From 5e3cde40bdff429c0855a905412ac0797246ba40 Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Sat, 8 Oct 2022 06:07:34 -0500
Subject: [PATCH 1/4] prep for jupyter releaser

---
 .github/workflows/check-release.yml |  22 ++
 .github/workflows/enforce-label.yml |  13 +
 .github/workflows/tests.yml         |   7 +
 CHANGELOG.md                        | 503 ++++++++++++++++++++++++++++
 docs/requirements.txt               |   3 +-
 docs/source/changelog.rst           | 489 ---------------------------
 docs/source/conf.py                 |  27 +-
 7 files changed, 562 insertions(+), 502 deletions(-)
 create mode 100644 .github/workflows/check-release.yml
 create mode 100644 .github/workflows/enforce-label.yml
 create mode 100644 CHANGELOG.md
 delete mode 100644 docs/source/changelog.rst

diff --git a/.github/workflows/check-release.yml b/.github/workflows/check-release.yml
new file mode 100644
index 00000000..3e021565
--- /dev/null
+++ b/.github/workflows/check-release.yml
@@ -0,0 +1,22 @@
+name: Check Release
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["*"]
+
+jobs:
+  check_release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Base Setup
+        uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+      - name: Install Dependencies
+        run: |
+          pip install -e .
+      - name: Check Release
+        uses: jupyter-server/jupyter_releaser/.github/actions/check-release@v2
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/enforce-label.yml b/.github/workflows/enforce-label.yml
new file mode 100644
index 00000000..725feab5
--- /dev/null
+++ b/.github/workflows/enforce-label.yml
@@ -0,0 +1,13 @@
+name: Enforce PR label
+
+on:
+  pull_request:
+    types: [labeled, unlabeled, opened, edited, synchronize]
+jobs:
+  enforce-label:
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    steps:
+      - name: enforce-triage-label
+        uses: jupyterlab/maintainer-tools/.github/actions/enforce-label@v1
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index bfe483d2..b181e7ed 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -100,6 +100,13 @@ jobs:
       - uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
       - uses: jupyterlab/maintainer-tools/.github/actions/test-sdist@v1
 
