Build failure: python313Packages.cartopy

[mobergmann]

Nixpkgs version

• Unstable (26.05)

Steps to reproduce

nix develop for this flake:

{
  inputs = { nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable"; };

  outputs = { self, nixpkgs }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };
    in {
      devShells.${system}.default = pkgs.mkShell {
        packages = with pkgs; [ python313Packages.cartopy ];
      };
    };
}

You can change python313Packages.cartopy to any of the list below and it wont build.

• python314Packages.cartopy
• python313Packages.cartopy
• python312Packages.cartopy

Can Hydra reproduce this build failure?

Yes, Hydra can reproduce this build failure.

Link to Hydra build job

https://hydra.nixos.org/build/327874596

Relevant log output

warning: Git tree '/home/mobergmann/Source/mobile-communication' is dirty
evaluating derivation 'git+file:///home/mobergmann/Source/mobile-communication#devShells.x86_64-linux.default'
error: Cannot build '/nix/store/pd9f8y4q0i5jxn97avgg7gn0wpcm0w7w-python3.14-cartopy-0.25.0.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/4qwwrp9wjwvxc80lk04plpkxxd6yqfg0-python3.14-cartopy-0.25.0-dist
         /nix/store/l0py3xnlfx47l8nznjjr0lry5kicc59r-python3.14-cartopy-0.25.0
       Last 25 log lines:
       > FAILED tests/crs/test_transverse_mercator.py::TestTransverseMercator::test_osgb_vals[False] - AssertionError:
       > FAILED tests/crs/test_transverse_mercator.py::TestOSGB::test_default[True] - AssertionError:
       > FAILED tests/crs/test_transverse_mercator.py::TestOSGB::test_default[False] - AssertionError:
       > FAILED tests/crs/test_transverse_mercator.py::TestOSNI::test_default[True] - AssertionError:
       > FAILED tests/crs/test_transverse_mercator.py::TestOSNI::test_default[False] - AssertionError:
       > FAILED tests/mpl/test_axes.py::test_geoaxes_no_subslice - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_axes.py::test_geoaxes_set_boundary_clipping - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_contour.py::test_plot_after_contour_doesnt_shrink[contour] - AssertionError:
       > FAILED tests/mpl/test_gridliner.py::test_gridliner_labels_zoom - assert [<cartopy.mpl...b7080c0>, ...] == [<cartopy.mpl...b7080c0>, ...]
       > FAILED tests/mpl/test_images.py::test_imshow - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_images.py::test_stock_img - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_images.py::test_pil_Image - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_images.py::test_background_img - Failed: Error: Image files did not match.
       > FAILED tests/mpl/test_mpl_integration.py::test_cursor_values - AssertionError: assert b'-181.5, 50 ... 178.500000E)' == b'-181.5, 50 ... 1...
       > FAILED tests/mpl/test_pseudo_color.py::test_pcolormesh_datalim - AssertionError:
       > FAILED tests/mpl/test_set_extent.py::test_extents - AssertionError:
       > FAILED tests/mpl/test_set_extent.py::test_get_extent - AssertionError:
       > FAILED tests/mpl/test_ticker.py::test_LatitudeFormatter_mercator - AssertionError: assert ['79.8166°S',....7746°N', ...] == ['80°S', '60°..., ...
       > FAILED tests/test_crs_transform_vectors.py::TestTransformVectors::test_invalid_y_domain - AssertionError:
       > FAILED tests/test_crs_transform_vectors.py::TestTransformVectors::test_invalid_xy_domain_corner - AssertionError:
       > FAILED tests/test_polygon.py::TestMisc::test_infinite_loop_bounds[InterruptedGoodeHomolosine] - assert 3148724.315906706 == nan ± ???
       > FAILED tests/test_polygon.py::TestMisc::test_infinite_loop_bounds[Mollweide] - assert 0.0 == nan ± ???
       > FAILED tests/test_polygon.py::TestMisc::test_tiny_point_between_boundary_points - AssertionError: Got area 85832.84574015415, expecting ~81336
       > FAILED tests/test_vector_transform.py::Test_vector_scalar_to_grid::test_with_transform - AssertionError:
       > = 39 failed, 625 passed, 7 skipped, 219 deselected, 2 xfailed, 7 warnings in 14.41s =
       For full logs, run:
         nix log /nix/store/pd9f8y4q0i5jxn97avgg7gn0wpcm0w7w-python3.14-cartopy-0.25.0.drv
error: Cannot build '/nix/store/psaav1kgj32yc9pzcwg1clwiyz4vvzjg-nix-shell-env.drv'.
       Reason: 1 dependency failed.
       Output paths:
         /nix/store/2wlg17z1xmbypm0fgs9sglgi1vhmjsar-nix-shell-env

Additional context

No response

System metadata

• system: "x86_64-linux"
• host os: Linux 6.12.85, NixOS, 25.11 (Xantusia), 25.11.20260501.26ef669
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.31.4
• channels(root): "home-manager-24.05.tar.gz, home-manager-unstable, nixos-24.05, nixos-unstable"
• nixpkgs: /nix/store/zg0fzjv0hmm0g6jdbqcf6b81b4hrqi5p-source

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[jackrosenberg]

linked to SciTools/cartopy#2653 and SciTools/cartopy#2634