Coverage Report

Created: 2026-07-19 07:55

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/wasm-tools/crates/wasm-encoder/src/component/start.rs
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use crate::{ComponentSection, ComponentSectionId, Encode};
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use alloc::vec::Vec;
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/// An encoder for the start section of WebAssembly components.
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///
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/// # Example
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///
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/// ```
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/// use wasm_encoder::{Component, ComponentStartSection};
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///
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/// let start = ComponentStartSection { function_index: 0, args: [0, 1], results: 1 };
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///
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/// let mut component = Component::new();
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/// component.section(&start);
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///
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/// let bytes = component.finish();
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/// ```
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#[derive(Clone, Debug)]
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pub struct ComponentStartSection<A> {
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    /// The index to the start function.
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    pub function_index: u32,
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    /// The arguments to pass to the start function.
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    ///
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    /// An argument is an index to a value.
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    pub args: A,
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    /// The number of expected results for the start function.
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    ///
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    /// This should match the number of results for the type of
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    /// the function referenced by `function_index`.
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    pub results: u32,
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}
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impl<A> Encode for ComponentStartSection<A>
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where
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    A: AsRef<[u32]>,
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{
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    fn encode(&self, sink: &mut Vec<u8>) {
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        let mut bytes = Vec::new();
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        self.function_index.encode(&mut bytes);
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        self.args.as_ref().encode(&mut bytes);
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        self.results.encode(&mut bytes);
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        bytes.encode(sink);
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    }
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}
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impl<A> ComponentSection for ComponentStartSection<A>
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where
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    A: AsRef<[u32]>,
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{
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0
    fn id(&self) -> u8 {
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0
        ComponentSectionId::Start.into()
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0
    }
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}