feat(users/edef/refscan): high-performance Nix reference scanner r/5636

Research-grade code, treat with care.

Change-Id: I99804df93e64101ef24928238ef0a8a02b59c2aa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7686
Reviewed-by: edef <edef@edef.eu>
Tested-by: BuildkiteCI

1 files changed, 6 insertions, 0 deletions

diff --git a/users/edef/refscan/testdata/generate.sh b/users/edef/refscan/testdata/generate.sh
new file mode 100755
index 000000000000..02d8c4056789
--- /dev/null
+++ b/users/edef/refscan/testdata/generate.sh
@@ -0,0 +1,6 @@
+#! /usr/bin/env bash
+set -euo pipefail
+
+drv=$(nix-instantiate '<nixpkgs>' -A ghc)
+nix --extra-experimental-features nix-command show-derivation -r "$drv" | jq -r '.[] | .outputs[].path, .inputSrcs[]' | sort -u | cut -d/ -f4 | cut -d- -f1 > maxrefs
+nix-store --dump "$(nix-build "$drv")" > nar