx_global_var_init.50 /home/jade/lix/lix2/build/src/libexpr/eval-settings.cc:98:14
3 0x752fa9469f1f in _GLOBAL__sub_I_eval_settings.cc /home/jade/lix/lix2/build/src/libexpr/eval-settings.cc
4 0x752fabbd308d in call_init (/nix/store/k7zgvzp2r31zkg9xqgjim7mbknryv6bs-glibc-2.39-52/lib/ld-linux-x86-64.so.2+0x508d) (BuildId: a5b8228edc9f16078ac3c894af964eeb990ecb4c)
5 0x752fabbd317b in _dl_init (/nix/store/k7zgvzp2r31zkg9xqgjim7mbknryv6bs-glibc-2.39-52/lib/ld-linux-x86-64.so.2+0x517b) (BuildId: a5b8228edc9f16078ac3c894af964eeb990ecb4c)
6 0x752fabbe9c2f in _dl_start_user (/nix/store/k7zgvzp2r31zkg9xqgjim7mbknryv6bs-glibc-2.39-52/lib/ld-linux-x86-64.so.2+0x1bc2f) (BuildId: a5b8228edc9f16078ac3c894af964eeb990ecb4c)
Change-Id: I5d8ffb7bfbe24b6584020ac74eed93d9f2e6d111
Both of these still needs their own actual documentation, but they are
at least now mentioned that they exist and what they're enabled by.
Change-Id: I235b9e8e627e04ed06611423c8e67a8eca233120
Adds a `repl-overlays` option, which specifies files that can overlay
and modify the top-level bindings in `nix repl`. For example, with the
following contents in `~/.config/nix/repl.nix`:
info: final: prev: let
optionalAttrs = predicate: attrs:
if predicate
then attrs
else {};
in
optionalAttrs (prev ? legacyPackages && prev.legacyPackages ? ${info.currentSystem})
{
pkgs = prev.legacyPackages.${info.currentSystem};
}
We can run `nix repl` and use `pkgs` to refer to `legacyPackages.${currentSystem}`:
$ nix repl --repl-overlays ~/.config/nix/repl.nix nixpkgs
Lix 2.90.0
Type :? for help.
Loading installable 'flake:nixpkgs#'...
Added 5 variables.
Loading 'repl-overlays'...
Added 6 variables.
nix-repl> pkgs.bash
«derivation /nix/store/g08b5vkwwh0j8ic9rkmd8mpj878rk62z-bash-5.2p26.drv»
Change-Id: Ic12e0f2f210b2f46e920c33088dfe1083f42391a
Enter debugger on `builtins.trace` with an option
(cherry picked from commit 774e7ca5847ebc392eac2a124a8f12b24da4f65a)
Change-Id: If01e2110b3a128e639b05143227e365227d149f1
Fix segfault on infinite recursion in some cases
(cherry picked from commit bf1b294bd81ca76c5ec9fe3ecd52196bf52a8300)
Change-Id: Id137541426ec8536567835953fccf986a3aebf16
Avoid duplicated code, and also avoid "on the fly" path construction
(which makes it harder to keep track of which paths we use).
The factored out code doesn't create the Nix state dir anymore, but this
is fine because other in nix-env and nix-channel does:
- nix-channel: Line 158 in this commit
- nix-env: Line 1407 in this commit