1 files changed, 113 insertions, 0 deletions
diff --git a/users/Profpatsch/nixpkgs-rewriter/default.nix b/users/Profpatsch/nixpkgs-rewriter/default.nix
new file mode 100644
index 000000000000..286530b03f94
--- /dev/null
+++ b/users/Profpatsch/nixpkgs-rewriter/default.nix
@@ -0,0 +1,113 @@
+{ depot, pkgs, ... }:
+let
+  inherit (depot.nix)
+    writeExecline
+    ;
+  inherit (depot.users.Profpatsch.lib)
+    debugExec
+    eprintf
+    ;
+
+  bins = depot.nix.getBins pkgs.coreutils [ "head" "shuf" ]
+      // depot.nix.getBins pkgs.jq [ "jq" ]
+      // depot.nix.getBins pkgs.findutils [ "xargs" ]
+      // depot.nix.getBins pkgs.gnused [ "sed" ]
+      ;
+
+  export-json-object = pkgs.writers.writePython3 "export-json-object" {} ''
+    import json
+    import sys
+    import os
+
+    d = json.load(sys.stdin)
+
+    if d == {}:
+        sys.exit(0)
+
+    for k, v in d.items():
+        os.environ[k] = str(v)
+
+    os.execvp(sys.argv[1], sys.argv[1:])
+  '';
+
+  meta-stdenv-lib = pkgs.writers.writeHaskell "meta-stdenv-lib" {
+    libraries = [
+      pkgs.haskellPackages.hnix
+      pkgs.haskellPackages.aeson
+    ];
+  } ./MetaStdenvLib.hs;
+
+  replace-between-lines = writeExecline "replace-between-lines" { readNArgs = 1; } [
+    "importas" "-ui" "file" "fileName"
+    "importas" "-ui" "from" "fromLine"
+    "importas" "-ui" "to" "toLine"
+    "if" [ eprintf "%s-%s\n" "$from" "$to" ]
+    (debugExec "adding lib")
+    bins.sed
+      "-e" "\${from},\${to} \${1}"
+      "-i" "$file"
+  ];
+
+  add-lib-if-necessary = writeExecline "add-lib-if-necessary" { readNArgs = 1; } [
+    "pipeline" [ meta-stdenv-lib "$1" ]
+     export-json-object
+     # first replace any stdenv.lib mentions in the arg header
+     # if this is not done, the replace below kills these.
+     # Since we want it anyway ultimately, let’s do it here.
+     "if" [ replace-between-lines "s/stdenv\.lib/lib/" ]
+     # then add the lib argument
+     # (has to be before stdenv, otherwise default arguments might be in the way)
+     replace-between-lines "s/stdenv/lib, stdenv/"
+  ];
+
+  metaString = ''meta = with stdenv.lib; {'';
+
+  replace-stdenv-lib = pkgs.writers.writeBash "replace-stdenv-lib" ''
+    set -euo pipefail
+    sourceDir="$1"
+    for file in $(
+      ${pkgs.ripgrep}/bin/rg \
+        --files-with-matches \
+        --fixed-strings \
+        -e '${metaString}' \
+        "$sourceDir"
+    )
+    do
+      echo "replacing stdenv.lib meta in $file" >&2
+      ${bins.sed} -e '/${metaString}/ s/stdenv.lib/lib/' \
+          -i "$file"
+      ${add-lib-if-necessary} "$file"
+    done
+  '';
+
+  instantiate-nixpkgs-randomly = writeExecline "instantiate-nixpkgs-randomly" { readNArgs = 1; } [
+    "export" "NIXPKGS_ALLOW_BROKEN" "1"
+    "export" "NIXPKGS_ALLOW_UNFREE" "1"
+    "export" "NIXPKGS_ALLOW_INSECURE" "1"
+    "export" "NIXPKGS_ALLOW_UNSUPPORTED_SYSTEM" "1"
+    "pipeline" [
+      "nix"
+        "eval"
+        "--raw"
+        ''(
+          let pkgs = import ''${1} {};
+          in builtins.toJSON (builtins.attrNames pkgs)
+        )''
+    ]
+    "pipeline" [ bins.jq "-r" ".[]" ]
+    "pipeline" [ bins.shuf ]
+    "pipeline" [ bins.head "-n" "1000" ]
+    bins.xargs "-I" "{}" "-n1"
+    "if" [ eprintf "instantiating %s\n" "{}" ]
+    "nix-instantiate" "$1" "-A" "{}"
+  ];
+
+in {
+  inherit
+   instantiate-nixpkgs-randomly
+  # requires hnix, which we don’t want in tvl for now
+  # uncomment manually if you want to use it.
+  #   meta-stdenv-lib
+  #   replace-stdenv-lib
+    ;
+}