114 lines
3.9 KiB
Rust
114 lines
3.9 KiB
Rust
//! Detecting diagnostic items.
|
|
//!
|
|
//! Diagnostic items are items that are not language-inherent, but can reasonably be expected to
|
|
//! exist for diagnostic purposes. This allows diagnostic authors to refer to specific items
|
|
//! directly, without having to guess module paths and crates.
|
|
//! Examples are:
|
|
//!
|
|
//! * Traits like `Debug`, that have no bearing on language semantics
|
|
//!
|
|
//! * Compiler internal types like `Ty` and `TyCtxt`
|
|
|
|
use rustc_ast as ast;
|
|
use rustc_hir::diagnostic_items::DiagnosticItems;
|
|
use rustc_middle::ty::query::Providers;
|
|
use rustc_middle::ty::TyCtxt;
|
|
use rustc_span::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
|
|
use rustc_span::symbol::{sym, Symbol};
|
|
|
|
fn observe_item<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
diagnostic_items: &mut DiagnosticItems,
|
|
def_id: LocalDefId,
|
|
) {
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
|
|
let attrs = tcx.hir().attrs(hir_id);
|
|
if let Some(name) = extract(attrs) {
|
|
// insert into our table
|
|
collect_item(tcx, diagnostic_items, name, def_id.to_def_id());
|
|
}
|
|
}
|
|
|
|
fn collect_item(tcx: TyCtxt<'_>, items: &mut DiagnosticItems, name: Symbol, item_def_id: DefId) {
|
|
items.id_to_name.insert(item_def_id, name);
|
|
if let Some(original_def_id) = items.name_to_id.insert(name, item_def_id) {
|
|
if original_def_id != item_def_id {
|
|
let mut err = match tcx.hir().span_if_local(item_def_id) {
|
|
Some(span) => tcx
|
|
.sess
|
|
.struct_span_err(span, &format!("duplicate diagnostic item found: `{name}`.")),
|
|
None => tcx.sess.struct_err(&format!(
|
|
"duplicate diagnostic item in crate `{}`: `{}`.",
|
|
tcx.crate_name(item_def_id.krate),
|
|
name
|
|
)),
|
|
};
|
|
if let Some(span) = tcx.hir().span_if_local(original_def_id) {
|
|
err.span_note(span, "the diagnostic item is first defined here");
|
|
} else {
|
|
err.note(&format!(
|
|
"the diagnostic item is first defined in crate `{}`.",
|
|
tcx.crate_name(original_def_id.krate)
|
|
));
|
|
}
|
|
err.emit();
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Extract the first `rustc_diagnostic_item = "$name"` out of a list of attributes.
|
|
fn extract(attrs: &[ast::Attribute]) -> Option<Symbol> {
|
|
attrs.iter().find_map(|attr| {
|
|
if attr.has_name(sym::rustc_diagnostic_item) { attr.value_str() } else { None }
|
|
})
|
|
}
|
|
|
|
/// Traverse and collect the diagnostic items in the current
|
|
fn diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> DiagnosticItems {
|
|
assert_eq!(cnum, LOCAL_CRATE);
|
|
|
|
// Initialize the collector.
|
|
let mut diagnostic_items = DiagnosticItems::default();
|
|
|
|
// Collect diagnostic items in this crate.
|
|
let crate_items = tcx.hir_crate_items(());
|
|
|
|
for id in crate_items.items() {
|
|
observe_item(tcx, &mut diagnostic_items, id.def_id);
|
|
}
|
|
|
|
for id in crate_items.trait_items() {
|
|
observe_item(tcx, &mut diagnostic_items, id.def_id);
|
|
}
|
|
|
|
for id in crate_items.impl_items() {
|
|
observe_item(tcx, &mut diagnostic_items, id.def_id);
|
|
}
|
|
|
|
for id in crate_items.foreign_items() {
|
|
observe_item(tcx, &mut diagnostic_items, id.def_id);
|
|
}
|
|
|
|
diagnostic_items
|
|
}
|
|
|
|
/// Traverse and collect all the diagnostic items in all crates.
|
|
fn all_diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> DiagnosticItems {
|
|
// Initialize the collector.
|
|
let mut items = DiagnosticItems::default();
|
|
|
|
// Collect diagnostic items in other crates.
|
|
for &cnum in tcx.crates(()).iter().chain(std::iter::once(&LOCAL_CRATE)) {
|
|
for (&name, &def_id) in &tcx.diagnostic_items(cnum).name_to_id {
|
|
collect_item(tcx, &mut items, name, def_id);
|
|
}
|
|
}
|
|
|
|
items
|
|
}
|
|
|
|
pub fn provide(providers: &mut Providers) {
|
|
providers.diagnostic_items = diagnostic_items;
|
|
providers.all_diagnostic_items = all_diagnostic_items;
|
|
}
|