[methods] Move lints from strings.rs to methods module (#14253)

[paolo9921]

---

changelog: [refactor-strings-lints]: Move lints (except for: string_add, string_add_assign and string_slice (which share an implementation) from clippy_lints/src/strings.rs to the methods module to share tree traversal with other method and function call lints. Fixes #14253.

fixes #14253

[rustbot]

r? @dswij

rustbot has assigned @dswij.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[paolo9921]

Hi, I'm getting this error:
error: callingas_bytes()` on a string literal

• --> tests/ui/string_lit_as_bytes.rs:11:26
• |
  -LL | const B: &[u8] = $b.as_bytes();
• | ^^^^^^^^^^^^^ help: consider using a byte string literal instead: b"warning"
  -...
  -LL | b!("warning");
• | ------------- in this macro invocation
• |
• = note: this error originates in the macro b (in Nightly builds, run with -Z macro-backtrace for more info)

-error: calling as_bytes() on include_str!(..)

• --> tests/ui/string_lit_as_bytes.rs:43:22
• |
  -LL | let includestr = include_str!("string_lit_as_bytes.rs").as_bytes();
• | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using include_bytes!(..) instead: include_bytes!("string_lit_as_bytes.rs")

-error: calling as_bytes() on a string literal

error: diagnostic code clippy::string_lit_as_bytes not found on line 11
--> tests/ui/string_lit_as_bytes.rs:12:14
|
12 | //~^ string_lit_as_bytes
| ^^^^^^^^^^^^^^^^^^^ expected because of this pattern
|

error: diagnostic code clippy::string_lit_as_bytes not found on line 43
--> tests/ui/string_lit_as_bytes.rs:44:10
|
44 | //~^ string_lit_as_bytes
| ^^^^^^^^^^^^^^^^^^^ expected because of this pattern
`

I can't understand.. I have to change the code of the test?

[samueltardieu]

Thanks for the refactoring.

The problem here you are encountering here is twofold:

• Methods::check() calls Methods::check_methods() only if the method call does not come from expanded code.
• methods::check_methods() uses methods::method_call() which returns None if either the method receiver or any of the method argument comes expanded code.

This is done so because to keep the method checking lints simple and less sensitive to subtle bugs, it is simpler to avoid dealing with expanded code. However, in your case, the string_lint_as_bytes lint is supposed to trigger in the presence of a macro as the receiver, or inside a macro.

One possibility would be to apply a commit such as samueltardieu@2e77605 on top of your commit: this introduces the possibility to run some methods lint even in the presence of expansion. Those lints are then in charge of properly checking their context and make sure they behave properly.

[samueltardieu]

Comments in Clippy source code are in English.

[samueltardieu]

You should simply remove unused args.

[rustbot]

☔ The latest upstream changes (possibly d28d234) made this pull request unmergeable. Please resolve the merge conflicts.