forked from lix-project/lix
Maximilian Bosch
98946e2d9c
Basically an attempt to resume fixing #5543 for a breakage introduced
earlier[1]. Basically, when evaluating an older `nixpkgs` with
`nix-shell` the following error occurs:
λ ma27 [~] → nix-shell -I nixpkgs=channel:nixos-18.03 -p nix
error: anonymous function at /nix/store/zakqwc529rb6xcj8pwixjsxscvlx9fbi-source/pkgs/top-level/default.nix:20:1 called with unexpected argument 'inNixShell'
at /nix/store/zakqwc529rb6xcj8pwixjsxscvlx9fbi-source/pkgs/top-level/impure.nix:82:1:
81|
82| import ./. (builtins.removeAttrs args [ "system" "platform" ] // {
| ^
83| inherit config overlays crossSystem;
This is a problem because one of the main selling points of Nix is that
you can evaluate any old Nix expression and still get the same result
(which also means that it *still evaluates*). In fact we're deprecating,
but not removing a lot of stuff for that reason such as unquoted URLs[2]
or `builtins.toPath`. However this property was essentially thrown away
here.
The change is rather simple: check if `inNixShell` is specified in the
formals of an auto-called function. This means that
{ inNixShell ? false }:
builtins.trace inNixShell
(with import <nixpkgs> { }; makeShell { name = "foo"; })
will show `trace: true` while
args@{ ... }:
builtins.trace args.inNixShell
(with import <nixpkgs> { }; makeShell { name = "foo"; })
will throw the following error:
error: attribute 'inNixShell' missing
This is explicitly needed because the function in
`pkgs/top-level/impure.nix` of e.g. NixOS 18.03 has an ellipsis[3], but
passes the attribute-set on to another lambda with formals that doesn't
have an ellipsis anymore (hence the error from above). This was perhaps
a mistake, but we can't fix it anymore. This also means that there's
AFAICS no proper way to check if the attr-set that's passed to the Nix
code via `EvalState::autoCallFunction` is eventually passed to a lambda
with formals where `inNixShell` is missing.
However, this fix comes with a certain price. Essentially every
`shell.nix` that assumes `inNixShell` to be passed to the formals even
without explicitly specifying it would break with this[4]. However I think
that this is ugly, but preferable:
* Nix 2.3 was declared stable by NixOS up until recently (well, it still
is as long as 21.11 is alive), so most people might not have even
noticed that feature.
* We're talking about a way shorter time-span with this change being
in the wild, so the fallout should be smaller IMHO.
[1]
|
||
|---|---|---|
| .. | ||
| ca | ||
| config | ||
| lang | ||
| plugins | ||
| add.sh | ||
| bad.tar.xz | ||
| bash-profile.sh | ||
| big-derivation-attr.nix | ||
| binary-cache-build-remote.sh | ||
| binary-cache.sh | ||
| brotli.sh | ||
| build-dry.sh | ||
| build-hook-ca-fixed.nix | ||
| build-hook-ca-floating.nix | ||
| build-hook.nix | ||
| build-remote-content-addressed-fixed.sh | ||
| build-remote-content-addressed-floating.sh | ||
| build-remote-input-addressed.sh | ||
| build-remote.sh | ||
| build.sh | ||
| ca-shell.nix | ||
| case-hack.sh | ||
| case.nar | ||
| check-refs.nix | ||
