Some strings return -1 width

[gauteh]

Hi, we had some issues in sup (sup-heliotrope/sup#157) and it turns out that Unicode.width returns -1 for some strings (sup-heliotrope/sup#256), example (ruby 1.9.3):

> require 'unicode'
> a = 'This is =91 a test: the first line seems to disappear from the mail body but is
still visible in the thread view.'
> Unicode.width a
=> -1
> a.length
=> 113

[blackwinter]

it's caused by the newline. what display width would you expect a multi-line string to have? you could argue that it should be the maximum width of all lines, but then again the specification for wcswidth states that it should return -1 as soon as it encounters a control character.

so i think, whatever it is you actually need, is application specific and should be handled in sup itself.

[gauteh]

Sounds fair, thanks for the explanation.