word wrap in preview window

[korakinos]

I'd like to have the option to get word wrap in the preview window (i.e. wrapping text on whitespace only). For prose text files, I would much prefer this over default behaviour of --preview-window=wrap to fill lines completely.

Is there a way to achieve this already? I couldn't find one.

If there isn't a way yet, I'm not sure which of these two features to request:

1. Word wrap support in fzf itself (e.g. --preview-window=word-wrap).
2. A way to inform preview commands about the current width of the preview window, possibly with a brace syntax like {width}, so that one could use a tool like fmt or fold to wrap a file: --preview "fmt -w {width} {}".

[junegunn]

fzf/man/man1/fzf.1

Lines 545 to 549 in dd59b8c

	fzf exports \fB$FZF_PREVIEW_LINES\fR and \fB$FZF_PREVIEW_COLUMNS\fR so that
	they represent the exact size of the preview window. (It also overrides
	\fB$LINES\fR and \fB$COLUMNS\fR with the same values but they can be reset
	by the default shell, so prefer to refer to the ones with \fBFZF_PREVIEW_\fR
	prefix.)

[korakinos]

Perfect, thanks a lot! I should have read the manual more thoroughly.

[allefeld]

Access to the preview window width doesn't solve the word wrap problem generally, because as far as I can tell, none of the standard text word wrap filter programs – I looked at fmt and fold – can deal with ANSI color codes, leading to unnecessarily short lines if applied e.g. to colored grep results. Moreover, none have the ability to prefix wrapped lines like fzf does with --wrap-sign= (hanging indent).

So, it would imho still be great if fzf could implement word wrapping.

Another small quibble I have with fzf's wrapping is that scrolling moves by original lines, not wrapped lines. For very long lines, e.g. search results from Markdown files, this has a jarring effect.

I'm happy to create issues if that helps.

[junegunn]

Someone should be interested in writing a next-gen word wrap filter program that addresses the needs. Then it could be used with fzf, but also independently, embracing the Unix philosophy.

[allefeld]

I'll take that as a "no". ;-)

I've searched for an external tool, but didn't find anything.
less can do it, but I wasn't able to access that functionality outside of displaying on screen. As soon as the output is piped, the wrapping is lost.
I've written a hacky version in bash which can deal with grep search results, but not a general solution.
A general solution could be based on the ansiwrap Python package, but that is unmaintained.

[junegunn]

I'm exploring alternative approaches and evaluating their merit. fzf embraces the Unix philosophy by delegating to other specialized programs (like bat, ripgrep, etc) as much as possible, but it's not clear this wrapping is a good fit for delegation. So I'm still undecided.