DOC: update developer guide on Handling Dependencies

doc/source/developing/testing.rst

@@ -441,54 +441,47 @@ Handling yt Dependencies
 ------------------------
 
 Our dependencies are specified in ``pyproject.toml``. Hard dependencies are found in
-``options.install_requires``, while optional dependencies are specified in
-``options.extras_require``. The ``full`` target contains the specs to run our
+``project.dependencies``, while optional dependencies are specified in
+``project.optional-dependencies``. The ``full`` target contains the specs to run our
 test suite, which are intended to be as modern as possible (we don't set upper
-limits to versions unless we need to). The ``minimal`` target is used to check
-that we don't break backward compatibility with old versions of upstream
-projects by accident. It is intended to pin strictly our minimal supported
-versions. The ``test`` target specifies the tools needed to run the tests, but
+limits to versions unless we need to).
+
+The ``test`` target specifies the tools needed to run the tests, but
 not needed by yt itself.
 
+Documentation and typechecking requirements are found in ``requirements/``,
+and used in ``tests/ci_install.sh``.
+
 **Python version support.**
-When a new Python version is released, it takes about
-a month or two for yt to support it, since we're dependent on bigger projects
-like numpy and matplotlib. We vow to follow numpy's deprecation plan regarding
-our supported versions for Python and numpy, defined formally in `NEP 29
-<https://numpy.org/neps/nep-0029-deprecation_policy.html>`_. However, we try to
-avoid bumping our minimal requirements shortly before a yt release.
+We vow to follow numpy's deprecation plan regarding our supported versions for Python
+and numpy, defined formally in
+`NEP 29 <https://numpy.org/neps/nep-0029-deprecation_policy.html>`_, but generally
+support larger version intervals than recommended in this document.
 
 **Third party dependencies.**
+We attempt to make yt compatible with a wide variety of upstream software
+versions.
 However, sometimes a specific version of a project that yt depends on
 causes some breakage and must be blacklisted in the tests or a more
 experimental project that yt depends on optionally might change sufficiently
 that the yt community decides not to support an old version of that project.
 
 **Note.**
 Some of our optional dependencies are not trivial to install and their support
-may vary across platforms. To manage such issue, we currently use requirement
-files in additions to ``pyproject.toml``. They are found in
-``tests/*requirements.txt`` and used in ``tests/ci_install.sh``.
-
-We attempt to make yt compatible with a wide variety of upstream software
-versions. However, sometimes a specific version of a project that yt depends on
-causes some breakage and must be blacklisted in the tests or a more
-experimental project that yt depends on optionally might change sufficiently
-that the yt community decides not to support an old version of that project.
-
-To handle cases like this, the versions of upstream software projects installed
-on the machines running the yt test suite are pinned to specific version
-numbers that must be updated manually. This prevents breaking the yt tests when
-a new version of an upstream dependency is released and allows us to manage
-updates in upstream projects at our pace.
+may vary across platforms.
 
 If you would like to add a new dependency for yt (even an optional dependency)
 or would like to update a version of a yt dependency, you must edit the
-``tests/test_requirements.txt`` file, this path is relative to the root of the
-repository. This file contains an enumerated list of direct dependencies and
-pinned version numbers. For new dependencies, simply append the name of the new
+``pyproject.toml`` file. For new dependencies, simply append the name of the new
 dependency to the end of the file, along with a pin to the latest version
 number of the package. To update a package's version, simply update the version
 number in the entry for that package.
 
-Finally, we also run a set of tests with "minimal" dependencies installed. When adding tests that depend on an optional dependency, you can wrap the test with the ``yt.testing.requires_module decorator`` to ensure it does not run during the minimal dependency tests (see yt/frontends/amrvac/tests/test_read_amrvac_namelist.py for a good example). If for some reason you need to update the listing of packages that are installed for the "minimal" dependency tests, you will need to edit ``tests/test_minimal_requirements.txt``.
+Finally, we also run a set of tests with "minimal" dependencies installed.
+When adding tests that depend on an optional dependency, you can wrap the test
+with the ``yt.testing.requires_module decorator`` to ensure it does not run
+during the minimal dependency tests (see
+``yt/frontends/amrvac/tests/test_read_amrvac_namelist.py`` for a good example).
+If for some reason you need to update the listing of packages that are installed
+for the "minimal" dependency tests, you will need to update
+``requirements/minimal_env.txt``.