# Tests for the Python interpreters, package sets and environments.
#
# Each Python interpreter has a `passthru.tests` which is the attribute set
# returned by this function. For example, for Python 3 the tests are run with
#
# $ nix-build -A python3.tests
#
{
  stdenv,
  python,
  runCommand,
  lib,
  callPackage,
  pkgs,
}:

let
  # Test whether the interpreter behaves in the different types of environments
  # we aim to support.
  environmentTests =
    let
      envs =
        let
          inherit python;
          pythonEnv = python.withPackages (ps: with ps; [ ]);
          pythonVirtualEnv =
            if python.isPy3k then
              python.withPackages (ps: with ps; [ virtualenv ])
            else
              python.buildEnv.override {
                extraLibs = with python.pkgs; [ virtualenv ];
                # Collisions because of namespaces __init__.py
                ignoreCollisions = true;
              };
        in
        {
          # Plain Python interpreter
          plain = rec {
            env = python;
            interpreter = env.interpreter;
            is_venv = "False";
            is_nixenv = "False";
            is_virtualenv = "False";
          };
        }
        // lib.optionalAttrs (!python.isPyPy && !stdenv.isDarwin) {
          # Use virtualenv from a Nix env.
          # Fails on darwin with
          #   virtualenv: error: argument dest: the destination . is not write-able at /nix/store
          nixenv-virtualenv = rec {
            env = runCommand "${python.name}-virtualenv" { } ''
              ${pythonVirtualEnv.interpreter} -m virtualenv venv
              mv venv $out
            '';
            interpreter = "${env}/bin/${python.executable}";
            is_venv = "False";
            is_nixenv = "True";
            is_virtualenv = "True";
          };
        }
        // lib.optionalAttrs (python.implementation != "graal") {
          # Python Nix environment (python.buildEnv)
          nixenv = rec {
            env = pythonEnv;
            interpreter = env.interpreter;
            is_venv = "False";
            is_nixenv = "True";
            is_virtualenv = "False";
          };
        }
        // lib.optionalAttrs (python.isPy3k && (!python.isPyPy)) {
          # Venv built using plain Python
          # Python 2 does not support venv
          # TODO: PyPy executable name is incorrect, it should be pypy-c or pypy-3c instead of pypy and pypy3.
          plain-venv = rec {
            env = runCommand "${python.name}-venv" { } ''
              ${python.interpreter} -m venv $out
            '';
            interpreter = "${env}/bin/${python.executable}";
            is_venv = "True";
            is_nixenv = "False";
            is_virtualenv = "False";
          };

        }
        // lib.optionalAttrs (python.pythonAtLeast "3.8") {
          # Venv built using Python Nix environment (python.buildEnv)
          # TODO: Cannot create venv from a  nix env
          # Error: Command '['/nix/store/ddc8nqx73pda86ibvhzdmvdsqmwnbjf7-python3-3.7.6-venv/bin/python3.7', '-Im', 'ensurepip', '--upgrade', '--default-pip']' returned non-zero exit status 1.
          nixenv-venv = rec {
            env = runCommand "${python.name}-venv" { } ''
              ${pythonEnv.interpreter} -m venv $out
            '';
            interpreter = "${env}/bin/${pythonEnv.executable}";
            is_venv = "True";
            is_nixenv = "True";
            is_virtualenv = "False";
          };
        };

      testfun =
        name: attrs:
        runCommand "${python.name}-tests-${name}" ({ inherit (python) pythonVersion; } // attrs) ''
          cp -r ${./tests/test_environments} tests
          chmod -R +w tests
          substituteAllInPlace tests/test_python.py
          ${attrs.interpreter} -m unittest discover --verbose tests #/test_python.py
          mkdir $out
          touch $out/success
        '';

    in
    lib.mapAttrs testfun envs;

  # Integration tests involving the package set.
  # All PyPy package builds are broken at the moment
  integrationTests = lib.optionalAttrs (!python.isPyPy) (
    lib.optionalAttrs (python.isPy3k && !stdenv.isDarwin) {
      # darwin has no split-debug
      cpython-gdb = callPackage ./tests/test_cpython_gdb { interpreter = python; };
    }
    // lib.optionalAttrs (python.pythonAtLeast "3.7") {
      # Before the addition of NIX_PYTHONPREFIX mypy was broken with typed packages
      nix-pythonprefix-mypy = callPackage ./tests/test_nix_pythonprefix { interpreter = python; };
      # Make sure tkinter is importable. See https://github.com/NixOS/nixpkgs/issues/238990
      tkinter = callPackage ./tests/test_tkinter { interpreter = python; };
    }
  );

  # Tests to ensure overriding works as expected.
  overrideTests =
    let
      extension = self: super: { foobar = super.numpy; };
      # `pythonInterpreters.pypy39_prebuilt` does not expose an attribute
      # name (is not present in top-level `pkgs`).
      is_prebuilt = python: python.pythonAttr == null;
    in
    lib.optionalAttrs (python.isPy3k) (
      {
        test-packageOverrides =
          let
            myPython =
              let
                self = python.override {
                  packageOverrides = extension;
                  inherit self;
                };
              in
              self;
          in
          assert myPython.pkgs.foobar == myPython.pkgs.numpy;
          myPython.withPackages (ps: with ps; [ foobar ]);
        # overrideScope is broken currently
        # test-overrideScope = let
        #  myPackages = python.pkgs.overrideScope extension;
        # in assert myPackages.foobar == myPackages.numpy; myPackages.python.withPackages(ps: with ps; [ foobar ]);
        #
        # Have to skip prebuilt python as it's not present in top-level
        # `pkgs` as an attribute.
      }
      // lib.optionalAttrs (python ? pythonAttr && !is_prebuilt python) {
        # Test applying overrides using pythonPackagesOverlays.
        test-pythonPackagesExtensions =
          let
            pkgs_ = pkgs.extend (
              final: prev: {
                pythonPackagesExtensions = prev.pythonPackagesExtensions ++ [
                  (python-final: python-prev: { foo = python-prev.setuptools; })
                ];
              }
            );
          in
          pkgs_.${python.pythonAttr}.pkgs.foo;
      }
    );

  condaTests =
    let
      requests = callPackage (
        {
          autoPatchelfHook,
          fetchurl,
          pythonCondaPackages,
        }:
        python.pkgs.buildPythonPackage {
          pname = "requests";
          version = "2.24.0";
          format = "other";
          src = fetchurl {
            url = "https://repo.anaconda.com/pkgs/main/noarch/requests-2.24.0-py_0.tar.bz2";
            sha256 = "02qzaf6gwsqbcs69pix1fnjxzgnngwzvrsy65h1d521g750mjvvp";
          };
          nativeBuildInputs =
            [ autoPatchelfHook ]
            ++ (with python.pkgs; [
              condaUnpackHook
              condaInstallHook
            ]);
          buildInputs = [ pythonCondaPackages.condaPatchelfLibs ];
          propagatedBuildInputs = with python.pkgs; [
            chardet
            idna
            urllib3
            certifi
          ];
        }
      ) { };
      pythonWithRequests = requests.pythonModule.withPackages (ps: [ requests ]);
    in
    lib.optionalAttrs (python.isPy3k && stdenv.isLinux) {
      condaExamplePackage = runCommand "import-requests" { } ''
        ${pythonWithRequests.interpreter} -c "import requests" > $out
      '';
    };

in
lib.optionalAttrs (stdenv.hostPlatform == stdenv.buildPlatform) (
  environmentTests // integrationTests // overrideTests // condaTests
)