Stripping of trailing whitespace affects only some files; no UI indication which types

[jeremypw]

What Happened?

The AppMenu has an option "Strip trailing whitespace on save" which implies that this happens for all documents, which is not the case.

Steps to Reproduce

Activate the stripping option
Create a .txt file with trailing whitespace
Save it
Observe whitespace not stripped

Expected Behavior

The description of the option should include an indication of which file types it applies too or, better, there should be an option for the user to specify which types it applies to (see #617)

OS Version

8.x (Circe)

OS Architecture

amd64 (on most hardwares)

Session Type

Secure Session (Wayland, This is the default)

Software Version

Latest release (I have run all updates)

Log Output

Hardware Info

No response

[Dipanshusinghh]

@jeremypw .
This still seems highly relevant, especially now that #1698 highlights the mismatch between the UI setting and the actual behavior. Markdown/Pandoc is a good example where trailing whitespace can be semantically meaningful,
so making the stripping behavior configurable per file type would likely be a cleaner long-term solution than treating it as a global formatting rule

[jeremypw]

@Dipanshusinghh Yes, stripping takes place (when enabled) for all documents that have an identifiable source language (see line 1318 of Document.vala). We ought to be smarter in identifying those languages where trailing spaces are significant. I am not sure how to efficiently indicate this in the UI or how much fine-grain control is needed. We could, as a first step have a list of languages where stripping is suppressed.

[Dipanshusinghh]

"I completely agree, Jeremy. Having a hardcoded suppression list is a perfect and pragmatic first step to prevent semantic breakages without overcomplicating the UI right away.
We can definitely start by excluding languages where trailing whitespace has structural meaning (like Markdown and perhaps YAML).
I can take a look at Document.vala and try drafting a quick PR to implement this exclusion list if you'd like?

[jeremypw]

@Dipanshusinghh Thanks. If the list of exclusions is not too long then maybe they can be shown in the settings label in the same way as for "smart cut/copy"?