Report line number of test when should_panic test failed

[xizheyin]

Closing #137405

r? @joshka

[rustbot]

Failed to set assignee to joshka: invalid assignee

Note: Only org members with at least the repository "read" role, users with write permissions, or people who have commented on the PR may be assigned.

[rustbot]

Some changes occurred in src/tools/compiletest

cc @jieyouxu

[rustbot]

Could not assign reviewer from: jieyouxu.
User(s) jieyouxu are either the PR author, already assigned, or on vacation. Please use r? to specify someone else to assign.

[jieyouxu]

This looks like a libtest change, so r? libs (or testing-devex?)

[joshka]

Test names are nits, but make the reason for each test self describing.

I think it probably makes sense to also fix the substring tests if they're also broken (I haven't manually checked those messages to see if there's span info coming from elsewhere in the stack, but these seem like they should be tested with the same tests as are introduced here).

[joshka]

Generally LGTM - small nits

(Note: I'm not a member of the rust project, so this likely still requires approval from someone who is)

[jieyouxu]

(Note: I'm not a member of the rust project, so this likely still requires approval from someone who is)

Though reviews are still very much appreciated 😁

[weihanglo]

@bors try

Before the change fails snapshots in Cargo's test testsuite

[bors]

⌛ Trying commit a164290 with merge b7cffdf...

[bors]

☀️ Try build successful - checks-actions
Build commit: b7cffdf (b7cffdfcf2ab6d783e833e46b5dd168197dbcd3e)

[joboet]

I've never touched the test crate before so I don't feel qualified to review this.
r? @thomcc
as you are a member of testing-devex