+  check_links:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+      - uses: jupyterlab/maintainer-tools/.github/actions/check-links@v1
+
   pre-commit:
     name: pre-commit
     runs-on: ubuntu-latest
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 00000000..28d1872b
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,503 @@
+# Changes in Traitlets
+
+<!-- <START NEW CHANGELOG ENTRY> -->
+
+## 5.4.0
+
+- Fix version_info
+- Make generated config files more lintable
+- Fix union trait from string
+- Add security.md, and tidelift bage
+
+<!-- <END NEW CHANGELOG ENTRY> -->
+
+## 5.3.0
+
+- Fix traitlet name in docstring
+- Re-support multiple-alias key for ArgParseConfigLoader
+
+## 5.2.2
+
+- Make `traitlets.__all__` explicit and validate in test.
+- Fix `KeyError` in `Application.get_default_logging_config`.
+
+## 5.2.1
+
+- logging: Don't attempt to close handlers unless they have been
+  opened. Fixes `ValueError: Unable to configure formatter 'console'` traceback.
+
+## 5.2.0
+
+Traitlets 5.2 brings a couple of updates and changes to traitlets, and
+is recommended for all users. What follows is a non-exhaustive list of
+changes:
+
+- Application: add logging_config trait.
+- Disambiguate the use of the term value in the example.
+- Add mypy typing support.
+- DOC: Add log example.
+- Internal cleanup: linters, autoformatters, CI.
+
+## 5.1.1
+
+5.1.1 fixes compatibility issues with Python 3.10 (rc2).
+
+## 5.1.0
+
+Traitlets 5.1 brings a couple of updates and changes to traitlets, and
+is recommended for all users. What follow is a non-exhaustive list of
+changes:
+
+- Removal of the `ipython_genutils` dependency, this should remove
+  any direct and indirect reliance on `nose` and prepare traitlets
+  5.1 for Python 3.10 and above compatibility, some test suite
+  changes also accommodate Python 3.10 changes. If you package
+  traitlets downstream, make sure to remove this dependency.
+- Removal of `ipython_genutils` may have change the default encoding
+  detected for the command line argument parsing when not utf-8. We
+  expect this to affect a small portion of older windows version. If
+  you encounter issue let us know.
+- Stop recommendation of `CUnicode` in some circumstances as it's
+  deprecated.
+- Our test suite is now using GitHub action instead of travis CI. If
+  you are packaging downstream using the git repository, you may
+  have to exclude the `.github` folder now, and can remove exclusion
+  of
+- It fixes a parsing issue for list of one single element on the
+  CLI.
+- We reserve the right to remove official support for Python 3.7 in
+  subsequent minor revisions.
+
+## 5.0.5
+
+- Support deprecated literals for sets, tuples on the command-line:
+  `nbconvert --TagRemovePreprocessor.remove_cell_tags='{"tag"}'`
+- Fix `from_string_list` for Tuples in general
+- Fix support for `List(default_value=None, allow_none=True)` and
+  other Container traits
+- Fix help output for nested aliases and tuple traits
+
+## 5.0.4
+
+- Support deprecated use of byte-literals for bytes on the
+  command-line: `ipython kernel --Session.key="b'abc'"`. The
+  `b` prefix is no longer needed in traitlets 5.0, but is
+  supported for backward-compatibility
+- Improve output of configuration errors, especially when help output
+  would make it hard to find the helpful error message
+
+## 5.0.3
+
+- Fix regression in handling `--opt=None` on the CLI for
+  configurable traits with `allow_none=True`
+
+## 5.0.2
+
+- Fix casting bytes to unicode
+
+## 5.0.0
+
+(This is an in-progress changelog, please let us know if something is
+missing/or could be phrased better)
+
+Traitlets 5.0 is a new version of traitlets that accumulate changes over
+a period of more close to four years; A number of internal refactoring
+made the internal code structure cleaner and simpler, and greatly
+improved the diagnostic error messages as well has help and
+documentation generation.
+
+We expect no code change needed for any consumer of the Python API
+(ipywidgets, and alike), though CLI argument parsing have seen a
+complete rewrite, so if you have an application that does use the
+parsing logic of traitlets you may see changes in behavior, and now have
+access to more features. There was also a cleanup of what was considered
+a part of the public API, certain previously exposed utility functions
+and types are no longer available. Please see an exhausive list below.
+
+::: seealso
+`commandline` docs for details about
+command-line parsing and the changes in 5.0.
+
+Please [let us know](https://github.com/ipython/traitlets/issues) if you
+find issues with the new command-line parsing changes.
+:::
+
+We also want to thanks in particular a number of regular contributor
+through the years that have patiently waited for their often large
+contribution to be available, if **rough** order of number of
+contribution:
+
+- Ryan Morshead - \@rmorshea - For serving as a maintainer of the
+  4.x branch and providing a number of bug fix through the years.
+- Kostis Anagnostopoulos - \@ankostis - Who push a major refactor of
+  the CLI paring, as well as many help-generating function.
+- Benjamin Ragan-Kelley -- \@minrk -- for reviewing and help fixing
+  edge case in most of the above
+- Matthias Bussonnier -- \@carreau
+- Sylvain Corlay
+- Francisco de la Peña
+- Martin Renou
+- Yves Delley
+- Thomas Kluyver
+- hristian Clauss
+- maartenbreddels
+- Aliaksei Urbanski
+- Kevin Bates
+- David Brochart
+
+As well as many of the passer-by, and less frequent contributors:
+
+- Tim Paine
+- Jake VanderPlas
+- Frédéric Chapoton
+- Dan Allan
+- Adam Chainz
+- William Krinsman
+- Travis DePrato
+- Todd
+- Thomas Aarholt
+- Lumir Balhar
+- Leonardo Uieda
+- Leo Gallucci
+- Kyle Kelley
+- Jeroen Demeyer
+- Jason Grout
+- Hans Moritz Günther
+- FredInChina
+- Conner Cowling
+- Carol Willing
+- Albert Zeyer
+
+Major changes are:
+
+- Removal of Python 2 support,
+- Removal of Python 3.0-3.6 support
+- we now follow NEP 29, and are thus Python 3.7+ only.
+- remove `six` as a dependency
+- remove `funcsig` as a dependency.
+- no longer exposes the following functions / types:
+  - ClassTypes
+  - DefaultHandler
+  - EventHandler
+  - ForwardDeclaredMixin
+  - ObserveHandler
+  - SequenceTypes
+  - ValidateHandler
+  - add_article
+  - class_of
+  - getargspec
+  - getmembers
+  - is_trait
+  - isidentifier
+  - repr_type
+
+Here is a list of most Pull requests that went into 5.0 and a short
+description.
+
+- [#362](https://github.com/ipython/traitlets/pull/362) , [#361](https://github.com/ipython/traitlets/pull/361) introduces:
+  - help for aliases , aliases dict values can now be a tuple with
+    ('target', 'help string')
+  - subcommands can now be arbitrary callable and do not need to be
+    subclass of `Application`
+- [#306](https://github.com/ipython/traitlets/pull/306) Add compatibility with the
+  `trait` package for Dictionaries and add the `key_trait` parameters
+  allowing to restrict the type of the key of a mapping. The
+  constructor parameters `trait` and `traits` are renamed to
+  `value_trait` and `per_key_traits`.
+- [#319](https://github.com/ipython/traitlets/pull/319) adds ability to introduce
+  both shot and long version of aliases, allowing for short and long
+  options `-` and `--`.
+- [#322](https://github.com/ipython/traitlets/pull/322) rewrite command line argument
+  parsing to use argparse, and allow more flexibility in assigning
+  literals without quoting.
+- [#332](https://github.com/ipython/traitlets/pull/332) Make it easier to redefined
+  default values of parents classes.
+- [#333](https://github.com/ipython/traitlets/pull/333) introduces a
+  `Callable` trait.
+- [#340](https://github.com/ipython/traitlets/pull/340) Old way of passing containers
+  in the command line is now deprecated, and will emit warning on the
+  command line.
+- [#341](https://github.com/ipython/traitlets/pull/341) introduces
+  `--Application.show_config=True` which will make by default any
+  application show it configuration, all the files it loaded
+  configuration from, and exit.
+- [#349](https://github.com/ipython/traitlets/pull/349) unify ability to declare
+  default values across traitlets with a singular method `default`
+  method, and [#525](https://github.com/ipython/traitlets/pull/525) adds a warning
+  that `Undefined`is deprecated.
+- [#355](https://github.com/ipython/traitlets/pull/355) fix a random ordering issues
+  in command lines flags.
+- [#356](https://github.com/ipython/traitlets/pull/356) allow both `self` and `cls`
+  in `__new__` method for genericity.
+- [#360](https://github.com/ipython/traitlets/pull/360) Simplify overwriting and
+  extending the command line argument parser.
+- [#371](https://github.com/ipython/traitlets/pull/371) introduces a
+  `FuzzyEnum` trait that allow case
+  insensitive and unique prefix matching.
+- [#384](https://github.com/ipython/traitlets/pull/384) Ass a
+  `trait_values` method to extra a mapping of trait and
+  their values.
+- [#393](https://github.com/ipython/traitlets/pull/393) `Link` now have a
+  transform attribute (taking two functions inverse of each other),
+  that affect how a value is mapped between a source and a target.
+- [#394](https://github.com/ipython/traitlets/pull/394) `Link` now have a
+  `link` method to re-link object after
+  `unlink` has been called.
+- [#402](https://github.com/ipython/traitlets/pull/402) rewrite handling of error
+  messages for nested traits.
+- [#405](https://github.com/ipython/traitlets/pull/405) all function that use to
+  print help now have an equivalent that yields the help lines.
+- [#413](https://github.com/ipython/traitlets/pull/413) traits now have a method
+  `trait_has_value`, returning a boolean to know if a
+  value has been assigned to a trait (excluding the default), in order
+  to help avoiding circular validation at initialisation.
+- [#416](https://github.com/ipython/traitlets/pull/416) Explicitly export traitlets
+  in `__all__` to avoid exposing implementation details.
+- [#438](https://github.com/ipython/traitlets/pull/438) introduces `.info_rst()` to
+  let traitlets overwrite the automatically generated rst
+  documentation.
+- [#458](https://github.com/ipython/traitlets/pull/458) Add a sphinx extension to
+  automatically document options of `Application` instance
+  in projects using traitlets.
+- [#509](https://github.com/ipython/traitlets/pull/509) remove all base `except:`
+  meaning traitlets will not catch a number of
+  `BaseException` s anymore.
+- [#515](https://github.com/ipython/traitlets/pull/515) Add a class decorator to
+  enable tab completion of keyword arguments in signature.
+- [#516](https://github.com/ipython/traitlets/pull/516) a `Sentinel` Traitlets was
+  made public by mistake and is now deprecated.
+- [#517](https://github.com/ipython/traitlets/pull/517) use parent Logger within
