Fix suggestions rendering when the diff span is multiline

[CastilloDel]

Fixes #92741

cc @estebank

I think, I finally fixed it. I still want to go back and try to clean up the code a bit. I'm open to suggestions.

Some examples of the new suggestions:

help: consider removing the borrow
  |
2 -     &
  |

help: consider removing the borrow
  |
2 -     &
3 -     mut
  |

help: consider removing the borrow
  |
2 -     &
3 -     mut if true { true } else { false }
2 +     if true { true } else { false }
  |

Should we add a test to ensure this behavior doesn't disappear in the future?

[rustbot]

r? @WaffleLapkin

(rustbot has picked a reviewer for you, use r? to override)

[CastilloDel]

r? @estebank

I hope you don't mind. It seems simpler, because we already discussed this in the issue

[compiler-errors]

Should we add a test to ensure this behavior doesn't disappear in the future?

Yes, in general, PRs that affect observable behavior should have a UI test associated with it.

[estebank]

After adding more comments (particularly for presentation code, I find that having comments showing what each bit of code visually results in helps me a lot when I try to make changes 6 months later, and I always regret it when I don't find comments) and having some tests for these, I believe we can merge.

[CastilloDel]

I think this PR is mostly finished now. Maybe the test should be in another directory? I couldn't find one that seemed right.

[estebank]

@bors r+

[bors]

📌 Commit 9cdc075 has been approved by estebank

It is now in the queue for this repository.

[estebank]

There is some follow up work here that I'd like to see. I've approved the PR. If you have time before bors merges it, update it and I'll re-approve. If not, lets make a follow up PR.

[CastilloDel]

Should be finished now. Thanks for all the help @estebank!

[WaffleLapkin]

@bors r=estebank

[bors]

📌 Commit f0830c0 has been approved by estebank

It is now in the queue for this repository.

[bors]

⌛ Testing commit f0830c0 with merge 5dd0e1b...

[bors]

☀️ Test successful - checks-actions
Approved by: estebank
Pushing 5dd0e1b to master...

[rust-timer]

Finished benchmarking commit (5dd0e1b): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

This benchmark run did not return any relevant results for this metric.

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-3.5%	[-5.3%, -1.4%]	8
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-3.5%	[-5.3%, -1.4%]	8