[Mamba POC] Bring in more conda logic

[jaimergp]

This PR implements a consolidated logic after studying the code in Solver._collect_all_metadata(), Solver._add_specs() and Solver._post_sat_handling. It's a reimplementation that doesn't use the SolverStateContainer features found in the Resolve instance they carry. More comments when needed, but it still needs to be documented thoroughly.

It's not perfect yet (conflict analysis is pending), but I am seeing more passing tests now.

This is an alternative implementation to the retry logic and history pinning found in #10946, #10947.

Let's see how many we can tackle now:

• tests/test_create.py

  • test_allow_softlinks
  • test_clone_offline_multichannel_with_untracked
  • test_conda_pip_interop_conda_editable_package -- this passes locally! :/
  • test_conda_recovery_of_pip_inconsistent_env
  • test_install_features
  • test_install_force_reinstall_flag
  • test_install_mkdir
  • test_list_with_pip_wheel
  • test_neutering_of_historic_specs
  • test_noarch_python_package_reinstall_on_pyver_change
  • test_noarch_python_package_without_entry_points
  • test_offline_with_empty_index_cache
  • test_package_optional_pinning
  • test_packages_not_found
  • test_pinned_override_with_explicit_spec
  • test_remove_all
  • test_remove_features
  • test_update_with_pinned_packages
  • test_create_env_default_packages

• tests/cli/test_cli_install.py

  • test_find_conflicts_called_once

• tests/conda_env/test_cli.py

  • test_update
  • test_update_env_json_output

• tests/core/test_solve.py

  • test_pinned_1
  • test_freeze_deps_1
  • test_prune_1
  • test_update_all_1
  • test_conda_downgrade
  • test_python2_update
  • test_fast_update_with_update_modifier_not_set
  • test_force_reinstall_1
  • test_channel_priority_churn_minimized
  • test_priority_1
  • test_features_solve_1
  • test_current_repodata_fallback

[jaimergp]

Down to 26 failing tests!

[jaimergp]

All green in both platforms, except four tiny issues on Windows:

Something about cleaning the index cache. They pass in isolation, but not with other tests in the same run. Fun stuff.

• tests/test_create.py::IntegrationTests::test_clean_index_cache
• tests/test_create.py::IntegrationTests::test_use_index_cache

Something about paths:

• tests/test_create.py::IntegrationTests::test_install_tarball_from_local_channel. This tries to create a Unix-like path for a Windows path and fails; e.g. C:\Some\Dir is turned into /C:/Some/Dir. Unclear if this is on us or mamba.
• tests/test_create.py::IntegrationTests::test_legacy_repodata. Fails with RuntimeError: Multi-download failed. and no more details. Probably path related as well. Unclear why it fails on Windows only, but this fake channel only has data for noarch so maybe Mamba is trying to download stuff from the win-64 directory and failing? Anyway, it says "legacy", we could skip :)

I will fix this first thing next week and merge for all green goodness.

[jaimergp]

Also note that I needed to use restricted unicode on Windows for now. This is being fixed in libmamba as we speak and we will be able to undo that workaround in the future.

And I also took split test_solvers.py tests into legacy and libsolv for CI purposes. LibSolv is only tested in the experimental-resolver.sh script. That way the CI checks tell us immediately if something is failing on legacy or not.

[jaimergp]

Looks like the index cache issue might be Windows leaving something open... Logs say:

DEBUG conda.gateways.disk.delete:unlink_or_rename_to_trash(136): renaming file path D:\Users\jrodriguez\Documents\conda\devenv\pkgs\cache\119df107.json to trash failed.  Output was: < empty >
WARNING conda.gateways.disk.delete:unlink_or_rename_to_trash(143): Could not remove or rename D:\Users\jrodriguez\Documents\conda\devenv\pkgs\cache\119df107.json.  Please remove this file manually (you may need to reboot to free file handles)

[jaimergp]

Is this the first time everything's green? 🔥

[jezdez]

This is ready. Thank you @jaimergp!