+  logggin configurable when possible.
+- [#522](https://github.com/ipython/traitlets/pull/522) Make loading config files
+  idempotent and expose the list of loaded config files for long
+  running services.
+
+### API changes
+
+This list is auto-generated by `frappuccino`, comparing with traitlets
+4.3.3 API and editied for shortness:
+
+    The following items are new:
+        + traitlets.Sentinel
+        + traitlets.config.application.Application.emit_alias_help(self)
+        + traitlets.config.application.Application.emit_description(self)
+        + traitlets.config.application.Application.emit_examples(self)
+        + traitlets.config.application.Application.emit_flag_help(self)
+        + traitlets.config.application.Application.emit_help(self, classes=False)
+        + traitlets.config.application.Application.emit_help_epilogue(self, classes)
+        + traitlets.config.application.Application.emit_options_help(self)
+        + traitlets.config.application.Application.emit_subcommands_help(self)
+        + traitlets.config.application.Application.start_show_config(self)
+        + traitlets.config.application.default_aliases
+        + traitlets.config.application.default_flags
+        + traitlets.config.default_aliases
+        + traitlets.config.default_flags
+        + traitlets.config.loader.DeferredConfig
+        + traitlets.config.loader.DeferredConfig.get_value(self, trait)
+        + traitlets.config.loader.DeferredConfigList
+        + traitlets.config.loader.DeferredConfigList.get_value(self, trait)
+        + traitlets.config.loader.DeferredConfigString
+        + traitlets.config.loader.DeferredConfigString.get_value(self, trait)
+        + traitlets.config.loader.LazyConfigValue.merge_into(self, other)
+        + traitlets.config.loader.Undefined
+        + traitlets.config.loader.class_trait_opt_pattern
+        + traitlets.traitlets.BaseDescriptor.subclass_init(self, cls)
+        + traitlets.traitlets.Bool.from_string(self, s)
+        + traitlets.traitlets.Bytes.from_string(self, s)
+        + traitlets.traitlets.Callable
+        + traitlets.traitlets.Callable.validate(self, obj, value)
+        + traitlets.traitlets.CaselessStrEnum.info(self)
+        + traitlets.traitlets.CaselessStrEnum.info_rst(self)
+        + traitlets.traitlets.Complex.from_string(self, s)
+        + traitlets.traitlets.Container.from_string(self, s)
+        + traitlets.traitlets.Container.from_string_list(self, s_list)
+        + traitlets.traitlets.Container.item_from_string(self, s)
+        + traitlets.traitlets.Dict.from_string(self, s)
+        + traitlets.traitlets.Dict.from_string_list(self, s_list)
+        + traitlets.traitlets.Dict.item_from_string(self, s)
+        + traitlets.traitlets.Enum.from_string(self, s)
+        + traitlets.traitlets.Enum.info_rst(self)
+        + traitlets.traitlets.Float.from_string(self, s)
+        + traitlets.traitlets.FuzzyEnum
+        + traitlets.traitlets.FuzzyEnum.info(self)
+        + traitlets.traitlets.FuzzyEnum.info_rst(self)
+        + traitlets.traitlets.FuzzyEnum.validate(self, obj, value)
+        + traitlets.traitlets.HasTraits.trait_defaults(self, *names, **metadata)
+        + traitlets.traitlets.HasTraits.trait_has_value(self, name)
+        + traitlets.traitlets.HasTraits.trait_values(self, **metadata)
+        + traitlets.traitlets.Instance.from_string(self, s)
+        + traitlets.traitlets.Int.from_string(self, s)
+        + traitlets.traitlets.ObjectName.from_string(self, s)
+        + traitlets.traitlets.TCPAddress.from_string(self, s)
+        + traitlets.traitlets.TraitType.default(self, obj='None')
+        + traitlets.traitlets.TraitType.from_string(self, s)
+        + traitlets.traitlets.Unicode.from_string(self, s)
+        + traitlets.traitlets.Union.default(self, obj='None')
+        + traitlets.traitlets.UseEnum.info_rst(self)
+        + traitlets.traitlets.directional_link.link(self)
+        + traitlets.traitlets.link.link(self)
+        + traitlets.utils.cast_unicode(s, encoding='None')
+        + traitlets.utils.decorators
+        + traitlets.utils.decorators.Undefined
+        + traitlets.utils.decorators.signature_has_traits(cls)
+        + traitlets.utils.descriptions
+        + traitlets.utils.descriptions.add_article(name, definite=False, capital=False)
+        + traitlets.utils.descriptions.class_of(value)
+        + traitlets.utils.descriptions.describe(article, value, name='None', verbose=False, capital=False)
+        + traitlets.utils.descriptions.repr_type(obj)
+
+    The following items have been removed (or moved to superclass):
+        - traitlets.ClassTypes
+        - traitlets.SequenceTypes
+        - traitlets.config.absolute_import
+        - traitlets.config.application.print_function
+        - traitlets.config.configurable.absolute_import
+        - traitlets.config.configurable.print_function
+        - traitlets.config.loader.KeyValueConfigLoader.clear
+        - traitlets.config.loader.KeyValueConfigLoader.load_config
+        - traitlets.config.loader.flag_pattern
+        - traitlets.config.loader.kv_pattern
+        - traitlets.config.print_function
+        - traitlets.traitlets.ClassBasedTraitType.error
+        - traitlets.traitlets.Container.element_error
+        - traitlets.traitlets.List.validate
+        - traitlets.traitlets.TraitType.instance_init
+        - traitlets.traitlets.Union.make_dynamic_default
+        - traitlets.traitlets.add_article
+        - traitlets.traitlets.class_of
+        - traitlets.traitlets.repr_type
+        - traitlets.utils.getargspec.PY3
+        - traitlets.utils.importstring.string_types
+        - traitlets.warn_explicit
+
+    The following signatures differ between versions:
+
+        - traitlets.config.application.Application.generate_config_file(self)
+        + traitlets.config.application.Application.generate_config_file(self, classes='None')
+
+        - traitlets.config.application.catch_config_error(method, app, *args, **kwargs)
+        + traitlets.config.application.catch_config_error(method)
+
+        - traitlets.config.configurable.Configurable.class_config_section()
+        + traitlets.config.configurable.Configurable.class_config_section(classes='None')
+
+        - traitlets.config.configurable.Configurable.class_get_trait_help(trait, inst='None')
+        + traitlets.config.configurable.Configurable.class_get_trait_help(trait, inst='None', helptext='None')
+
+        - traitlets.config.loader.ArgParseConfigLoader.load_config(self, argv='None', aliases='None', flags='None')
+        + traitlets.config.loader.ArgParseConfigLoader.load_config(self, argv='None', aliases='None', flags='<deprecated>', classes='None')
+
+        - traitlets.traitlets.Dict.element_error(self, obj, element, validator)
+        + traitlets.traitlets.Dict.element_error(self, obj, element, validator, side='Values')
+
+        - traitlets.traitlets.HasDescriptors.setup_instance(self, *args, **kwargs)
+        + traitlets.traitlets.HasDescriptors.setup_instance(*args, **kwargs)
+
+        - traitlets.traitlets.HasTraits.setup_instance(self, *args, **kwargs)
+        + traitlets.traitlets.HasTraits.setup_instance(*args, **kwargs)
+
+        - traitlets.traitlets.TraitType.error(self, obj, value)
+        + traitlets.traitlets.TraitType.error(self, obj, value, error='None', info='None')
+
+## 4.3
+
+## 4.3.2
+
+[4.3.2 on GitHub](https://github.com/ipython/traitlets/milestones/4.3.2)
+
+4.3.2 is a tiny release, relaxing some of the deprecations introduced in
+4.3.1:
+
+- using `_traitname_default()` without
+  the `@default` decorator is no longer deprecated.
+- Passing `config=True` in traitlets constructors is no longer
+  deprecated.
+
+## 4.3.1
+
+[4.3.1 on GitHub](https://github.com/ipython/traitlets/milestones/4.3.1)
+
+- Compatibility fix for Python 3.6a1
+- Fix bug in Application.classes getting extra entries when multiple
+  Applications are instantiated in the same process.
+
+## 4.3.0
+
+[4.3.0 on GitHub](https://github.com/ipython/traitlets/milestones/4.3)
+
+- Improve the generated config file output.
+- Allow TRAITLETS_APPLICATION_RAISE_CONFIG_FILE_ERROR env to override
+  `Application.raise_config_file_errors`, so that config file errors can
+  result in exiting immediately.
+- Avoid using root logger. If no application logger is registered, the
+  `'traitlets'` logger will be used instead of the root logger.
+- Change/Validation arguments are now Bunch objects, allowing
+  attribute-access, in addition to dictionary access.
+- Reduce number of common deprecation messages in certain cases.
+- Ensure command-line options always have higher priority than config
+  files.
+- Add bounds on numeric traits.
+- Improves various error messages.
+
+## 4.2
+
+## 4.2.2 - 2016-07-01
+
+[4.2.2 on GitHub](https://github.com/ipython/traitlets/milestones/4.2.2)
+
+Partially revert a change in 4.1 that prevented IPython's command-line
+options from taking priority over config files.
+
+## 4.2.1 - 2016-03-14
+
+[4.2.1 on GitHub](https://github.com/ipython/traitlets/milestones/4.2.1)
+
+Demotes warning about unused arguments in `HasTraits.__init__`
+introduced in 4.2.0 to DeprecationWarning.
+
+## 4.2.0 - 2016-03-14
+
+[4.2 on GitHub](https://github.com/ipython/traitlets/milestones/4.2)
+
+- `JSONFileConfigLoader` can be used
+  as a context manager for updating configuration.
+- If a value in config does not map onto a configurable trait, a
+  message is displayed that the value will have no effect.
+- Unused arguments are passed to `super()` in `HasTraits.__init__`,
+  improving support for multiple inheritance.
+- Various bugfixes and improvements in the new API introduced in 4.1.
+- Application subclasses may specify `raise_config_file_errors = True`
+  to exit on failure to load config files, instead of the default of
+  logging the failures.
+
+## 4.1 - 2016-01-15
+
+[4.1 on GitHub](https://github.com/ipython/traitlets/milestones/4.1)
+
+Traitlets 4.1 introduces a totally new decorator-based API for
+configuring traitlets. Highlights:
+
+- Decorators are used, rather than magic method names, for registering
+  trait-related methods. See `using_traitlets` and `migration` for more
+  info.
+- Deprecate `Trait(config=True)` in favor of
+  `Trait().tag(config=True)`. In general, metadata is added via `tag`
+  instead of the constructor.
+
+Other changes:
+
+- Trait attributes initialized with `read_only=True` can only be set
+  with the `set_trait` method. Attempts to directly modify a read-only
+  trait attribute raises a `TraitError`.
+- The directional link now takes an optional `transform`
+  attribute allowing the modification of the value.
+- Various fixes and improvements to config-file generation (fixed
+  ordering, Undefined showing up, etc.)
+- Warn on unrecognized traits that aren't configurable, to avoid
