rust/tests/rustdoc/hide-complex-unevaluated-consts.rs
2023-01-11 09:32:08 +00:00

72 lines
2.7 KiB
Rust

// Regression test for issue #97933.
//
// Test that certain unevaluated constant expressions that are
// deemed too verbose or complex and that may leak private or
// `doc(hidden)` struct fields are not displayed in the documentation.
//
// Read the documentation of `rustdoc::clean::utils::print_const_expr`
// for further details.
// @has hide_complex_unevaluated_consts/trait.Container.html
pub trait Container {
// A helper constant that prevents const expressions containing it
// from getting fully evaluated since it doesn't have a body and
// thus is non-reducible. This allows us to specifically test the
// pretty-printing of *unevaluated* consts.
const ABSTRACT: i32;
// Ensure that the private field does not get leaked:
//
// @has - '//*[@id="associatedconstant.STRUCT0"]' \
// 'const STRUCT0: Struct = _'
const STRUCT0: Struct = Struct { private: () };
// @has - '//*[@id="associatedconstant.STRUCT1"]' \
// 'const STRUCT1: (Struct,) = _'
const STRUCT1: (Struct,) = (Struct{private: /**/()},);
// Although the struct field is public here, check that it is not
// displayed. In a future version of rustdoc, we definitely want to
// show it. However for the time being, the printing logic is a bit
// conservative.
//
// @has - '//*[@id="associatedconstant.STRUCT2"]' \
// 'const STRUCT2: Record = _'
const STRUCT2: Record = Record { public: 5 };
// Test that we do not show the incredibly verbose match expr:
//
// @has - '//*[@id="associatedconstant.MATCH0"]' \
// 'const MATCH0: i32 = _'
const MATCH0: i32 = match 234 {
0 => 1,
_ => Self::ABSTRACT,
};
// @has - '//*[@id="associatedconstant.MATCH1"]' \
// 'const MATCH1: bool = _'
const MATCH1: bool = match Self::ABSTRACT {
_ => true,
};
// Check that we hide complex (arithmetic) operations.
// In this case, it is a bit unfortunate since the expression
// is not *that* verbose and it might be quite useful to the reader.
//
// However in general, the expression might be quite large and
// contain match expressions and structs with private fields.
// We would need to recurse over the whole expression and even more
// importantly respect operator precedence when pretty-printing
// the potentially partially censored expression.
// For now, the implementation is quite simple and the choices
// rather conservative.
//
// @has - '//*[@id="associatedconstant.ARITH_OPS"]' \
// 'const ARITH_OPS: i32 = _'
const ARITH_OPS: i32 = Self::ABSTRACT * 2 + 1;
}
pub struct Struct { private: () }
pub struct Record { pub public: i32 }