🧹 Test Suite Cleanup: Permanent Issue

[abn]

Hi there! This issue is a permanent issue dedicated as a hub for efforts to improve the quality of the test suite. If you have questions talk to the community on our Discord server.

If you have a question about a particular issue, or pull request just tag @python-poetry/triage in a comment.

This is a great issue to work on if you are new to the Poetry code base and want to start contributing. Over the years the Poetry test suite has grown significantly -- this means that there is significant a amount of code duplication that is hard to maintain and inefficient .

If you are submitting a pull request associated with this, please keep the pull requests small and modular. This means, do not do too much in one PR and try to do only closely related changes in on PR. Additionally, make sure you add Relates-to: (not Closes: or Fixes: or Resolves:) to your PR description.

Relates-to: #3155

If this is your first contribution here, please refer to #3061 before continuing.

Ongoing Improvements

Convert reused code/logic into fixtures

There is a significant amount of code and data duplication in the test suite that can be converted to pytest fixtures.

Adding coverage

There are certain code paths within the codebase that may not necessarily be covered within the test suite. You can.

a) Find them, and raise an issue to cover them.
b) (a) and also write some tests.

Known missing:

• poetry build command.
• Add test coverage for tests/helpers.py #9161

Improve Parallel Safety

Presently, because a lot of tests generate and cleanup package metadata, or share resources the tests suite is not parallel execution safe. Any improvements towards this goal is always welcome. Most of this will be covered by proper use of fixtures, but identifying shared file resources being used and working on on-write copies would go a long way in this goal.

[Secrus]

UPDATED: January 27th '24
As of today, our test coverage looks like this (skipped files with 100% coverage):