+  silently ignoring mistyped config.
+
+## 4.0 - 2015-06-19
+
+[4.0 on GitHub](https://github.com/ipython/traitlets/milestones/4.0)
+
+First release of traitlets as a standalone package.
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 7089a5a7..f9d5d75b 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,4 @@
 -e ../.
+myst-parser
+pydata-sphinx-theme
 Sphinx
-sphinx_rtd_theme
diff --git a/docs/source/changelog.rst b/docs/source/changelog.rst
deleted file mode 100644
index fc7994b9..00000000
--- a/docs/source/changelog.rst
+++ /dev/null
@@ -1,489 +0,0 @@
-Changes in Traitlets
-====================
-
-Traitlets 5.4
--------------
-
-5.4.0
-*****
-
-  - Fix version_info
-  - Make generated config files more lintable
-  - Fix union trait from string
-  - Add security.md, and tidelift bage
-
-Traitlets 5.3
--------------
-
-5.3.0
-*****
-
-  - Fix traitlet name in docstring
-  - Re-support multiple-alias key for ArgParseConfigLoader
-
-Traitlets 5.2
--------------
-
-5.2.2
-*****
-
-   - Make ``traitlets.__all__`` explicit and validate in test.
-   - Fix ``KeyError`` in ``Application.get_default_logging_config``.
-
-5.2.1
-*****
-
-  - logging: Don't attempt to close handlers unless they have been opened.
-    Fixes ``ValueError: Unable to configure formatter 'console'`` traceback.
-
-5.2.0
-*****
-
-Traitlets 5.2 brings a couple of updates and changes to traitlets, and is
-recommended for all users. What follows is a non-exhaustive list of changes:
-
-  - Application: add logging_config trait.
-  - Disambiguate the use of the term value in the example.
-  - Add mypy typing support.
-  - DOC: Add log example.
-  - Internal cleanup: linters, autoformatters, CI.
-
-Traitlets 5.1
--------------
-
-5.1.1
-*****
-
-5.1.1 fixes compatibility issues with Python 3.10 (rc2).
-
-5.1.0
-*****
-
-Traitlets 5.1 brings a couple of updates and changes to traitlets, and is
-recommended for all users. What follow is a non-exhaustive list of changes:
-
- - Removal of the ``ipython_genutils`` dependency, this should remove any direct
-   and indirect reliance on ``nose`` and prepare traitlets 5.1 for Python 3.10
-   and above compatibility, some test suite changes also accommodate Python 3.10 changes.
-   If you package traitlets downstream, make sure to remove this dependency.
-
- - Removal of ``ipython_genutils`` may have change the default encoding detected
-   for the command line argument parsing when not utf-8. We expect this to
-   affect a small portion of older windows version. If you encounter issue let
-   us know.
-
- - Stop recommendation of ``CUnicode`` in some circumstances as it's
-   deprecated.
-
- - Our test suite is now using GitHub action instead of travis CI. If you are
-   packaging downstream using the git repository, you may have to exclude the
-   ``.github`` folder now, and can remove exclusion of
-
- - It fixes a parsing issue for list of one single element on the CLI.
-
- - We reserve the right to remove official support for Python 3.7 in subsequent
-   minor revisions.
-
-
-Traitlets 5.0
--------------
-
-5.0.5
-*****
-
-- Support deprecated literals for sets, tuples on the command-line: ``nbconvert --TagRemovePreprocessor.remove_cell_tags='{"tag"}'``
-- Fix ``from_string_list`` for Tuples in general
-- Fix support for ``List(default_value=None, allow_none=True)`` and other Container traits
-- Fix help output for nested aliases and tuple traits
-
-5.0.4
-*****
-
-- Support deprecated use of byte-literals for bytes on the command-line:
-  ``ipython kernel --Session.key="b'abc'"``. The `b` prefix is no longer needed
-  in traitlets 5.0, but is supported for backward-compatibility
-- Improve output of configuration errors, especially when help output would make it hard to find the helpful error message
-
-5.0.3
-*****
-
-- Fix regression in handling `--opt=None` on the CLI for configurable traits
-  with `allow_none=True`
-
-5.0.2
-*****
-
-- Fix casting bytes to unicode
-
-5.0.0
-*****
-
-
-(This is an in-progress changelog, please let us know if something is missing/or could be phrased better)
-
-Traitlets 5.0 is a new version of traitlets that accumulate changes over a period of more close to four years; A number of
-internal refactoring made the internal code structure cleaner and simpler, and greatly improved the diagnostic error
-messages as well has help and documentation generation.
-
-We expect no code change needed for any consumer of the Python API (ipywidgets, and alike),
-though CLI argument parsing have seen a complete rewrite,
-so if you have an application that does use the parsing logic of traitlets you may see changes in behavior,
-and now have access to more features. There was also a cleanup of what was considered a part of the public API,
-certain previously exposed utility functions and types are no longer available. Please see an exhausive list below.
-
-.. seealso::
-
-  :ref:`commandline` for details about command-line parsing and the changes in 5.0.
-
-  Please `let us know <https://github.com/ipython/traitlets/issues>`__
-  if you find issues with the new command-line parsing changes.
-
-We also want to thanks in particular a number of regular contributor through the years that have patiently waited for
-their often large contribution to be available, if **rough** order of number of contribution:
-
-  - Ryan Morshead - @rmorshea - For serving as a maintainer of the 4.x branch and providing a number of bug fix through
-    the years.
-  - Kostis Anagnostopoulos - @ankostis - Who push a major refactor of the CLI paring, as well as many help-generating
-    function.
-  - Benjamin Ragan-Kelley – @minrk – for reviewing and help fixing edge case in most of the above
-  - Matthias Bussonnier – @carreau
-  - Sylvain Corlay
-  - Francisco de la Peña
-  - Martin Renou
-  - Yves Delley
-  - Thomas Kluyver
-  - hristian Clauss
-  - maartenbreddels
-  - Aliaksei Urbanski
-  - Kevin Bates
-  - David Brochart
-
-As well as many of the passer-by, and less frequent contributors:
-
-  - Tim Paine
-  - Jake VanderPlas
-  - Frédéric Chapoton
-  - Dan Allan
-  - Adam Chainz
-  - William Krinsman
-  - Travis DePrato
-  - Todd
-  - Thomas Aarholt
-  - Lumir Balhar
-  - Leonardo Uieda
-  - Leo Gallucci
-  - Kyle Kelley
-  - Jeroen Demeyer
-  - Jason Grout
-  - Hans Moritz Günther
-  - FredInChina
-  - Conner Cowling
-  - Carol Willing
-  - Albert Zeyer
-
-
-Major changes are:
-
- - Removal of Python 2 support,
- - Removal of Python 3.0-3.6 support
- - we now follow NEP 29, and are thus Python 3.7+ only.
- - remove ``six`` as a dependency
- - remove ``funcsig`` as a dependency.
- - no longer exposes the following functions / types:
-
-   - ClassTypes
-   - DefaultHandler
-   - EventHandler
-   - ForwardDeclaredMixin
-   - ObserveHandler
-   - SequenceTypes
-   - ValidateHandler
-   - add_article
-   - class_of
-   - getargspec
-   - getmembers
-   - is_trait
-   - isidentifier
-   - repr_type
-
-
-
-Here is a list of most Pull requests that went into 5.0 and a short description.
-
-- :ghpull:`362` , :ghpull:`361` introduces:
-  - help for aliases , aliases dict values can now be a tuple with ('target', 'help string')
-  - subcommands can now be arbitrary callable and do not need to be subclass of :any:`Application`
-- :ghpull:`306` Add compatibility with the ``trait`` package for Dictionaries and add the ``key_trait`` parameters
-  allowing to restrict the type of the key of a mapping. The constructor parameters ``trait`` and ``traits`` are renamed
-  to ``value_trait`` and ``per_key_traits``.
-- :ghpull:`319` adds ability to introduce both shot and long version of aliases, allowing for short and long options ``-`` and ``--``.
-- :ghpull:`322` rewrite command line argument parsing to use argparse, and allow more flexibility in assigning literals without quoting.
-- :ghpull:`332` Make it easier to redefined default values of parents classes.
-- :ghpull:`333` introduces a :any:`Callable` trait.
-- :ghpull:`340` Old way of passing containers in the command line is now deprecated, and will emit warning on the command line.
-- :ghpull:`341` introduces ``--Application.show_config=True``  which will make by default any application show it configuration, all the files it loaded configuration from, and exit.
-- :ghpull:`349` unify ability to declare default values across traitlets with a singular method ``default`` method, and :ghpull:`525` adds a warning that `Undefined` is deprecated.
-- :ghpull:`355` fix a random ordering issues in command lines flags.
-- :ghpull:`356` allow both ``self`` and ``cls`` in ``__new__`` method for genericity.
-- :ghpull:`360` Simplify overwriting and extending the command line argument parser.
-- :ghpull:`371` introduces a :any:`FuzzyEnum` trait that allow case insensitive and unique prefix matching.
-- :ghpull:`384` Ass a `trait_values` method to extra a mapping of trait and their values.
-- :ghpull:`393` `Link` now have a transform attribute (taking two functions inverse of each other), that affect how a
-  value is mapped between a source and a target.
-- :ghpull:`394` `Link` now have a `link` method to re-link object after `unlink` has been called.
-- :ghpull:`402` rewrite handling of error messages for nested traits.
-- :ghpull:`405` all function that use to print help now have an equivalent that yields the help lines.
-- :ghpull:`413` traits now have a method `trait_has_value`, returning a boolean to know if a value has been assigned to
-  a trait (excluding the default), in order to help avoiding circular validation at initialisation.
-- :ghpull:`416` Explicitly export traitlets  in ``__all__`` to avoid exposing implementation details.
-- :ghpull:`438` introduces ``.info_rst()`` to let traitlets overwrite the automatically generated rst documentation.
-- :ghpull:`458` Add a sphinx extension to automatically document options of `Application` instance in projects using traitlets.
-- :ghpull:`509` remove all base ``except:`` meaning traitlets will not catch a number of :any:`BaseException` s anymore.
-- :ghpull:`515` Add a class decorator to enable tab completion of keyword arguments in signature.
-- :ghpull:`516` a ``Sentinel`` Traitlets was made public by mistake and is now deprecated.
-- :ghpull:`517` use parent Logger within logggin configurable when possible.
-- :ghpull:`522` Make loading config files idempotent and expose the list of loaded config files for long running services.
-
-
-API changes
-***********
-
-This list is auto-generated by ``frappuccino``, comparing with traitlets 4.3.3 API and editied for shortness::
-
-
-
-    The following items are new:
-        + traitlets.Sentinel
-        + traitlets.config.application.Application.emit_alias_help(self)
-        + traitlets.config.application.Application.emit_description(self)
-        + traitlets.config.application.Application.emit_examples(self)
