In Zope4 error_message is sometimes not passed.

( also http exceptions are callable but that was fixed in
3cffb52c  xhtml: the exception in error_value is callable and evaluated, prevent it when rendering page [aurel]
maybe we can squash these two commits later )

This reverts commit eaae74a0.

On Zope4 branch we are ready to use __code__

Globals module no longer exists. There are no users of
Globals.get_request anymore

This supports both python2 and python3. For python3, this decode() properly
arguments returned by string_literal() to have str(), otherwise the query string
is an str() (DocumentTemplate) and the arguments are bytes().

In other places, bytes() is used directly but in this case this is not needed
and would require monkey patching (at least) DocumentTemplate.

This changes slightly getOutput, `Status` is not printed as an header
(Status: 200 OK) but only in the status line (HTTP/1.1 200 OK)

In case of ConflictError, request will be retied for
HTTPRequest.retry_max_count times. For Zope 2, the default value of the
class attribute was 3, but on Zope 4, default value is 0 and this is set
to 3 on startup (by Zope2.Startup.handlers.root_wsgi_handler).
This startup code is not executed by runUnitTest, we need to set
HTTPRequest.retry_max_count somewhere, otherwise ConflictError are not
retried during tests.

The status message no longer use system-msg class, use simpler
"assertTextPresent" that should be enough.

Simplify the waiting for static pages, clickAndWait is enough.

I'll make a commit to handle all tests

With zope.tal 3.6.0 - commit 26fadc4 (Increase the default value of
the `wrap` argument from 60 to 1023 characters, to avoid extra
whitespace and line breaks., 2011-08-20) from zopefoundation/zope.tal -
page templates keep the attributes on the same line and produce
slightly different output, although equivalent.

This commit updates the places where we do snapshot testing to the
new output. We discussed using lxml features to compare html and xml
from https://lxml.de/lxmlhtml.html#running-html-doctests but because
the corporate identity web pages are invalid html, it seems unsafe
to rely on lxml at this point. Once corporate identity web pages
are fixed this would probably be a good thing to do.

zope.conf of Zope2 (zopeschema.xml) used to define event/Z2 log files and
properly configure logging but this is not the case anymore with
Zope4 (wsgischema.xml).

This adds path to event/Z2 log files as command line parameter as we probably
don't need further configuration such as message format (SlapOS recipe has never
handled it anyway).

Also, `__code__` has been introduced in Python 2.6 (for forwards compatibility
with Python 3) as an alias to func_code which has been completely removed in
Python 3.

This fixes testFunctionalCore failures:
  [...]
    Module ZPublisher.mapply, line 53, in mapply
      code = f.__code__
  AttributeError: 'DefaultGetter' object has no attribute '__code__'

See Revert "zope patches: display OFSFile content using full available height in zmi".

This fixes testBigFile failures because of `size` not being set to 0 when `data`
is set to None.

Modify DTML templates likewise Zope4 removal commit:
  commit 1df76c1ea8911d7d9249eb6beab1fafd4ed5803c
  Author: Hanno Schlichting <hanno@hannosch.eu>
  Date:   Sun Jul 3 14:19:26 2011 +0000
      Removed `bobobase_modification_time` from `Persistence.Persistent`, you can use `DateTime(object._p_mtime)` instead.

This fixes failure on test_PROPFIND_on_document (testWebDavSupport).

also use the same pattern of clickAndWait and assertElementPresent
in all places, sometimes we used click and waitForElementPresent,
which should be equivalent because we click on a top level navigation
link

This reverts commit 8f5497d4.

This is not longer needed - with Zope 4 the ZMI is better and we now
have possibility to edit most of these through ERP5 user interface.
The main motivation is that these kind of patches are really hard to
keep up to date.

This reverts commit 88786a70.

This is not longer needed - with Zope 4 the ZMI is better and we now
have possibility to edit most of these through ERP5 user interface.
The main motivation is that these kind of patches are really hard to
keep up to date.

This reverts commit c89e308f.

This is not longer needed - with Zope 4 the ZMI is better and we now
have possibility to edit most of these through ERP5 user interface.
The main motivation is that these kind of patches are really hard to
keep up to date.

In the changes from ExternalMethod 2.13.1 -> 4.5, now ExternalMethod
define __code__ (and __defaults__) to a computed attribute calling
getFunction, but getFunction is different in our patched class, so
when unwrapMethod tries to get __code__, it will raise and mapply
will not consider the external method as being callable, so a simple
__repr__ of the ExternalMethod will be used as response body when
published.

By defining __code__ to something using our patched logic, this
problem does not happen.

Utility function taking care of the internal changes between RestrictedPython v3
and v5, keeping support for both (instead of having multiple if statements).