Name                                                         Stmts   Miss  Cover
--------------------------------------------------------------------------------
src/poetry/__main__.py                                           5      5     0%
src/poetry/config/config.py                                    184      3    98%
src/poetry/config/config_source.py                               7      2    71%
src/poetry/config/dict_config_source.py                         29      1    97%
src/poetry/config/file_config_source.py                         57     38    33%
src/poetry/console/application.py                              205     11    95%
src/poetry/console/command_loader.py                             9      1    89%
src/poetry/console/commands/add.py                             133      3    98%
src/poetry/console/commands/cache/clear.py                      49      9    82%
src/poetry/console/commands/check.py                            78      2    97%
src/poetry/console/commands/command.py                          27      3    89%
src/poetry/console/commands/config.py                          166      7    96%
src/poetry/console/commands/debug/resolve.py                    81     13    84%
src/poetry/console/commands/env/info.py                         36      2    94%
src/poetry/console/commands/env/list.py                         20      1    95%
src/poetry/console/commands/env/remove.py                       26      1    96%
src/poetry/console/commands/env/use.py                          16      2    88%
src/poetry/console/commands/init.py                            244     12    95%
src/poetry/console/commands/installer_command.py                18      3    83%
src/poetry/console/commands/new.py                              44      3    93%
src/poetry/console/commands/publish.py                          27      6    78%
src/poetry/console/commands/remove.py                           72      9    88%
src/poetry/console/commands/run.py                              47      2    96%
src/poetry/console/commands/self/install.py                     12      1    92%
src/poetry/console/commands/self/self_command.py                72      2    97%
src/poetry/console/commands/self/show/__init__.py               15      4    73%
src/poetry/console/commands/self/show/plugins.py                64      2    97%
src/poetry/console/commands/self/update.py                      27      2    93%
src/poetry/console/commands/show.py                            286     13    95%
src/poetry/console/commands/source/add.py                       74      3    96%
src/poetry/console/commands/version.py                          59      2    97%
src/poetry/console/io/inputs/run_argv_input.py                  50      7    86%
src/poetry/console/logging/formatters/builder_formatter.py      14      9    36%
src/poetry/console/logging/formatters/formatter.py               4      1    75%
src/poetry/console/logging/io_formatter.py                      19     11    42%
src/poetry/console/logging/io_handler.py                        17      9    47%
src/poetry/factory.py                                          199      9    95%
src/poetry/inspection/info.py                                  294     20    93%
src/poetry/inspection/lazy_wheel.py                            294     23    92%
src/poetry/installation/chef.py                                112      3    97%
src/poetry/installation/chooser.py                              86     13    85%
src/poetry/installation/executor.py                            530     57    89%
src/poetry/installation/installer.py                           223     11    95%
src/poetry/installation/operations/install.py                   17      2    88%
src/poetry/installation/operations/operation.py                 39      8    79%
src/poetry/installation/operations/uninstall.py                 17      2    88%
src/poetry/installation/operations/update.py                    28      6    79%
src/poetry/installation/wheel_installer.py                      53      6    89%
src/poetry/layouts/__init__.py                                   8      1    88%
src/poetry/layouts/layout.py                                   111      5    95%
src/poetry/locations.py                                         24      7    71%
src/poetry/masonry/api.py                                        7      7     0%
src/poetry/masonry/builders/editable.py                        140     16    89%
src/poetry/mixology/failure.py                                 136     31    77%
src/poetry/mixology/incompatibility.py                         250     38    85%
src/poetry/mixology/incompatibility_cause.py                    37      3    92%
src/poetry/mixology/partial_solution.py                         93      3    97%
src/poetry/mixology/term.py                                     82     10    88%
src/poetry/mixology/version_solver.py                          217      1    99%
src/poetry/packages/dependency_package.py                       29      2    93%
src/poetry/packages/direct_origin.py                            50      3    94%
src/poetry/packages/locker.py                                  279      6    98%
src/poetry/plugins/base_plugin.py                                8      1    88%
src/poetry/plugins/plugin.py                                     9      1    89%
src/poetry/plugins/plugin_manager.py                            36      1    97%
src/poetry/publishing/uploader.py                              164     17    90%
src/poetry/puzzle/provider.py                                  432     46    89%
src/poetry/puzzle/solver.py                                    171      4    98%
src/poetry/pyproject/toml.py                                    35      1    97%
src/poetry/repositories/cached_repository.py                    32      7    78%
src/poetry/repositories/http_repository.py                     200     15    92%
src/poetry/repositories/installed_repository.py                142      6    96%
src/poetry/repositories/legacy_repository.py                    51      4    92%
src/poetry/repositories/link_sources/base.py                    77      1    99%
src/poetry/repositories/link_sources/html.py                    40      1    98%
src/poetry/repositories/parsers/pypi_search_parser.py           46      1    98%
src/poetry/repositories/pypi_repository.py                     112      9    92%
src/poetry/repositories/repository.py                           65     10    85%
src/poetry/repositories/single_page_repository.py               11      4    64%
src/poetry/toml/file.py                                         26      1    96%
src/poetry/utils/_compat.py                                     27      5    81%
src/poetry/utils/authenticator.py                              256     14    95%
src/poetry/utils/cache.py                                      164      3    98%
src/poetry/utils/dependency_specification.py                   137     18    87%
src/poetry/utils/env/__init__.py                                51      6    88%
src/poetry/utils/env/base_env.py                               248     32    87%
src/poetry/utils/env/env_manager.py                            414     39    91%
src/poetry/utils/env/generic_env.py                             57     13    77%
src/poetry/utils/env/mock_env.py                                45      5    89%
src/poetry/utils/env/null_env.py                                33      1    97%
src/poetry/utils/env/site_packages.py                          117     28    76%
src/poetry/utils/env/system_env.py                              48      6    88%
src/poetry/utils/env/virtual_env.py                             86     13    85%
src/poetry/utils/helpers.py                                    191     54    72%
src/poetry/utils/password_manager.py                           147     11    93%
src/poetry/utils/pip.py                                         22      3    86%
src/poetry/utils/setup_reader.py                               232     20    91%
src/poetry/utils/shell.py                                      106     73    31%
src/poetry/utils/wheel.py                                       26      1    96%
src/poetry/vcs/git/backend.py                                  254    170    33%
src/poetry/version/version_selector.py                          19      1    95%
--------------------------------------------------------------------------------
TOTAL                                                        11063   1144    90%

Posting as a guideline for those who would like to help with test coverage and cleanup