Subject: bug#37020: 27.0.50; (window-body-width) returns the wrong value with display-line-numbers-mode on

From: Eli Zaretskii <[email-masked]>
Date: Wed, 14 Aug 2019 05:34:23 +0300

tags 37020 notabug
thanks

> From: Lukas Fürmetz <[email-masked]>
> Date: Tue, 13 Aug 2019 22:11:04 +0200
> 
> The title says it all. The function `window-body-width' says in it's
> description, it returns the columns purely of the text window, without
> any margin, fringes etc. But if you turn on display-line-numbers-mode,
> it takes up a lot of space in the margin, but `window-body-width' will
> return the same value as without it.

This is not a bug: the line numbers are part of the text area, and
thus part of the window's body.  If you need to account for the width
taken by the line numbers, you can use the line-number-display-width
function.