Struct boa_engine::error::JsNativeError

pub struct JsNativeError {
    pub kind: JsNativeErrorKind,
    /* private fields */
}

Native representation of an ideal Error object from Javascript.

This representation is more space efficient than its JsObject equivalent, since it doesn’t need to create a whole new JsObject to be instantiated. Prefer using this over JsError when you don’t need to throw plain JsValues as errors, or when you need to inspect the error type of a JsError.

Examples

let native_error = JsNativeError::uri().with_message("cannot decode uri");

match native_error.kind {
    JsNativeErrorKind::Uri => { /* handle URI error*/ }
    _ => unreachable!(),
}

assert_eq!(native_error.message(), "cannot decode uri");

Fields

kind: JsNativeErrorKind

The kind of native error (e.g. TypeError, SyntaxError, etc.)

Implementations

impl JsNativeError

pub fn aggregate(errors: Vec<JsError>) -> Self

Creates a new JsNativeError of kind AggregateError from a list of JsErrors, with empty message and undefined cause.

Examples

let inner_errors = vec![
    JsNativeError::typ().into(),
    JsNativeError::syntax().into()
];
let error = JsNativeError::aggregate(inner_errors);

assert!(matches!(
    error.kind,
    JsNativeErrorKind::Aggregate(ref errors) if errors.len() == 2
));

pub const fn is_aggregate(&self) -> bool

Check if it’s a JsNativeErrorKind::Aggregate.

pub fn error() -> Self

Creates a new JsNativeError of kind Error, with empty message and undefined cause.

Examples

let error = JsNativeError::error();

assert!(matches!(error.kind, JsNativeErrorKind::Error));

pub const fn is_error(&self) -> bool

Check if it’s a JsNativeErrorKind::Error.

pub fn eval() -> Self

Creates a new JsNativeError of kind EvalError, with empty message and undefined cause.

Examples

let error = JsNativeError::eval();

assert!(matches!(error.kind, JsNativeErrorKind::Eval));

pub const fn is_eval(&self) -> bool

Check if it’s a JsNativeErrorKind::Eval.

pub fn range() -> Self

Creates a new JsNativeError of kind RangeError, with empty message and undefined cause.

Examples

let error = JsNativeError::range();

assert!(matches!(error.kind, JsNativeErrorKind::Range));

pub const fn is_range(&self) -> bool

Check if it’s a JsNativeErrorKind::Range.

pub fn reference() -> Self

Creates a new JsNativeError of kind ReferenceError, with empty message and undefined cause.

Examples

let error = JsNativeError::reference();

assert!(matches!(error.kind, JsNativeErrorKind::Reference));

pub const fn is_reference(&self) -> bool

Check if it’s a JsNativeErrorKind::Reference.

pub fn syntax() -> Self

Creates a new JsNativeError of kind SyntaxError, with empty message and undefined cause.

Examples

let error = JsNativeError::syntax();

assert!(matches!(error.kind, JsNativeErrorKind::Syntax));

pub const fn is_syntax(&self) -> bool

Check if it’s a JsNativeErrorKind::Syntax.

pub fn typ() -> Self

Creates a new JsNativeError of kind TypeError, with empty message and undefined cause.

Examples

let error = JsNativeError::typ();

assert!(matches!(error.kind, JsNativeErrorKind::Type));

pub const fn is_type(&self) -> bool

Check if it’s a JsNativeErrorKind::Type.

pub fn uri() -> Self

Creates a new JsNativeError of kind UriError, with empty message and undefined cause.

Examples

let error = JsNativeError::uri();

assert!(matches!(error.kind, JsNativeErrorKind::Uri));

pub const fn is_uri(&self) -> bool

Check if it’s a JsNativeErrorKind::Uri.

pub fn runtime_limit() -> Self

Creates a new JsNativeError that indicates that the context exceeded the runtime limits.

pub const fn is_runtime_limit(&self) -> bool

Check if it’s a JsNativeErrorKind::RuntimeLimit.

pub fn with_message<S>(self, message: S) -> Self

where S: Into<Box<str>>,

Sets the message of this error.

Examples

let error = JsNativeError::range().with_message("number too large");

assert_eq!(error.message(), "number too large");

pub fn with_cause<V>(self, cause: V) -> Self

where V: Into<JsError>,

Sets the cause of this error.

Examples

let cause = JsNativeError::syntax();
let error = JsNativeError::error().with_cause(cause);

assert!(error.cause().unwrap().as_native().is_some());

pub const fn message(&self) -> &str

Gets the message of this error.

This is equivalent to the NativeError.prototype.message property.

Examples

let error = JsNativeError::range().with_message("number too large");

assert_eq!(error.message(), "number too large");

pub fn cause(&self) -> Option<&JsError>

Gets the cause of this error.

This is equivalent to the NativeError.prototype.cause property.

Examples

let cause = JsNativeError::syntax();
let error = JsNativeError::error().with_cause(cause);

assert!(error.cause().unwrap().as_native().is_some());

pub fn to_opaque(&self, context: &mut Context) -> JsObject

Converts this native error to its opaque representation as a JsObject.

Examples

let context = &mut Context::default();

let error = JsNativeError::error().with_message("error!");
let error_obj = error.to_opaque(context);

assert!(error_obj.is::<ErrorObject>());
assert_eq!(
    error_obj.get(js_string!("message"), context).unwrap(),
    js_string!("error!").into()
)

Panics

If converting a JsNativeErrorKind::RuntimeLimit to an opaque object.

Trait Implementations

impl Clone for JsNativeError

fn clone(&self) -> JsNativeError

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for JsNativeError

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

Formats the value using the given formatter.

impl Display for JsNativeError

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

Formats the value using the given formatter.

impl Error for JsNativeError

fn source(&self) -> Option<&(dyn Error + 'static)>

The lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type based access to context intended for error reports.

impl Finalize for JsNativeError

fn finalize(&self)

Cleanup logic for a type.

impl From<Error> for JsNativeError

fn from(err: Error) -> Self

Converts to this type from the input type.

impl From<JsNativeError> for JsError

fn from(error: JsNativeError) -> Self

Converts to this type from the input type.

impl PartialEq for JsNativeError

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

This method tests for self and other values to be equal, and is used by ==.

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.

impl Trace for JsNativeError

unsafe fn trace(&self, tracer: &mut Tracer)

Marks all contained Gcs.

unsafe fn trace_non_roots(&self)

Trace handles located in GC heap, and mark them as non root.

fn run_finalizer(&self)

Runs Finalize::finalize on this object and all contained subobjects.

impl Eq for JsNativeError

impl StructuralPartialEq for JsNativeError