Interesting read about final stable release

[Guenter Milde]

On 2019-12-28, José Abílio Matos wrote:
> On Saturday, 13 July 2019 15.52.03 WET Jean-Marc Lasgouttes wrote:
>> [sorry for sending incomplete message earlier]

>> We requested recently that LyX be updated to 2.1.5 in Ubuntu 16.04 LTS,
>> since this branch is stuck with LyX 2.1 anyway. Version 18.04 LTS has
>> already been updated to 2.2.4 recently.

> It took a long time to me to answer that.

> From the Zen of python:

> python -m this

> "Special cases aren't special enough to break the rules.
> Although practicality beats purity."

> We do it because it is practical.

> The change mentioned have been tested in the next stable series, in that case 
> 2.1.5 was only released after 2.2.0 was released.

> Not only that but IIRC we never had any significant bug in the previous code. 

>> However the first answer for 16.04 is negative, and I cannot say that I
>> disagree completely...
>> https://bugs.launchpad.net/ubuntu/+source/lyx/+bug/1595358/comments/20

>> Issues mentioned:
>> * big lyx2lyx update: what testing can we show to make sure that we do
>> not break anything?

> In the particular case of lyx2lyx I compare the output that comes from 
> converting different manual, like the User Guide.

>> * big boost update: at the time it looked like a good idea, but was it?

> The new release has probably has other fixes.

>> * lack of comprehensive tests. We have a few unit tests, and also tests
>> for export, tex2lyx. Do we have real lyx2lyx tests? 

Yes, the ctest suite also contains a large set of lyx2lyx tests.

>> What do we test actually?

lyx2lyx for all Documentation files and some dedicated test samples:

  Test #2560: export/doc/fr/UserGuide_lyx16
  Test #2561: export/doc/fr/UserGuide_lyx20
  Test #2562: export/doc/fr/UserGuide_lyx21
  Test #2563: export/doc/fr/UserGuide_lyx22
  Test #2564: export/doc/fr/UserGuide_lyx23


Current->previous->current round-trips to all formats >= 1.6. must
result in identical output (possibly after some rounds) to pass the test.

Compiling the result of the round-trip for 2.2 and 2.3 formats must work.

>> * basically, cherry-picking a few fixes would be more effective.

>> I let you read, tell me what you think, beyond the "2.1.5 on ubuntu
>> 16.04" issue.

>> JMarc

> In summary I disagree strongly that "basically, cherry-picking a few fixes 
> would be more effective". The maintenance of other projects disproves that 
> view.

Günter