-        + traitlets.config.application.Application.emit_flag_help(self)
-        + traitlets.config.application.Application.emit_help(self, classes=False)
-        + traitlets.config.application.Application.emit_help_epilogue(self, classes)
-        + traitlets.config.application.Application.emit_options_help(self)
-        + traitlets.config.application.Application.emit_subcommands_help(self)
-        + traitlets.config.application.Application.start_show_config(self)
-        + traitlets.config.application.default_aliases
-        + traitlets.config.application.default_flags
-        + traitlets.config.default_aliases
-        + traitlets.config.default_flags
-        + traitlets.config.loader.DeferredConfig
-        + traitlets.config.loader.DeferredConfig.get_value(self, trait)
-        + traitlets.config.loader.DeferredConfigList
-        + traitlets.config.loader.DeferredConfigList.get_value(self, trait)
-        + traitlets.config.loader.DeferredConfigString
-        + traitlets.config.loader.DeferredConfigString.get_value(self, trait)
-        + traitlets.config.loader.LazyConfigValue.merge_into(self, other)
-        + traitlets.config.loader.Undefined
-        + traitlets.config.loader.class_trait_opt_pattern
-        + traitlets.traitlets.BaseDescriptor.subclass_init(self, cls)
-        + traitlets.traitlets.Bool.from_string(self, s)
-        + traitlets.traitlets.Bytes.from_string(self, s)
-        + traitlets.traitlets.Callable
-        + traitlets.traitlets.Callable.validate(self, obj, value)
-        + traitlets.traitlets.CaselessStrEnum.info(self)
-        + traitlets.traitlets.CaselessStrEnum.info_rst(self)
-        + traitlets.traitlets.Complex.from_string(self, s)
-        + traitlets.traitlets.Container.from_string(self, s)
-        + traitlets.traitlets.Container.from_string_list(self, s_list)
-        + traitlets.traitlets.Container.item_from_string(self, s)
-        + traitlets.traitlets.Dict.from_string(self, s)
-        + traitlets.traitlets.Dict.from_string_list(self, s_list)
-        + traitlets.traitlets.Dict.item_from_string(self, s)
-        + traitlets.traitlets.Enum.from_string(self, s)
-        + traitlets.traitlets.Enum.info_rst(self)
-        + traitlets.traitlets.Float.from_string(self, s)
-        + traitlets.traitlets.FuzzyEnum
-        + traitlets.traitlets.FuzzyEnum.info(self)
-        + traitlets.traitlets.FuzzyEnum.info_rst(self)
-        + traitlets.traitlets.FuzzyEnum.validate(self, obj, value)
-        + traitlets.traitlets.HasTraits.trait_defaults(self, *names, **metadata)
-        + traitlets.traitlets.HasTraits.trait_has_value(self, name)
-        + traitlets.traitlets.HasTraits.trait_values(self, **metadata)
-        + traitlets.traitlets.Instance.from_string(self, s)
-        + traitlets.traitlets.Int.from_string(self, s)
-        + traitlets.traitlets.ObjectName.from_string(self, s)
-        + traitlets.traitlets.TCPAddress.from_string(self, s)
-        + traitlets.traitlets.TraitType.default(self, obj='None')
-        + traitlets.traitlets.TraitType.from_string(self, s)
-        + traitlets.traitlets.Unicode.from_string(self, s)
-        + traitlets.traitlets.Union.default(self, obj='None')
-        + traitlets.traitlets.UseEnum.info_rst(self)
-        + traitlets.traitlets.directional_link.link(self)
-        + traitlets.traitlets.link.link(self)
-        + traitlets.utils.cast_unicode(s, encoding='None')
-        + traitlets.utils.decorators
-        + traitlets.utils.decorators.Undefined
-        + traitlets.utils.decorators.signature_has_traits(cls)
-        + traitlets.utils.descriptions
-        + traitlets.utils.descriptions.add_article(name, definite=False, capital=False)
-        + traitlets.utils.descriptions.class_of(value)
-        + traitlets.utils.descriptions.describe(article, value, name='None', verbose=False, capital=False)
-        + traitlets.utils.descriptions.repr_type(obj)
-
-    The following items have been removed (or moved to superclass):
-        - traitlets.ClassTypes
-        - traitlets.SequenceTypes
-        - traitlets.config.absolute_import
-        - traitlets.config.application.print_function
-        - traitlets.config.configurable.absolute_import
-        - traitlets.config.configurable.print_function
-        - traitlets.config.loader.KeyValueConfigLoader.clear
-        - traitlets.config.loader.KeyValueConfigLoader.load_config
-        - traitlets.config.loader.flag_pattern
-        - traitlets.config.loader.kv_pattern
-        - traitlets.config.print_function
-        - traitlets.traitlets.ClassBasedTraitType.error
-        - traitlets.traitlets.Container.element_error
-        - traitlets.traitlets.List.validate
-        - traitlets.traitlets.TraitType.instance_init
-        - traitlets.traitlets.Union.make_dynamic_default
-        - traitlets.traitlets.add_article
-        - traitlets.traitlets.class_of
-        - traitlets.traitlets.repr_type
-        - traitlets.utils.getargspec.PY3
-        - traitlets.utils.importstring.string_types
-        - traitlets.warn_explicit
-
-    The following signatures differ between versions:
-
-        - traitlets.config.application.Application.generate_config_file(self)
-        + traitlets.config.application.Application.generate_config_file(self, classes='None')
-
-        - traitlets.config.application.catch_config_error(method, app, *args, **kwargs)
-        + traitlets.config.application.catch_config_error(method)
-
-        - traitlets.config.configurable.Configurable.class_config_section()
-        + traitlets.config.configurable.Configurable.class_config_section(classes='None')
-
-        - traitlets.config.configurable.Configurable.class_get_trait_help(trait, inst='None')
-        + traitlets.config.configurable.Configurable.class_get_trait_help(trait, inst='None', helptext='None')
-
-        - traitlets.config.loader.ArgParseConfigLoader.load_config(self, argv='None', aliases='None', flags='None')
-        + traitlets.config.loader.ArgParseConfigLoader.load_config(self, argv='None', aliases='None', flags='<deprecated>', classes='None')
-
-        - traitlets.traitlets.Dict.element_error(self, obj, element, validator)
-        + traitlets.traitlets.Dict.element_error(self, obj, element, validator, side='Values')
-
-        - traitlets.traitlets.HasDescriptors.setup_instance(self, *args, **kwargs)
-        + traitlets.traitlets.HasDescriptors.setup_instance(*args, **kwargs)
-
-        - traitlets.traitlets.HasTraits.setup_instance(self, *args, **kwargs)
-        + traitlets.traitlets.HasTraits.setup_instance(*args, **kwargs)
-
-        - traitlets.traitlets.TraitType.error(self, obj, value)
-        + traitlets.traitlets.TraitType.error(self, obj, value, error='None', info='None')
-
-
-
-4.3
----
-
-4.3.2
-*****
-
-`4.3.2 on GitHub`_
-
-4.3.2 is a tiny release, relaxing some of the deprecations introduced in 4.3.1:
-
-- using :meth:`_traitname_default()` without the ``@default`` decorator is no longer
-  deprecated.
-- Passing ``config=True`` in traitlets constructors is no longer deprecated.
-
-4.3.1
-*****
-
-`4.3.1 on GitHub`_
-
-- Compatibility fix for Python 3.6a1
-- Fix bug in Application.classes getting extra entries when multiple Applications are instantiated in the same process.
-
-4.3.0
-*****
-
-`4.3.0 on GitHub`_
-
-- Improve the generated config file output.
-- Allow TRAITLETS_APPLICATION_RAISE_CONFIG_FILE_ERROR env to override :attr:`Application.raise_config_file_errors`,
-  so that config file errors can result in exiting immediately.
-- Avoid using root logger. If no application logger is registered,
-  the ``'traitlets'`` logger will be used instead of the root logger.
-- Change/Validation arguments are now Bunch objects, allowing attribute-access,
-  in addition to dictionary access.
-- Reduce number of common deprecation messages in certain cases.
-- Ensure command-line options always have higher priority than config files.
-- Add bounds on numeric traits.
-- Improves various error messages.
-
-
-4.2
----
-
-4.2.2 - 2016-07-01
-******************
-
-`4.2.2 on GitHub`_
-
-Partially revert a change in 4.1 that prevented IPython's command-line options from taking priority over config files.
-
-
-4.2.1 - 2016-03-14
-******************
-
-`4.2.1 on GitHub`_
-
-Demotes warning about unused arguments in ``HasTraits.__init__`` introduced in 4.2.0 to DeprecationWarning.
-
-4.2.0 - 2016-03-14
-******************
-
-`4.2 on GitHub`_
-
-- :class:`JSONFileConfigLoader` can be used as a context manager for updating configuration.
-- If a value in config does not map onto a configurable trait,
-  a message is displayed that the value will have no effect.
-- Unused arguments are passed to ``super()`` in ``HasTraits.__init__``,
-  improving support for multiple inheritance.
-- Various bugfixes and improvements in the new API introduced in 4.1.
-- Application subclasses may specify ``raise_config_file_errors = True``
-  to exit on failure to load config files,
-  instead of the default of logging the failures.
-
-
-4.1 - 2016-01-15
-----------------
-
-`4.1 on GitHub`_
-
-Traitlets 4.1 introduces a totally new decorator-based API for configuring traitlets.
-Highlights:
-
-- Decorators are used, rather than magic method names, for registering trait-related methods. See :doc:`using_traitlets` and :doc:`migration` for more info.
-- Deprecate ``Trait(config=True)`` in favor of ``Trait().tag(config=True)``. In general, metadata is added via ``tag`` instead of the constructor.
-
-Other changes:
-
-- Trait attributes initialized with ``read_only=True`` can only be set with the ``set_trait`` method.
-  Attempts to directly modify a read-only trait attribute raises a ``TraitError``.
-- The directional link now takes an optional `transform` attribute allowing the modification of the value.
-- Various fixes and improvements to config-file generation (fixed ordering, Undefined showing up, etc.)
-- Warn on unrecognized traits that aren't configurable, to avoid silently ignoring mistyped config.
-
-
-4.0 - 2015-06-19
-----------------
-
-`4.0 on GitHub`_
-
-First release of traitlets as a standalone package.
-
-
-
-.. _`4.0 on GitHub`: https://github.com/ipython/traitlets/milestones/4.0
-.. _`4.1 on GitHub`: https://github.com/ipython/traitlets/milestones/4.1
-.. _`4.2 on GitHub`: https://github.com/ipython/traitlets/milestones/4.2
-.. _`4.2.1 on GitHub`: https://github.com/ipython/traitlets/milestones/4.2.1
-.. _`4.2.2 on GitHub`: https://github.com/ipython/traitlets/milestones/4.2.2
-.. _`4.3.0 on GitHub`: https://github.com/ipython/traitlets/milestones/4.3
-.. _`4.3.1 on GitHub`: https://github.com/ipython/traitlets/milestones/4.3.1
-.. _`4.3.2 on GitHub`: https://github.com/ipython/traitlets/milestones/4.3.2
diff --git a/docs/source/conf.py b/docs/source/conf.py
index dd22222e..1193912a 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -16,8 +16,12 @@
 # serve to show the default.
 
