doc: Add history page (#8784)

Based on #8667

doc/en/contents.rst

@@ -95,6 +95,7 @@ Further topics
    license
    contact
 
+   history
    historical-notes
    talks
    projects

doc/en/history.rst

@@ -0,0 +1,147 @@
+History
+=======
+
+pytest has a long and interesting history. The `first commit
+<https://github.com/pytest-dev/pytest/commit/5992a8ef21424d7571305a8d7e2a3431ee7e1e23>`__
+in this repository is from January 2007, and even that commit alone already
+tells a lot: The repository originally was from the `py
+<https://pypi.org/project/py/>`__ library (later split off to pytest), and it
+originally was a SVN revision, migrated to Mercurial, and finally migrated to
+git.
+
+However, the commit says “create the new development trunk” and is
+already quite big: *435 files changed, 58640 insertions(+)*. This is because
+pytest originally was born as part of `PyPy <https://www.pypy.org/>`__, to make
+it easier to write tests for it. Here's how it evolved from there to its own
+project:
+
+
+-  Late 2002 / early 2003, `PyPy was
+   born <https://morepypy.blogspot.com/2018/09/the-first-15-years-of-pypy.html>`__.
+-  Like that blog post mentioned, from very early on, there was a big
+   focus on testing. There were various ``testsupport`` files on top of
+   unittest.py, and as early as June 2003, Holger Krekel (`@hpk42 <https://github.com/hpk42>`__)
+   `refactored <https://mail.python.org/pipermail/pypy-dev/2003-June/000787.html>`__
+   its test framework to clean things up (``pypy.tool.test``, but still
+   on top of ``unittest.py``, with nothing pytest-like yet).
+-  In December 2003, there was `another
+   iteration <https://foss.heptapod.net/pypy/pypy/-/commit/02752373e1b29d89c6bb0a97e5f940caa22bdd63>`__
+   at improving their testing situation, by Stefan Schwarzer, called
+   ``pypy.tool.newtest``.
+-  However, it didn’t seem to be around for long, as around June/July
+   2004, efforts started on a thing called ``utest``, offering plain
+   assertions. This seems like the start of something pytest-like, but
+   unfortunately, it's unclear where the test runner's code was at the time.
+   The closest thing still around is `this
+   file <https://foss.heptapod.net/pypy/pypy/-/commit/0735f9ed287ec20950a7dd0a16fc10810d4f6847>`__,
+   but that doesn’t seem like a complete test runner at all. What can be seen
+   is that there were `various
+   efforts <https://foss.heptapod.net/pypy/pypy/-/commits/branch/default?utf8=%E2%9C%93&search=utest>`__
+   by Laura Creighton and Samuele Pedroni (`@pedronis <https://github.com/pedronis>`__) at automatically
+   converting existing tests to the new ``utest`` framework.
+-  Around the same time, for Europython 2004, @hpk42 `started a
+   project <http://web.archive.org/web/20041020215353/http://codespeak.net/svn/user/hpk/talks/std-talk.txt>`__
+   originally called “std”, intended to be a “complementary standard
+   library” - already laying out the principles behind what later became
+   pytest:
+
+       -  current “batteries included” are very useful, but
+
+          -  some of them are written in a pretty much java-like style,
+             especially the unittest-framework
+          -  […]
+          -  the best API is one that doesn’t exist
+
+       […]
+
+       -  a testing package should require as few boilerplate code as
+          possible and offer much flexibility
+       -  it should provide premium quality tracebacks and debugging aid
+
+       […]
+
+       -  first of all … forget about limited “assertXYZ APIs” and use the
+          real thing, e.g.::
+
+              assert x == y
+
+       -  this works with plain python but you get unhelpful “assertion
+          failed” errors with no information
+
+       -  std.utest (magic!) actually reinterprets the assertion expression