| check-refs.sh | ||
| check-reqs.nix | ||
| check-reqs.sh | ||
| check.nix | ||
| check.sh | ||
| common.sh.in | ||
| compression-levels.sh | ||
| compute-levels.sh | ||
| config.nix.in | ||
| config.sh | ||
| db-migration.sh | ||
| dependencies.builder0.sh | ||
| dependencies.nix | ||
| dependencies.sh | ||
| describe-stores.sh | ||
| dummy | ||
| dump-db.sh | ||
| eval-store.sh | ||
| eval.nix | ||
| eval.sh | ||
| export-graph.nix | ||
| export-graph.sh | ||
| export.sh | ||
| failing.nix | ||
| fetchClosure.sh | ||
| fetchGit.sh | ||
| fetchGitRefs.sh | ||
| fetchGitSubmodules.sh | ||
| fetchMercurial.sh | ||
| fetchPath.sh | ||
| fetchTree-file.sh | ||
| fetchurl.sh | ||
| filter-source.nix | ||
| filter-source.sh | ||
| fixed.builder1.sh | ||
| fixed.builder2.sh | ||
| fixed.nix | ||
| fixed.sh | ||
| flake-bundler.sh | ||
| flake-local-settings.sh | ||
| flake-searching.sh | ||
| flakes-run.sh | ||
| flakes.sh | ||
| fmt.sh | ||
| fmt.simple.sh | ||
| function-trace.sh | ||
| gc-auto.sh | ||
| gc-concurrent.builder.sh | ||
| gc-concurrent.nix | ||
| gc-concurrent.sh | ||
| gc-concurrent2.builder.sh | ||
| gc-non-blocking.sh | ||
| gc-runtime.nix | ||
| gc-runtime.sh | ||
| gc.sh | ||
| github-flakes.nix | ||
| hash-check.nix | ||
| hash.sh | ||
| import-derivation.nix | ||
| import-derivation.sh | ||
| impure-derivations.nix | ||
| impure-derivations.sh | ||
| init.sh | ||
| install-darwin.sh | ||
| lang.sh | ||
| linux-sandbox.sh | ||
| local-store.sh | ||
| local.mk | ||
| logging.sh | ||
| misc.sh | ||
| multiple-outputs.nix | ||
| multiple-outputs.sh | ||
| nar-access.nix | ||
| nar-access.sh | ||
| nix-build-examples.nix | ||
| nix-build.sh | ||
| nix-channel.sh | ||
| nix-copy-closure.nix | ||
| nix-copy-ssh.sh | ||
| nix-profile.sh | ||
| nix-shell.sh | ||
| nix_path.sh | ||
| nss-preload.nix | ||
| optimise-store.sh | ||
| parallel.builder.sh | ||
| parallel.nix | ||
| parallel.sh | ||
| pass-as-file.sh | ||
| path.nix | ||
| placeholders.sh | ||
| plugins.sh | ||
| post-hook.sh | ||
| pure-eval.nix | ||
| pure-eval.sh | ||
| push-to-store.sh | ||
| readfile-context.builder.sh | ||
| readfile-context.nix | ||
| readfile-context.sh | ||
| recursive.sh | ||
| referrers.sh | ||
| remote-builds.nix | ||
| remote-store.sh | ||
| repair.sh | ||
| repl.sh | ||
| restricted.nix | ||
| restricted.sh | ||
| search.nix | ||
| search.sh | ||
| secure-drv-outputs.nix | ||
| secure-drv-outputs.sh | ||
| selfref-gc.sh | ||
| setuid.nix | ||
| shell-hello.nix | ||
| shell.nix | ||
| shell.sh | ||
| shell.shebang.rb | ||
| shell.shebang.sh | ||
| signing.sh | ||
| simple-failing.nix | ||
| simple.builder.sh | ||
| simple.nix | ||
| simple.sh | ||
| sourcehut-flakes.nix | ||
| ssh-relay.sh | ||
| store-ping.sh | ||
| structured-attrs-shell.nix | ||
| structured-attrs.nix | ||
| structured-attrs.sh | ||
| substitute-with-invalid-ca.sh | ||
| suggestions.sh | ||
| tarball.sh | ||
| timeout.nix | ||
| timeout.sh | ||
| undefined-variable.nix | ||
| user-envs.builder.sh | ||
| user-envs.nix | ||
| user-envs.sh | ||
| why-depends.sh | ||
| zstd.sh | ||