Strip indentation and leading/trailing spaces/linebreaks from contents of blocktrans block.

[Dmitri Fedortchenko <zeraien@…>]

The idea is to strip whitespace indentation from the contents of the blocktrans tag, as well as leading and trailing whitespace and linebreaks.

Blocktrans tags allow you to split your translation strings onto multiple lines and this is a good feature, especially if using the "plural" mode.

Picture this:

{% blocktrans number as count %}
There is {{count}} message
waiting for you
{% plural %}
There are {{count}} messages
waiting for you
{% endblocktrans %}

The biggest issue is if you indent the above block. Suddenly those msgids are obsolete and you need to edit all your language files....

Indentation is often changed in HTML since you might nest that block in a new DIV element or whatnot, and the ability to spread the msgids along many lines makes for cleaner looking code.

Furthermore, the current blocktrans tag implementation generates some ugly translation strings when using make-messages if you have indented your msgid block.
Since most HTML is somehow indented, the above can easily look like this:

msgid "\n"
"\t\t\t\t\tThere are %(count)s messages\n"
"\t\t\t\t\twaiting for you\n"
"\t\t\t\t\t"

Note the last line of tabs, since it includes the indentation of the "endblocktrans" tag as well.

See this thread for more:
​http://groups.google.com/group/django-developers/browse_thread/thread/60f0a0ac2347c5f5

[Dmitri Fedortchenko <zeraien@…>]

Patch that adds stripping of indentation from contents of blocktrans block.

[Dmitri Fedortchenko <zeraien@…>]

Some unit tests to show and test outcome of stripping process

[Simon G <dev@…>]

Accepted, with a possible improvements depending on MT's judgement :)

[Dmitri Fedortchenko <zeraien@…>]

I would like to start by pointing out that as it is right now, the patch breaks a few blocktrans msgids from the admin app.
However I feel that it might be worth it anyway, and I am sure there can be a workaround. Perhaps a transitional period where two checks are made, one with stripping and then a second AS IS if the first fails...

[Dmitri Fedortchenko <zeraien@…>]

Original patch could not be applied after rev 6689, this is an update.

[Simon Charette]

I happen to use blocktrans template tag in a non-html template where indentation is important.

What about adding a spaceless_blocktrans block? It would maintain backward compatibility while fixing this issue.

[Vlada Macek]

I also hate those \t's and \n's in blocktrans! When passing PO's to 3rd party translation agencies, they're not always able to handle escapes correctly.

To avoid \t's and \n's, I'm forced to have blocktranses on a single line. With plural form and variable interpolation it can easily become 300 chars line!

If we want to stay backwards compatible and not adding any new tag, wouldn't it be possible to add a "trimmed" option inside the blocktrans option?

Something like: {% blocktrans trimmed ... %}

It would:

• strip all whitespace from start and end of the string,
• do s/[\t\n]+/ /g

Just as the browser does.

Thanks for consideration. (I also dare to change the ticket properties.)

[Danilo Bargen]

I think both a blocktrans argument or a new tag would be acceptable.

[Benedikt Breinbauer]

Replying to Dmitri Fedortchenko <zeraien@…>:

The biggest issue is if you indent the above block. Suddenly those msgids are obsolete and you need to edit all your language files....

Indentation is often changed in HTML since you might nest that block in a new DIV element or whatnot, and the ability to spread the msgids along many lines makes for cleaner looking code.

Another problem that I haven't seen mentioned, that is implied above: The same blocktrans text could be used at different indentation levels and gets interpreted as different msgids, thus needs to be translated more than necessary.

[Apostolis Bessas]

Pull request updated: ​https://github.com/django/django/pull/803

[Bouke Haarsma]

Pull request rebased: ​https://github.com/django/django/pull/1773

[Bouke Haarsma]

RFC as review comments by aaugustin have been solved

[Anssi Kääriäinen <akaariai@…>]

In 7a7c789d5a7ce1c62e3739cb2624454189410ece:

Fixed #5849 -- Strip whitespace from blocktrans

Add the trimmed option to the blocktrans tag to trim any newlines and
whitespace from its content.

This allows the developer to indent the blocktrans tag without adding
new lines and whitespace to the msgid in the PO file.

Thanks to mpessas for the initial patch and Dmitri Fedortchenko for the
report.