 import os
+import shutil
 import sys
 
+HERE = os.path.abspath(os.path.dirname(__file__))
+ROOT = os.path.abspath(os.path.join("../../", HERE))
+
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
@@ -26,7 +30,11 @@
 # We load the ipython release info into a dict by explicit execution
 _release = {}  # type:ignore
 exec(
-    compile(open("../../traitlets/_version.py").read(), "../../traitlets/_version.py", "exec"),
+    compile(
+        open(os.path.join(ROOT, "traitlets/_version.py")).read(),
+        "../../traitlets/_version.py",
+        "exec",
+    ),
     _release,
 )
 
@@ -38,8 +46,9 @@
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
-sys.path.insert(0, os.path.abspath("../sphinxext"))
+sys.path.insert(0, os.path.abspath(os.path.join(HERE, "sphinxext")))
 extensions = [
+    "myst-parser",
     "sphinx.ext.autodoc",
     "sphinx.ext.intersphinx",
     "sphinx.ext.napoleon",
@@ -139,7 +148,7 @@
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-# html_theme = 'alabaster'
+html_theme = "pydata_sphinx_theme"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -314,13 +323,7 @@
 # Example configuration for intersphinx: refer to the Python standard library.
 intersphinx_mapping = {"https://docs.python.org/": None}
 
-# Read The Docs
-# on_rtd is whether we are on readthedocs.org, this line of code grabbed from docs.readthedocs.org
-on_rtd = os.environ.get("READTHEDOCS", None) == "True"
-
-if not on_rtd:  # only import and set the theme if we're building docs locally
-    import sphinx_rtd_theme  # type:ignore[import]
 
