From 3dcde1c342e613853087bc35d66fd4a769cc3f06 Mon Sep 17 00:00:00 2001 From: John Ericson Date: Fri, 3 Feb 2023 08:31:25 -0500 Subject: [PATCH 1/2] zlib: Use `finalAttrs` instead of `rec` --- pkgs/development/libraries/zlib/default.nix | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/pkgs/development/libraries/zlib/default.nix b/pkgs/development/libraries/zlib/default.nix index 52654b6541e3..718d34b19449 100644 --- a/pkgs/development/libraries/zlib/default.nix +++ b/pkgs/development/libraries/zlib/default.nix @@ -21,11 +21,13 @@ assert shared || static; assert splitStaticOutput -> static; -stdenv.mkDerivation rec { +stdenv.mkDerivation (finalAttrs: { pname = "zlib"; version = "1.2.13"; - src = fetchurl { + src = let + inherit (finalAttrs) version; + in fetchurl { urls = [ # This URL works for 1.2.13 only; hopefully also for future releases. "https://github.com/madler/zlib/releases/download/v${version}/zlib-${version}.tar.gz" @@ -131,4 +133,4 @@ stdenv.mkDerivation rec { license = licenses.zlib; platforms = platforms.all; }; -} +}) From 6e4a1b18d995605b95365387d3752e279a2c2ccc Mon Sep 17 00:00:00 2001 From: John Ericson Date: Thu, 2 Feb 2023 23:49:15 -0500 Subject: [PATCH 2/2] meta.pkgConfigModules: Init convention See docs. Follow-up work: - Existing packages should be converted - `defaultPkgConfigPackages` should assert on `meta.pkgConfigModules` and let `tests.pkg-config` alone test the build results. CC @sternenseemann Co-authored-by: Robert Hensing --- .../pkg-config.section.md | 48 +++++++++++++++++-- pkgs/build-support/testers/default.nix | 1 + .../testers/testMetaPkgConfig/tester.nix | 14 ++++++ pkgs/development/libraries/zlib/default.nix | 4 ++ pkgs/stdenv/generic/check-meta.nix | 1 + 5 files changed, 65 insertions(+), 3 deletions(-) create mode 100644 pkgs/build-support/testers/testMetaPkgConfig/tester.nix diff --git a/doc/languages-frameworks/pkg-config.section.md b/doc/languages-frameworks/pkg-config.section.md index ee0a471be3e5..eecc84b4c1aa 100644 --- a/doc/languages-frameworks/pkg-config.section.md +++ b/doc/languages-frameworks/pkg-config.section.md @@ -4,6 +4,48 @@ Nixpkgs provides a couple of facilities for working with this tool. - - A [setup hook](#setup-hook-pkg-config) bundled with in the `pkg-config` package, to bring a derivation's declared build inputs into the environment. - - The [`validatePkgConfig` setup hook](https://nixos.org/manual/nixpkgs/stable/#validatepkgconfig), for packages that provide pkg-config modules. - - The `defaultPkgConfigPackages` package set: a set of aliases, named after the modules they provide. This is meant to be used by language-to-nix integrations. Hand-written packages should use the normal Nixpkgs attribute name instead. +## Writing packages providing pkg-config modules + +Packages should set `meta.pkgConfigProvides` with the list of package config modules they provide. +They should also use `testers.testMetaPkgConfig` to check that the final built package matches that list. +Additionally, the [`validatePkgConfig` setup hook](https://nixos.org/manual/nixpkgs/stable/#validatepkgconfig), will do extra checks on to-be-installed pkg-config modules. + +A good example of all these things is zlib: + +``` +{ pkg-config, testers, ... }: + +stdenv.mkDerivation (finalAttrs: { + ... + + nativeBuildInputs = [ pkg-config validatePkgConfig ]; + + passthru.tests.pkg-config = testers.testMetaPkgConfig finalAttrs.finalPackage; + + meta = { + ... + pkgConfigModules = [ "zlib" ]; + }; +}) +``` + +## Accessing packages via pkg-config module name + +### Within Nixpkgs + +A [setup hook](#setup-hook-pkg-config) is bundled in the `pkg-config` package to bring a derivation's declared build inputs into the environment. +This will populate environment variables like `PKG_CONFIG_PATH`, `PKG_CONFIG_PATH_FOR_BUILD`, and `PKG_CONFIG_PATH_HOST` based on: + + - how `pkg-config` itself is depended upon + + - how other dependencies are depended upon + +For more details see the section on [specifying dependencies in general](#ssec-stdenv-dependencies). + +Normal pkg-config commands to look up dependencies by name will then work with those environment variables defined by the hook. + +### Externally + +The `defaultPkgConfigPackages` package set is a set of aliases, named after the modules they provide. +This is meant to be used by language-to-nix integrations. +Hand-written packages should use the normal Nixpkgs attribute name instead. diff --git a/pkgs/build-support/testers/default.nix b/pkgs/build-support/testers/default.nix index 15694162edde..542133dd959a 100644 --- a/pkgs/build-support/testers/default.nix +++ b/pkgs/build-support/testers/default.nix @@ -123,4 +123,5 @@ hasPkgConfigModule = callPackage ./hasPkgConfigModule/tester.nix { }; + testMetaPkgConfig = callPackage ./testMetaPkgConfig/tester.nix { }; } diff --git a/pkgs/build-support/testers/testMetaPkgConfig/tester.nix b/pkgs/build-support/testers/testMetaPkgConfig/tester.nix new file mode 100644 index 000000000000..bee97ace1409 --- /dev/null +++ b/pkgs/build-support/testers/testMetaPkgConfig/tester.nix @@ -0,0 +1,14 @@ +{ lib, runCommand, testers }: + +package: + +runCommand "check-meta-pkg-config-modules-for-${package.name}" { + meta = { + description = "Test whether ${package.name} exposes all pkg-config modules ${toString package.meta.pkgConfigModules}"; + }; + dependsOn = map + (moduleName: testers.hasPkgConfigModule { inherit package moduleName; }) + package.meta.pkgConfigModules; +} '' + echo "found all of ${toString package.meta.pkgConfigModules}" > "$out" +'' diff --git a/pkgs/development/libraries/zlib/default.nix b/pkgs/development/libraries/zlib/default.nix index 718d34b19449..4ca77d56fca9 100644 --- a/pkgs/development/libraries/zlib/default.nix +++ b/pkgs/development/libraries/zlib/default.nix @@ -8,6 +8,7 @@ # the `.pc` file lists only the main output's lib dir. # If false, and if `{ static = true; }`, the .a stays in the main output. , splitStaticOutput ? shared && static +, testers }: # Without either the build will actually still succeed because the build @@ -127,10 +128,13 @@ stdenv.mkDerivation (finalAttrs: { "SHARED_MODE=1" ]; + passthru.tests.pkg-config = testers.testMetaPkgConfig finalAttrs.finalPackage; + meta = with lib; { homepage = "https://zlib.net"; description = "Lossless data-compression library"; license = licenses.zlib; platforms = platforms.all; + pkgConfigModules = [ "zlib" ]; }; }) diff --git a/pkgs/stdenv/generic/check-meta.nix b/pkgs/stdenv/generic/check-meta.nix index 751e19d1681a..9d99be2a0203 100644 --- a/pkgs/stdenv/generic/check-meta.nix +++ b/pkgs/stdenv/generic/check-meta.nix @@ -271,6 +271,7 @@ let sourceProvenance = listOf lib.types.attrs; maintainers = listOf (attrsOf anything); # TODO use the maintainer type from lib/tests/maintainer-module.nix priority = int; + pkgConfigModules = listOf str; platforms = listOf (either str (attrsOf anything)); # see lib.meta.platformMatch hydraPlatforms = listOf str; broken = bool;