rustPackages.buildRustPackages: allow one level of introspection before applying __attrsFailEvaluation

[philiptaron]

Description of changes

• Tracking issue: remove and mitigate __attrsFailEvaluation #324619

The test (nix-build pkgs/test/release/default.nix) continues to pass.

These lines were added in #269356.

I learned this trick from this file, where it's used to allow one level of inspection.

nixpkgs/pkgs/top-level/perl-packages.nix

Line 26 in 1b87ff2

perlPackages = self // { perlPackages = self.perlPackages // { __attrsFailEvaluation = true; }; };

New derivations reported:

--- /dev/fd/63	2024-07-04 11:37:43.896690011 -0700
+++ /dev/fd/62	2024-07-04 11:37:43.896690011 -0700
@@ -82087,8 +82087,26 @@
   "russ",
   "rust.packages.prebuilt.cargo",
   "rust.packages.prebuilt.rustc",
   "rust.packages.prebuilt.rustc-unwrapped",
+  "rust.packages.stable.buildRustPackages.cargo",
+  "rust.packages.stable.buildRustPackages.cargo-auditable",
+  "rust.packages.stable.buildRustPackages.cargo-auditable-cargo-wrapper",
+  "rust.packages.stable.buildRustPackages.clippy",
+  "rust.packages.stable.buildRustPackages.rustPlatform.bindgenHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.cargoBuildHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.cargoCheckHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.cargoInstallHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.cargoNextestHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.cargoSetupHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.maturinBuildHook",
+  "rust.packages.stable.buildRustPackages.rustPlatform.rust.cargo",
+  "rust.packages.stable.buildRustPackages.rustPlatform.rust.rustc",
+  "rust.packages.stable.buildRustPackages.rustPlatform.rustLibSrc",
+  "rust.packages.stable.buildRustPackages.rustPlatform.rustcSrc",
+  "rust.packages.stable.buildRustPackages.rustc",
+  "rust.packages.stable.buildRustPackages.rustc-unwrapped",
+  "rust.packages.stable.buildRustPackages.rustfmt",
   "rust.packages.stable.cargo",
   "rust.packages.stable.cargo-auditable",
   "rust.packages.stable.cargo-auditable-cargo-wrapper",
   "rust.packages.stable.clippy",
@@ -82119,8 +82137,26 @@
   "rust-motd",
   "rust-petname",
   "rust-script",
   "rust-traverse",
+  "rustPackages.buildRustPackages.cargo",
+  "rustPackages.buildRustPackages.cargo-auditable",
+  "rustPackages.buildRustPackages.cargo-auditable-cargo-wrapper",
+  "rustPackages.buildRustPackages.clippy",
+  "rustPackages.buildRustPackages.rustPlatform.bindgenHook",
+  "rustPackages.buildRustPackages.rustPlatform.cargoBuildHook",
+  "rustPackages.buildRustPackages.rustPlatform.cargoCheckHook",
+  "rustPackages.buildRustPackages.rustPlatform.cargoInstallHook",
+  "rustPackages.buildRustPackages.rustPlatform.cargoNextestHook",
+  "rustPackages.buildRustPackages.rustPlatform.cargoSetupHook",
+  "rustPackages.buildRustPackages.rustPlatform.maturinBuildHook",
+  "rustPackages.buildRustPackages.rustPlatform.rust.cargo",
+  "rustPackages.buildRustPackages.rustPlatform.rust.rustc",
+  "rustPackages.buildRustPackages.rustPlatform.rustLibSrc",
+  "rustPackages.buildRustPackages.rustPlatform.rustcSrc",
+  "rustPackages.buildRustPackages.rustc",
+  "rustPackages.buildRustPackages.rustc-unwrapped",
+  "rustPackages.buildRustPackages.rustfmt",
   "rustPackages.cargo",
   "rustPackages.cargo-auditable",
   "rustPackages.cargo-auditable-cargo-wrapper",
   "rustPackages.clippy",
@@ -82137,8 +82173,26 @@
   "rustPackages.rustPlatform.rustcSrc",
   "rustPackages.rustc",
   "rustPackages.rustc-unwrapped",
   "rustPackages.rustfmt",
+  "rustPackages_1_78.buildRustPackages.cargo",
+  "rustPackages_1_78.buildRustPackages.cargo-auditable",
+  "rustPackages_1_78.buildRustPackages.cargo-auditable-cargo-wrapper",
+  "rustPackages_1_78.buildRustPackages.clippy",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.bindgenHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.cargoBuildHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.cargoCheckHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.cargoInstallHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.cargoNextestHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.cargoSetupHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.maturinBuildHook",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.rust.cargo",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.rust.rustc",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.rustLibSrc",
+  "rustPackages_1_78.buildRustPackages.rustPlatform.rustcSrc",
+  "rustPackages_1_78.buildRustPackages.rustc",
+  "rustPackages_1_78.buildRustPackages.rustc-unwrapped",
+  "rustPackages_1_78.buildRustPackages.rustfmt",
   "rustPackages_1_78.cargo",
   "rustPackages_1_78.cargo-auditable",
   "rustPackages_1_78.cargo-auditable-cargo-wrapper",
   "rustPackages_1_78.clippy",
@@ -82169,8 +82223,26 @@
   "rustPlatform.rustcSrc",
   "rust_1_78.packages.prebuilt.cargo",
   "rust_1_78.packages.prebuilt.rustc",
   "rust_1_78.packages.prebuilt.rustc-unwrapped",
+  "rust_1_78.packages.stable.buildRustPackages.cargo",
+  "rust_1_78.packages.stable.buildRustPackages.cargo-auditable",
+  "rust_1_78.packages.stable.buildRustPackages.cargo-auditable-cargo-wrapper",
+  "rust_1_78.packages.stable.buildRustPackages.clippy",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.bindgenHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.cargoBuildHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.cargoCheckHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.cargoInstallHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.cargoNextestHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.cargoSetupHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.maturinBuildHook",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.rust.cargo",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.rust.rustc",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.rustLibSrc",
+  "rust_1_78.packages.stable.buildRustPackages.rustPlatform.rustcSrc",
+  "rust_1_78.packages.stable.buildRustPackages.rustc",
+  "rust_1_78.packages.stable.buildRustPackages.rustc-unwrapped",
+  "rust_1_78.packages.stable.buildRustPackages.rustfmt",
   "rust_1_78.packages.stable.cargo",
   "rust_1_78.packages.stable.cargo-auditable",
   "rust_1_78.packages.stable.cargo-auditable-cargo-wrapper",
   "rust_1_78.packages.stable.clippy",

Things done

• Tested, as applicable:
  • nix-build pkgs/test/release/default.nix
• Fits CONTRIBUTING.md.

[infinisil]

Tested nix-build pkgs/test/release when merging this into current master, still works, so this LGTM!