-    html_theme = "sphinx_rtd_theme"
-    html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
-# otherwise, readthedocs.org uses their theme by default, so no need to specify it
+def setup(app):
+    dest = os.path.join(HERE, "other", "changelog.md")
+    shutil.copy(os.path.join(HERE, "..", "..", "CHANGELOG.md"), dest)

From 510ad9900fe3faaccf39ef08babafcd314adfd39 Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Sat, 8 Oct 2022 06:23:00 -0500
Subject: [PATCH 2/4] more docs cleanup

---
 .github/workflows/tests.yml |  13 +++
 .gitignore                  |   1 +
 docs/environment.yml        |   8 --
 docs/source/conf.py         |  18 ++--
 docs/source/stats.rst       | 167 ------------------------------------
 docs/source/utils.rst       |   1 +
 pyproject.toml              |   5 ++
 readthedocs.yml             |  16 ++--
 8 files changed, 40 insertions(+), 189 deletions(-)
 delete mode 100644 docs/environment.yml
 delete mode 100644 docs/source/stats.rst

diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index b181e7ed..96a817fe 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -62,6 +62,19 @@ jobs:
       - name: Run the unit tests
         run: pytest -vv -W default traitlets || pytest -vv -W default traitlets --lf
 
+  docs:
+    timeout-minutes: 10
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+      - name: Install the Python dependencies
+        run: |
+          pip install -e .[docs]
+      - name: Build the docs
+        run: |
+          make -C docs html SPHINXOPTS='-W'
+
   test_prereleases:
     name: Test Prereleases
     timeout-minutes: 10
diff --git a/.gitignore b/.gitignore
index 8c8170e2..6fae1b19 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,3 +19,4 @@ __pycache__
 .coverage
 .cache
 htmlcov
+docs/source/CHANGELOG.md
diff --git a/docs/environment.yml b/docs/environment.yml
deleted file mode 100644
index 2fc2bdc2..00000000
--- a/docs/environment.yml
+++ /dev/null
@@ -1,8 +0,0 @@
-name: traitlets
-channels:
-  - conda-forge
-  - conda
-dependencies:
-  - python=3
-  - sphinx
-  - sphinx_rtd_theme
diff --git a/docs/source/conf.py b/docs/source/conf.py
index 1193912a..dd6e79d9 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -16,11 +16,12 @@
 # serve to show the default.
 
 import os
+import os.path as osp
 import shutil
 import sys
 
-HERE = os.path.abspath(os.path.dirname(__file__))
-ROOT = os.path.abspath(os.path.join("../../", HERE))
+HERE = osp.abspath(osp.dirname(__file__))
+ROOT = osp.dirname(osp.dirname(HERE))
 
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
@@ -31,7 +32,7 @@
 _release = {}  # type:ignore
 exec(
     compile(
-        open(os.path.join(ROOT, "traitlets/_version.py")).read(),
+        open(osp.join(ROOT, "traitlets/_version.py")).read(),
         "../../traitlets/_version.py",
         "exec",
     ),
@@ -46,13 +47,12 @@
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
-sys.path.insert(0, os.path.abspath(os.path.join(HERE, "sphinxext")))
+sys.path.insert(0, osp.abspath(osp.join(HERE, "sphinxext")))
 extensions = [
-    "myst-parser",
+    "myst_parser",
     "sphinx.ext.autodoc",
     "sphinx.ext.intersphinx",
     "sphinx.ext.napoleon",
-    "github",  # for easy GitHub links
 ]
 github_project_url = "https://github.com/ipython/traitlets"
 
@@ -99,7 +99,7 @@
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = None
+language = "en"
 