+          and offers detailed information about underlying values
+
+-  In September 2004, the ``py-dev`` mailinglist gets born, which `is
+   now <https://mail.python.org/pipermail/pytest-dev/>`__ ``pytest-dev``,
+   but thankfully with all the original archives still intact.
+
+-  Around September/October 2004, the ``std`` project `was renamed
+   <https://mail.python.org/pipermail/pypy-dev/2004-September/001565.html>`__ to
+   ``py`` and ``std.utest`` became ``py.test``. This is also the first time the
+   `entire source
+   code <https://foss.heptapod.net/pypy/pypy/-/commit/42cf50c412026028e20acd23d518bd92e623ac11>`__,
+   seems to be available, with much of the API still being around today:
+
+   -  ``py.path.local``, which is being phased out of pytest (in favour of
+      pathlib) some 16-17 years later
+   -  The idea of the collection tree, including ``Collector``,
+      ``FSCollector``, ``Directory``, ``PyCollector``, ``Module``,
+      ``Class``
+   -  Arguments like ``-x`` / ``--exitfirst``, ``-l`` /
+      ``--showlocals``, ``--fulltrace``, ``--pdb``, ``-S`` /
+      ``--nocapture`` (``-s`` / ``--capture=off`` today),
+      ``--collectonly`` (``--collect-only`` today)
+
+-  In the same month, the ``py`` library `gets split off
+   <https://foss.heptapod.net/pypy/pypy/-/commit/6bdafe9203ad92eb259270b267189141c53bce33>`__
+   from ``PyPy``
+
+-  It seemed to get rather quiet for a while, and little seemed to happen
+   between October 2004 (removing ``py`` from PyPy) and January
+   2007 (first commit in the now-pytest repository). However, there were
+   various discussions about features/ideas on the mailinglist, and `a
+   couple of
+   releases <https://pypi.org/project/py/0.8.0-alpha2/#history>`__ every
+   couple of months:
+
+   -  March 2006: py 0.8.0-alpha2
+   -  May 2007: py 0.9.0
+   -  March 2008: py 0.9.1 (first release to be found `in the pytest
+      changelog <https://github.com/pytest-dev/pytest/blob/main/doc/en/changelog.rst#091>`__!)
+   -  August 2008: py 0.9.2
+
+-  In August 2009, py 1.0.0 was released, `introducing a lot of
+   fundamental
+   features <https://holgerkrekel.net/2009/08/04/pylib-1-0-0-released-the-testing-with-python-innovations-continue/>`__:
+
+   -  funcargs/fixtures
+   -  A `plugin
+      architecture <http://web.archive.org/web/20090629032718/https://codespeak.net/py/dist/test/extend.html>`__
+      which still looks very much the same today!
+   -  Various `default
+      plugins <http://web.archive.org/web/20091005181132/https://codespeak.net/py/dist/test/plugin/index.html>`__,
+      including
+      `monkeypatch <http://web.archive.org/web/20091012022829/http://codespeak.net/py/dist/test/plugin/monkeypatch.html>`__
+
+-  Even back there, the
+   `FAQ <http://web.archive.org/web/20091005222413/http://codespeak.net/py/dist/faq.html>`__
+   said:
+
+       Clearly, [a second standard library] was ambitious and the naming has
+       maybe haunted the project rather than helping it. There may be a
+       project name change and possibly a split up into different projects
+       sometime.
+
+   and that finally happened in November 2010, when pytest 2.0.0 `was
+   released <https://mail.python.org/pipermail/pytest-dev/2010-November/001687.html>`__
+   as a package separate from ``py`` (but still called ``py.test``).
+
+-  In August 2016, pytest 3.0.0 `was
+   released <https://docs.pytest.org/en/latest/changelog.html#id1313>`__,
+   which adds ``pytest`` (rather than ``py.test``) as the recommended
+   command-line entry point
+
+Due to this history, it's diffcult to answer the question when pytest was started.
+It depends what point should really be seen as the start of it all. One
+possible interpretation is to  pick Europython 2004, i.e. around June/July
+2004.