feat: add self keyword to import a module

[g4titanx]

this PR fixes #7279

[reviewable-StarkWare]

This change is 

[orizi]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions

---

a discussion (no related file):
add tests in:
crates/cairo-lang-semantic/src/expr/semantic_test_data/use

should cover both diagnostics for cases it makes no sense, as well usages in cases it does.

---

crates/cairo-lang-semantic/src/resolve/mod.rs line 807 at r1 (raw file):

                return Ok(ResolvedConcreteItem::Module(*module_id));
            }
        }

handle enum as well.

makes sure this is not happening in other cases. (such as a trait or an impl).

Suggestion:

        // Handle the 'self' keyword in import paths - resolves to the containing module
        if ident == SELF_KW {
            // match instead of if let here.
            if let ResolvedConcreteItem::Module(module_id) = containing_item {
                return Ok(ResolvedConcreteItem::Module(*module_id));
            }
        }

[g4titanx]

hey @orizi, when running the tests, I'm getting failures because the tests are expecting the original behavior (where self is not recognized as a keyword). I believe I need to run with CAIRO_FIX_TESTS=1 to update the test expectations, did that and i'm still getting the same error message

failures:

---- expr::test::expr_semantics::use_ stdout ----

thread 'expr::test::expr_semantics::use_' panicked at crates/cairo-lang-test-utils/src/parse_test_file.rs:467:5:


Test "Test self keyword in module imports" failed.
In /Users/g4titan/cairo/crates/cairo-lang-semantic/src/expr/semantic_test_data/use:1521.
`expect_diagnostics` is false, but diagnostics were generated:


Test "Test self keyword with nested modules" failed.
In /Users/g4titan/cairo/crates/cairo-lang-semantic/src/expr/semantic_test_data/use:1579.
`expect_diagnostics` is false, but diagnostics were generated:


Test "Test enum with self keyword" failed.
In /Users/g4titan/cairo/crates/cairo-lang-semantic/src/expr/semantic_test_data/use:1643.
`expect_diagnostics` is false, but diagnostics were generated:


Summary: 30 passed, 3 failed:
test_expr_semantics::use::"Test self keyword in module imports" (line: 1521)
test_expr_semantics::use::"Test self keyword with nested modules" (line: 1579)
test_expr_semantics::use::"Test enum with self keyword" (line: 1643)

note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace


failures:
    expr::test::expr_semantics::use_

test result: FAILED. 97 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 4.69s

error: test failed, to rerun pass `-p cairo-lang-semantic --lib`

[orizi]

Reviewable status: 0 of 3 files reviewed, 3 unresolved discussions (waiting on @g4titanx)

---

crates/cairo-lang-semantic/src/expr/semantic_test_data/use line 1524 at r2 (raw file):

//! > test_runner_name
test_expr_semantics(expect_diagnostics: false)

when expecting diagnostics - do this.

Suggestion:

test_expr_semantics(expect_diagnostics: true)

[orizi]

Reviewable status: 0 of 3 files reviewed, 5 unresolved discussions (waiting on @g4titanx)

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crates/cairo-lang-semantic/src/expr/semantic_test_data/use line 1538 at r2 (raw file):

    X::Y;
    Y
}

simplify the others similarly.

Suggestion:

//! > module_code
mod x {
    mod y {
        pub const Z: u8 = 2;
    }
}

use x::y::self;

//! > function_body

//! > expr_code
y::Z

---

crates/cairo-lang-semantic/src/expr/semantic_test_data/use line 1569 at r2 (raw file):

error[E0006]: Identifier not found.
 --> lib.cairo:6:14
    use X::{ self, Y };

this means the actual solution is not correct - i believe you are attempting to resolve during the first step, instead of the last.

Code quote:

    use X::{ self, Y };

[g4titanx]

okay done @orizi
test passed

[orizi]

please reply to everything in https://reviewable.io/reviews/starkware-libs/cairo/7366#-
to keep threads.

Reviewed 1 of 3 files at r2, all commit messages.
Reviewable status: 1 of 3 files reviewed, 5 unresolved discussions (waiting on @g4titanx)

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crates/cairo-lang-semantic/src/expr/semantic_test_data/use line 1569 at r2 (raw file):

Previously, orizi wrote…

this means the actual solution is not correct - i believe you are attempting to resolve during the first step, instead of the last.

there shouldn't be diagnostics here.