Add redundant-test-main-exit rule

[semihbkgr]

The redundant-test-main-exit rule reports unnecessary Exit calls in TestMain functions, as the Go test runner has handled termination automatically since Go 1.15; the details are explained in the issue.

fixes #1189

The deep-exit rule currently excludes reporting Exit calls in TestMain functions, but we could consider updating its behavior to include these calls, which might eliminate the need to define this new rule.

[chavacava]

Hi @semihbkgr thank you for tha PR.

I' ve left some comments.
One more thing, we should only apply the rule if the code under analysis is on a Go version 1.15 or higher. To do so, you can take inspiration in other rules like range-val-in_closure

revive/rule/range_val_in_closure.go

Line 17 in 8cb2599

if file.Pkg.IsAtLeastGo122() {

(that should also be tested)

Thanks again

[chavacava]

isCallToExitFunction will return true even for function calls other than os.Exit (for example log.Fatal, log.Panic ...) That behavior is okay for what we check here?

[semihbkgr]

Hi @chavacava, thank you for your detailed review and suggestions!

I’m not entirely sure about including logging functions other than os.Exit or syscall.Exit. It’s uncommon (in my experience) to call logging functions that internally invoke Exit, but I don't see any downside to including them in this check.

What’s your opinion on this?

[semihbkgr]

The issue with including logging functions is that the common failure message may not be appropriate for them, as these functions are not necessarily redundant: they first log a message and then exit.

[chavacava]

Merged! Thank you @semihbkgr (and @alexandear)