pub enum LintExpectationId {
    Unstable {
        attr_id: AttrId,
        lint_index: Option<u16>,
    },
    Stable {
        hir_id: HirId,
        attr_index: u16,
        lint_index: Option<u16>,
        attr_id: Option<AttrId>,
    },
}
Expand description

Each lint expectation has a LintExpectationId assigned by the LintLevelsBuilder. Expected Diagnostics get the lint level Expect which stores the LintExpectationId to match it with the actual expectation later on.

The LintExpectationId has to be stable between compilations, as diagnostic instances might be loaded from cache. Lint messages can be emitted during an EarlyLintPass operating on the AST and during a LateLintPass traversing the HIR tree. The AST doesn’t have enough information to create a stable id. The LintExpectationId will instead store the AttrId defining the expectation. These LintExpectationId will be updated to use the stable HirId once the AST has been lowered. The transformation is done by the LintLevelsBuilder

Each lint inside the expect attribute is tracked individually, the lint_index identifies the lint inside the attribute and ensures that the IDs are unique.

The index values have a type of u16 to reduce the size of the LintExpectationId. It’s reasonable to assume that no user will define 2^16 attributes on one node or have that amount of lints listed. u16 values should therefore suffice.

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Unstable

Fields

§attr_id: AttrId
§lint_index: Option<u16>

Used for lints emitted during the EarlyLintPass. This id is not hash stable and should not be cached.

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Stable

Fields

§hir_id: HirId
§attr_index: u16
§lint_index: Option<u16>
§attr_id: Option<AttrId>

The HirId that the lint expectation is attached to. This id is stable and can be cached. The additional index ensures that nodes with several expectations can correctly match diagnostics to the individual expectation.

Implementations§

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impl LintExpectationId

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pub fn is_stable(&self) -> bool

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pub fn get_lint_index(&self) -> Option<u16>

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pub fn set_lint_index(&mut self, new_lint_index: Option<u16>)

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pub fn normalize(self) -> Self

Prepares the id for hashing. Removes references to the ast. Should only be called when the id is stable.

Trait Implementations§

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impl Clone for LintExpectationId

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fn clone(&self) -> LintExpectationId

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for LintExpectationId

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl<__D: Decoder> Decodable<__D> for LintExpectationId

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fn decode(__decoder: &mut __D) -> Self

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impl<__E: Encoder> Encodable<__E> for LintExpectationId

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fn encode(&self, __encoder: &mut __E)

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impl Hash for LintExpectationId

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fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)where
H: Hasher,
Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl<HCX: HashStableContext> HashStable<HCX> for LintExpectationId

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fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

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impl Ord for LintExpectationId

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fn cmp(&self, other: &LintExpectationId) -> Ordering

This method returns an Ordering between self and other. Read more
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fn max(self, other: Self) -> Selfwhere
Self: Sized,

Compares and returns the maximum of two values. Read more
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fn min(self, other: Self) -> Selfwhere
Self: Sized,

Compares and returns the minimum of two values. Read more
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fn clamp(self, min: Self, max: Self) -> Selfwhere
Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval. Read more
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impl PartialEq<LintExpectationId> for LintExpectationId

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fn eq(&self, other: &LintExpectationId) -> bool

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl PartialOrd<LintExpectationId> for LintExpectationId

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fn partial_cmp(&self, other: &LintExpectationId) -> Option<Ordering>

This method returns an ordering between self and other values if one exists. Read more
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fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator. Read more
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fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
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fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator. Read more
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fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more
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impl<HCX: HashStableContext> ToStableHashKey<HCX> for LintExpectationId

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type KeyType = (HirId, u16, u16)

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fn to_stable_hash_key(&self, _: &HCX) -> Self::KeyType

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impl Copy for LintExpectationId

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impl Eq for LintExpectationId

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impl StructuralEq for LintExpectationId

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impl StructuralPartialEq for LintExpectationId

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for Twhere
T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for Twhere
T: ?Sized,

const: unstable · source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for Twhere
T: ?Sized,

const: unstable · source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

const: unstable · source§

fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for Twhere
U: From<T>,

const: unstable · source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for Twhere
T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for Twhere
U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
const: unstable · source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for Twhere
U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
const: unstable · source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.

Layout§

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.

Size: 20 bytes

Size for each variant:

  • Unstable: 10 bytes
  • Stable: 18 bytes