Add editor option to allow selection highlighting of multiline selections and another option to control max length

[g0t4]

Currently, multiline highlights (of selection matches) aren't possible. Multiline is explicitly disabled with a claim of performance but in my initial testing everything seems fine. What does it matter if a selection is 10 chars and happens to have a newline in it versus not? Especially considering the fact that you can search for a multiline string without any problems, so why would this be any different?

Furthermore, the max length of a highlight was hard coded to 200 chars. I added another option for that. Including the option to not limit the length.

I will do further analysis of these changes to see if anything else is impacted. So far it works great!

FYI this has been previously discussed #10588 with no resolution and a closed ticket.

Default values

I set the new defaults to mirror current behavior that:

• disables multiline
• limits to 200 characters.

But, I believe we could increase the max length. Perhaps someone could run performance tests to see if there are any issues with 1000s to 10000s of characters.

Alternative approach

• Another approach would be to lift the restriction on multiline and get rid of the new option. Just always allow it
• Perhaps even allow unlimited length unless some tests can show its a problem?

Understandings

• FYI minimap doesn't highlight similar matches of a selection. It only highlights actual selection(s), find matches and one word matches. So, no changes for this.
• FYI, when using multiple cursors, after adding a second cursor any highlights from the first cursor+selection disappear. So, no changes either.

Example

[g0t4]

@microsoft-github-policy-service agree