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a647ba250a
`#[cfg]`s are frequently used to gate crate content behind cargo features. This can lead to very confusing errors when features are missing. For example, `serde` doesn't have the `derive` feature by default. Therefore, `serde::Serialize` fails to resolve with a generic error, even though the macro is present in the docs. This commit adds a list of all stripped item names to metadata. This is filled during macro expansion and then, through a fed query, persisted in metadata. The downstream resolver can then access the metadata to look at possible candidates for mentioning in the errors. This slightly increases metadata (800k->809k for the feature-heavy windows crate), but not enough to really matter.
13 lines
286 B
Rust
13 lines
286 B
Rust
pub mod inner {
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pub fn i_am_here() {
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#[cfg(feature = "another one that doesn't exist")]
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loop {}
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}
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}
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fn main() {
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inner::i_am_here();
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// ensure that nothing bad happens when we are checking for cfgs
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inner::i_am_not(); //~ ERROR cannot find function
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}
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