nixide/nci.nix
Robert Hensing 6110414520 Add automatic C library input propagation workaround
Automatically adds Nix C library build inputs based on which nix-bindings
crates are dependencies, working around missing native input propagation
in nix-cargo-integration.

The workaround inspects the dreamLock to detect:
- If the crate being built is a nix-bindings crate (adds its own inputs)
- Direct dependencies on nix-bindings crates (adds their inputs)

The mapping is recursive via lazyAttrsOf, so depending on nix-bindings-flake
automatically brings in transitive C library dependencies.

Downstream consumers can extend the mapping for their own multi-crate
workspaces where crate A depends on crate B which depends on nix-bindings.
2026-01-13 15:31:50 +01:00

53 lines
1.8 KiB
Nix

{
perSystem =
{ config, ... }:
let
cfg = config.nix-bindings-rust;
in
{
# https://flake.parts/options/nix-cargo-integration
nci.projects.nix-bindings = {
path = ./.;
profiles = {
dev.drvConfig.env.RUSTFLAGS = "-D warnings";
release.runTests = true;
};
drvConfig = {
imports = [
# Downstream projects import this into depsDrvConfig instead
cfg.nciBuildConfig
];
# Extra settings for running the tests
mkDerivation = {
# Prepare the environment for Nix to work.
# Nix does not provide a suitable environment for running itself in
# the sandbox - not by default. We configure it to use a relocated store.
preCheck = ''
# nix needs a home directory
export HOME="$(mktemp -d $TMPDIR/home.XXXXXX)"
# configure a relocated store
store_data=$(mktemp -d $TMPDIR/store-data.XXXXXX)
export NIX_REMOTE="$store_data"
export NIX_BUILD_HOOK=
export NIX_CONF_DIR=$store_data/etc
export NIX_LOCALSTATE_DIR=$store_data/nix/var
export NIX_LOG_DIR=$store_data/nix/var/log/nix
export NIX_STATE_DIR=$store_data/nix/var/nix
echo "Configuring relocated store at $NIX_REMOTE..."
# Create nix.conf with experimental features enabled
mkdir -p "$NIX_CONF_DIR"
echo "experimental-features = ca-derivations flakes" > "$NIX_CONF_DIR/nix.conf"
# Init ahead of time, because concurrent initialization is flaky
${cfg.nixPackage}/bin/nix-store --init
echo "Store initialized."
'';
};
};
};
};
}