Grcov report - checked

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//! Checked downcasts of a guest `anyref`. wasmtime's `unwrap_*` accessors

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//! panic on a kind mismatch; a malformed guest value must surface as an error

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//! instead of aborting the host.

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use wasmtime::{AnyRef, ArrayRef, AsContext, I31, Rooted, StructRef};

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pub trait CheckedAnyRef {

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    /// # Errors

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    /// Fails when the reference is unrooted or is not an `i31`.

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    fn checked_i31(&self, store: impl AsContext) -> wasmtime::Result<I31>;

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    /// # Errors

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    /// Fails when the reference is unrooted or is not a struct.

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    fn checked_struct(&self, store: impl AsContext) -> wasmtime::Result<Rooted<StructRef>>;

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    /// # Errors

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    /// Fails when the reference is unrooted or is not an array.

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    fn checked_array(&self, store: impl AsContext) -> wasmtime::Result<Rooted<ArrayRef>>;

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impl CheckedAnyRef for Rooted<AnyRef> {

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    fn checked_i31(&self, store: impl AsContext) -> wasmtime::Result<I31> {

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        self.as_i31(store)?.ok_or_else(|| kind_mismatch("i31"))

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81

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5016

    fn checked_struct(&self, store: impl AsContext) -> wasmtime::Result<Rooted<StructRef>> {

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5016

        self.as_struct(store)?

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5016

            .ok_or_else(|| kind_mismatch("struct"))

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5016

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1184

    fn checked_array(&self, store: impl AsContext) -> wasmtime::Result<Rooted<ArrayRef>> {

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1184

        self.as_array(store)?.ok_or_else(|| kind_mismatch("array"))

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1184

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fn kind_mismatch(expected: &str) -> wasmtime::Error {

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    wasmtime::Error::msg(format!("guest anyref is not the expected {expected} ref"))

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2

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#[cfg(test)]

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mod tests;