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:
@@ -325,5 +325,5 @@
 
 
 def setup(app):
-    dest = os.path.join(HERE, "other", "changelog.md")
-    shutil.copy(os.path.join(HERE, "..", "..", "CHANGELOG.md"), dest)
+    dest = osp.join(HERE, "changelog.md")
+    shutil.copy(osp.join(HERE, "..", "..", "CHANGELOG.md"), dest)
diff --git a/docs/source/stats.rst b/docs/source/stats.rst
deleted file mode 100644
index edbb6877..00000000
--- a/docs/source/stats.rst
+++ /dev/null
@@ -1,167 +0,0 @@
-We closed 5 issues and merged 115 pull requests.
-The full list can be seen `on GitHub <https://github.com/ipython/traitlets/issues?q=milestone%3A5.0>`__
-
-The following 34 authors contributed 465 commits.
-
-* Adam Chainz
-* Albert Zeyer
-* Aliaksei Urbanski
-* Benjamin Ragan-Kelley
-* Carol Willing
-* Christian Clauss
-* Conner Cowling
-* Dan Allan
-* David Brochart
-* Francisco de la Peña
-* Frédéric Chapoton
-* Hans Moritz Günther
-* Jake VanderPlas
-* Jason Grout
-* Jeroen Demeyer
-* Kevin Bates
-* Kostis Anagnostopoulos
-* Kyle Kelley
-* Leo Gallucci
-* Leonardo Uieda
-* Lumir Balhar
-* maartenbreddels
-* martinRenou
-* Matthias Bussonnier
-* Ryan Morshead
-* Sylvain Corlay
-* Thomas Aarholt
-* Thomas Kluyver
-* Tim Paine
-* Todd
-* Travis DePrato
-* Vidar Tonaas Fauske
-* William Krinsman
-* Yves Delley
-
-GitHub issues and pull requests:
-
-Pull Requests (115):
-
-* :ghpull:`576`: more removal of Python 2 specificity
-* :ghpull:`575`: finish first pass on whats new
-* :ghpull:`574`: more version_info removal
-* :ghpull:`573`: Some removal of Python 2 compatibility (in particular six)
-* :ghpull:`572`: review a few more PRs.
-* :ghpull:`570`: review more PRs changelog and reorder
-* :ghpull:`571`: remove PY2 compat + isort + pyupgrade + darker
-* :ghpull:`567`: fixup changelog
-* :ghpull:`566`: Changelog part 1
-* :ghpull:`565`: Fix doc formatting.
-* :ghpull:`563`: Stop testing traittypes which fails.
-* :ghpull:`562`: Travis CI: Fix Travis build configuration validation issues
-* :ghpull:`561`: Travis CI: Run tests on Python 3.8, not 3.7
-* :ghpull:`543`: Travis CI: Test the current versions of Python
-* :ghpull:`531`: Update myapp.py
-* :ghpull:`546`: Export Bunch
-* :ghpull:`547`: Unpin Python 3.5 for docs
-* :ghpull:`559`: Start testing on current Python versions.
-* :ghpull:`556`: add callable test for master
-* :ghpull:`542`: typo
-* :ghpull:`515`: Add trait-names autocompletion support
-* :ghpull:`529`: Minor addition to docs
-* :ghpull:`528`: Fix formatting.
-* :ghpull:`526`: Fix tests for ipywidgets
-* :ghpull:`525`: Fix backward compatibility and tests
-* :ghpull:`522`: Expose loaded config files, make load idempotent
-* :ghpull:`524`: Fix SyntaxWarning: "is" with a literal.
-* :ghpull:`523`: DOC: Add Callable to docs.
-* :ghpull:`509`: do not catch system exceptions like KeyboardInterrupt
-* :ghpull:`501`: Preserve Class Repr After ``add_traits``
-* :ghpull:`517`: Use log from parent in LoggingConfigurable.
-* :ghpull:`516`: Fix CI
-* :ghpull:`510`: remove one useless return line
-* :ghpull:`493`: Include LICENSE file in wheels
-* :ghpull:`491`: Add missing ``default`` import to run the example
-* :ghpull:`489`: Update link to enthought trait library
-* :ghpull:`484`: Add imports to "Using Traitlets" docs
-* :ghpull:`482`: Fix copy(HasTraits) by copying ``_trait_values`` dict
-* :ghpull:`483`: Appveyor has started failing when upgrading ``pip``
-* :ghpull:`473`: test some downstream projects
-* :ghpull:`464`: Drop dependency on decorator package
-* :ghpull:`462`: drop Python 3.3, update to use 3.6
-* :ghpull:`458`: Add Sphinx extension and autogen function for documenting config options
-* :ghpull:`453`: Remove extra backtics from class link
-* :ghpull:`407`: fix flags & aliases with the same name
-* :ghpull:`438`: fix(help): finish #381 for RsT to print enum-choices
-* :ghpull:`393`: Link tranform
-* :ghpull:`440`: Fix getting class for deprecation warning
-* :ghpull:`436`: Fix overriding ``_trait_default`` method
-* :ghpull:`437`: Don't call notify_change with non-change events
-* :ghpull:`434`: disable cross-validation of defaults
-* :ghpull:`413`: Has Trait Value Method
-* :ghpull:`416`: whitelist traitlets exports
-* :ghpull:`426`: Explain the casing/substring matching of Enums on help-msgs and errors
-* :ghpull:`424`: refact(log): consolidate some duplicate log statements
-* :ghpull:`430`: Fix parsing of deprecated list options failing with empty strings
-* :ghpull:`433`: fix(help): a yield had been forgotten from #405
-* :ghpull:`422`: fix(help): minor typo in print_examples()
-* :ghpull:`420`: BUG: remove redundant call to List.validate_elements
-* :ghpull:`418`: remove incorrect version arg from json config doc
-* :ghpull:`415`: follow mro for trait default generators
-* :ghpull:`414`: fix instance error message
-* :ghpull:`402`: Better Errors for Nested Traits
-* :ghpull:`405`: feat(app): provide help-functions also as generators of text-lines
-* :ghpull:`406`: update pip before install
-* :ghpull:`404`: Tell about help-all last.
-* :ghpull:`371`: New FuzzyEnum trait that matches case-insensitive prefixes/substrings
-* :ghpull:`392`: style(cfg): apply review items in #385 for gen-config
-* :ghpull:`384`: add ``trait_values`` method
-* :ghpull:`399`: test on appveyor
-* :ghpull:`391`: Suppress Redundant Configurable Validation
-* :ghpull:`341`: add Application.show_config[_json]
-* :ghpull:`396`: Ensure config loader tests include unicode
-* :ghpull:`394`: Add link method to link and dlink
-* :ghpull:`398`: explain which singleton is already instanciated
-* :ghpull:`385`: generate all config, not just new traits on each class
-* :ghpull:`383`: notify on default creation
-* :ghpull:`381`: feat(cfg): write also enum choices when generating config.py files
-* :ghpull:`257`: [WIP] make This inherit from Instance and add ThisType
-* :ghpull:`380`: feat(app): iterate Configurable base-classes for non ``app.classes`` lists
-* :ghpull:`368`: README: Addd links-table from index, improve opening
-* :ghpull:`365`: FIX: KVConfigLoader could not handle lone dashes('-') as extra arguments
-* :ghpull:`364`: Re-enable TC-code for subcmds forgotten by #362
-* :ghpull:`367`: Fix a bug in TraitType.default
-* :ghpull:`362`: Support callable subcommands
-* :ghpull:`361`: help: Alias overriding help-text (like flags), options list human-help before automated infos
-* :ghpull:`360`: Add factory method on Application for customizing the Loader parsing cmd-line args
-* :ghpull:`354`: Improve generated help and config messages
-* :ghpull:`359`: Pin docs build to Python 3.5
-* :ghpull:`356`: Allow "cls" and "self" as keyword argument in __new__
-* :ghpull:`346`: invert class/instance initialize priority in union "subtraits"
-* :ghpull:`347`: test union valdiation priority
-* :ghpull:`353`: Don't warn about correctly decorated default-value generators
-* :ghpull:`355`: Merge class config dicts when flattening flags
-* :ghpull:`350`: further clarify Dict docstring
-* :ghpull:`306`: added a key_trait argument to Dict
-* :ghpull:`340`: reintroduce deprecated support for old-style container args
-* :ghpull:`338`: [proposal] Make new argparse container CLI opt-in
-* :ghpull:`349`: Consolidated TraitType Defaults Into One Generator
-* :ghpull:`343`: Any should allow None by default
-* :ghpull:`332`: Create All Default Values With Generators
-* :ghpull:`337`: Enable deprecation warnings during test-suite.
-* :ghpull:`339`: nicer repr of LazyConfigValues
-* :ghpull:`333`: Add a Callable Trait
-* :ghpull:`322`: Use argparse to configure container-traits from command-line
-* :ghpull:`331`: Update examples to use an IPython config option which still exists
-* :ghpull:`330`: Convert readthedocs links for their .org -> .io migration for hosted projects
-* :ghpull:`329`: setup.py - set url to github repo
-* :ghpull:`319`: app: support flags/aliases given as (--long, -short) tuple
-* :ghpull:`320`: docs: Move changelog as /CHANGES.rst
-* :ghpull:`324`: Add more cross-validation examples
-* :ghpull:`323`: use simpler callable check for meta_eval
-* :ghpull:`316`: Test on nightly and allow_failure.
-* :ghpull:`299`: casting traits inherit from mixin
-* :ghpull:`311`: use pip_install in readthedocs.yml
-
-Issues (5):
-
-* :ghissue:`287`: Default values are not cross-validated with ``@validation``
-* :ghissue:`363`: Traitlets master breaks ipywidgets
-* :ghissue:`417`: buggy recommendation for version param in json config traitlets/docs/source/config.rst
-* :ghissue:`342`: Test failures in jack-of-none
-* :ghissue:`256`: how to extend dynamic defaults with super
diff --git a/docs/source/utils.rst b/docs/source/utils.rst
index 1e2d3143..76c8b419 100644
--- a/docs/source/utils.rst
+++ b/docs/source/utils.rst
@@ -2,6 +2,7 @@ Utils
 =====
 
 .. module:: traitlets
+   :noindex:
 
 A simple utility to import something by its string name.
 
diff --git a/pyproject.toml b/pyproject.toml
index 2736ed79..0c333bb8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -22,6 +22,11 @@ dynamic = ["description", "version"]
 
 [project.optional-dependencies]
 test = ["pytest", "pre-commit"]
+docs = [
+    "myst-parser",
+    "pydata-sphinx-theme",
+    "sphinx"
+]
 
 [tool.hatch.version]
 path = "traitlets/_version.py"
diff --git a/readthedocs.yml b/readthedocs.yml
index 115fc4f2..5062fcd5 100644
--- a/readthedocs.yml
+++ b/readthedocs.yml
@@ -1,8 +1,14 @@
-conda:
-  file: docs/environment.yml
-python:
-  version: 3
-  pip_install: true
+version: 2
+sphinx:
+  configuration: docs/source/conf.py
 formats:
   - epub
   - pdf
+python:
+  version: 3.8
+  install:
+    # install itself with pip install .
+    - method: pip
+      path: .
+      extra_requirements:
+        - docs

From 48c3cdd56ff5e9ff9e38ed8abe7aeddd6560419b Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Sat, 8 Oct 2022 06:30:30 -0500
Subject: [PATCH 3/4] lint

---
 docs/source/conf.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/docs/source/conf.py b/docs/source/conf.py
index dd6e79d9..1f74bd82 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -15,7 +15,6 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
-import os
 import os.path as osp
 import shutil
 import sys

From 3e7abaefa24082fd545d39702bfead89b12e15a1 Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Sat, 8 Oct 2022 06:37:44 -0500
Subject: [PATCH 4/4] remove unused reqs file

---
 docs/requirements.txt | 4 ----
 1 file changed, 4 deletions(-)
 delete mode 100644 docs/requirements.txt

diff --git a/docs/requirements.txt b/docs/requirements.txt
deleted file mode 100644
index f9d5d75b..00000000
--- a/docs/requirements.txt
+++ /dev/null
@@ -1,4 +0,0 @@
--e ../.
-myst-parser
-pydata-sphinx-theme
-Sphinx