[clang-tidy] Fix readability-redundant-string-cstr for smart pointer #576705

[mikecrowe]

Summary

Fix the readability-redundant-string-cstr check to correctly replace
calls to c_str() via an overloaded operator-> (such as from an
iterator.)

Previously, the fix for i->c_str() would be *i->. Using consume_back
to remove any trailing -> results in the correct *i.

Add some lit check test cases too.

Fixes: https://github.com/llvm/llvm-project/issues/56705

[PiotrZSL]

Also consider reducing commit message, instead just copying issue description.
Simple description about issue would be sufficient.

No functional issues, so LGTM.

clang-tools-extra/clang-tidy/readability/RedundantStringCStrCheck.cpp

56

You don't need to reference issue (it's already in commit message) here, better comment like "// Removing remaining '->' from overloaded operator call"

[mikecrowe]

In D145730#4182949, @PiotrZSL wrote:

Also consider reducing commit message, instead just copying issue description.
Simple description about issue would be sufficient.

TBH, I wasn't expecting this change to be accepted. I was merely hoping that it would cause someone to give me a hint as to how to fix it properly. That's why I included so much information in the commit message. I will shorten the commit message.

No functional issues, so LGTM.

Thanks for the review.

[PiotrZSL]

Code is correct, simply this check uses more manual string manipulation.
In theory there could be some more issues if operator -> wouldn't return pointer, but a class with additional operator ->, but that's legacy independent issue.

[mikecrowe]

Fix comment in code as suggested by PiotrZSL. Improve lit check tests.

[mikecrowe]

Thanks for the speedy re-review. I don't have commit permission, so please can you land this if you are happy to do so?

[mikecrowe]

Thanks, and sorry about the erroneous [PATCH] in the summary. :(