Building vdirsyncer.drv fails randomly (problem with Hypothesis test framework)

[Tanguy Le Carrour <tanguy@bioneland.org>]

Dear Guix,

When I run `guix package -i vdirsyncer` or `guix package -u` (if vdirsyncer is
in my profile), it randomly fails. This has happened to me several times already.

Here is a part of the log:

============================= test session starts ==============================
platform linux -- Python 3.7.0, pytest-3.8.0, py-1.5.4, pluggy-0.7.1
hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('/tmp/guix-build-vdirsyncer-0.16.7.drv-0/vdirs
yncer-0.16.7/.hypothesis/examples')
rootdir: /tmp/guix-build-vdirsyncer-0.16.7.drv-0/vdirsyncer-0.16.7, inifile: setup.cfg
plugins: hypothesis-3.70.3, localserver-0.5.0, subtesthack-0.1.1
collected 486 items

tests/storage/test_filesystem.py ....................................... [  8%]
.......sss......ss.......                                                [ 13%]
tests/storage/test_http.py .....                                         [ 14%]
tests/storage/test_http_with_singlefile.py ............................. [ 20%]
.........sssssss....sssss.ss                                             [ 25%]
tests/storage/test_memory.py ......................................sssss [ 34%]
ss....sss...ss                                                           [ 37%]
tests/storage/test_singlefile.py ....................................... [ 45%]
.............ss.ss                                                       [ 49%]
tests/storage/dav/test_caldav.py sssssssssssssssssssssssssssssssssssssss [ 57%]
sssssssssssssss                                                          [ 60%]
tests/storage/dav/test_carddav.py ssssssssssssssssssssssssss             [ 65%]
tests/storage/dav/test_main.py .................................         [ 72%]
tests/system/cli/test_config.py .........                                [ 74%]
tests/system/cli/test_discover.py .....                                  [ 75%]
tests/system/cli/test_fetchparams.py .                                   [ 75%]
tests/system/cli/test_repair.py .....                                    [ 76%]
tests/system/cli/test_sync.py ....................                       [ 80%]
tests/system/cli/test_utils.py ..                                        [ 81%]
tests/system/utils/test_main.py .....                                    [ 82%]
tests/unit/test_exceptions.py .                                          [ 82%]
tests/unit/test_metasync.py ........F                                    [ 84%]
tests/unit/test_repair.py ..........                                     [ 86%]
tests/unit/cli/test_config.py .                                          [ 86%]
tests/unit/cli/test_discover.py ......                                   [ 87%]
tests/unit/cli/test_fetchparams.py .........                             [ 89%]
tests/unit/sync/test_status.py .                                         [ 89%]
tests/unit/sync/test_sync.py ...............................             [ 96%]
tests/unit/utils/test_vobject.py ..................                      [100%]

=================================== FAILURES ===================================
_________________________________ test_fuzzing _________________________________
tests/unit/test_metasync.py:129: in test_fuzzing
    a=metadata, b=metadata,
E   hypothesis.errors.FailedHealthCheck: Data generation is extremely slow:
    Only produced 9 valid examples in 1.08 seconds (4 invalid ones and
    0 exceeded maximum size). Try decreasing size of the data you're generating
    (with e.g.max_size or max_leaves parameters).
E   See https://hypothesis.readthedocs.io/en/latest/healthchecks.html for
    more information about this. If you want to disable just this health check,
    add HealthCheck.too_slow to the suppress_health_check settings for this test.


I guess a solution would be to do as they say and deactivate part of the
tests!

What do you guys think?!

-- 
Tanguy