Hello up there. To test my module that computes diff for BTrees I was playing
with manually creating BTrees with different topologies[1,2] and hit the
following bug that was leading to segmentation faults:

C implementation of Tree.__setstate__ allows to pass in arbitrary objects in
place of children and casts child to (Bucket*) if child type is not type of the
tree

    _without further checking that type of the child is actually Bucket_

This leads to crashes when later the code, that is accessing tree nodes,
goes to leafs, accesses passed in objects assuming they are buckets with
corresponding C-level Bucket structure layout, and oops dereferences e.g.
Bucket->keys, or Bucket->values from memory initialized via non-Bucket
C-level data.

-> Fix it by allowing to pass into tree.__setstate__ only children of
either tree or bucket types.

Note: for tree kind the type is checked exactly, because in many places C
implementation already does `if (SameType_Check(tree, X))` and assumes X is
of bucket kind if that check fails. For buckets we accept tree._bucket_type
subclasses as they are handled correctly and bucket type for tree.firstbucket
is already verified via "isinstance".

Kirill

P.S.

test___setstate___to_multiple_buckets is adjusted to avoid test failures
because Test_Tree._makeOne() was creating tree with ._bucket_type different
from _Bucket defined in that test.

[1] https://lab.nexedi.com/kirr/wendelin.core/blob/28010b7/wcfs/internal/xbtree.py
[2] https://lab.nexedi.com/kirr/wendelin.core/blob/28010b7/wcfs/internal/xbtree_test.py

/helped-by @jamadden

Fix #140 by turning OverflowError into TypeError.

This only showed up on Windows (because it follows the LLP64 data model). See https://ci.appveyor.com/project/mgedmin/btrees/builds/31998447/job/m3xs7q1d8b4u5u3b

Fingers crossed for 32-bit builds on Windows.

Ensure resolution order for all objects is consistent

Fixes #137.

Fixed tox 'docs' environment

Fix __all__

Python 3: Stop using undocumented PyLong_AS_LONG.

Add unit tests for it and run the documentation tests that originaly caught the problem in CI.

Fixes #132

Since https://github.com/zopefoundation/persistent/issues/125 this would result in compiler warnings.

No change note, this is an internal change.

Fixes #131

Added internal documentation links

Remove most all the boilerplate required to add new trees

Developper documentation improvements

Generate the Python modules and test modules based off a description
of the datatype.

Several tests that were previously only used for a specific classes
are now generalized and added to most trees, such as testing
non-compliant keys and testing overflow for bounded values.

Also always raise ``OverflowError`` for integer keys/values out of range.

And some other small tweaks to the documentation to make cross-references work and things generally look good.

test__UUBTree.py is complete and passing on Python 3

Fix it.

Also it's possible to statically know the expected value of using64bits for all included tree modules, so we don't need the (unexecuted) branch that creates (unused) test code in the *I* test modules.

And other small tweaks to bring test coverage up. Turns out there were several test methods being needlessly skipped.

adds python 3.8 on macos to the travis build.

Fix Python 3.5 MacOS wheel upload

Python 3.5 on Mac OS doesn't support TLS 1.2, which makes twine upload
fail, but we can use system Python 2.7 for twine upload, which works.

Also brings the rest of the Travis CI configuration closer in line to
the rest of the packages updated for
https://github.com/zopefoundation/meta/issues/11

Build using newer manylinux image.