Auto merge of #6664 - camsteffen:path-to-res, r=Manishearth

Remove Option from `path_to_res` return type

changelog: none

Tiny cleanup for `path_to_res` to return `Res` instead of `Option<Res>`.
This commit is contained in:
bors 2021-02-02 16:56:39 +00:00
commit 9fd4f3ea8f
2 changed files with 18 additions and 16 deletions

View File

@ -760,7 +760,7 @@ impl<'tcx> LateLintPass<'tcx> for MatchTypeOnDiagItem {
// Extract the path to the matched type
if let Some(segments) = path_to_matched_type(cx, ty_path);
let segments: Vec<&str> = segments.iter().map(|sym| &**sym).collect();
if let Some(ty_did) = path_to_res(cx, &segments[..]).and_then(|res| res.opt_def_id());
if let Some(ty_did) = path_to_res(cx, &segments[..]).opt_def_id();
// Check if the matched type is a diagnostic item
let diag_items = cx.tcx.diagnostic_items(ty_did.krate);
if let Some(item_name) = diag_items.iter().find_map(|(k, v)| if *v == ty_did { Some(k) } else { None });
@ -833,7 +833,7 @@ fn path_to_matched_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<Ve
// This is not a complete resolver for paths. It works on all the paths currently used in the paths
// module. That's all it does and all it needs to do.
pub fn check_path(cx: &LateContext<'_>, path: &[&str]) -> bool {
if path_to_res(cx, path).is_some() {
if path_to_res(cx, path) != Res::Err {
return true;
}
@ -906,7 +906,7 @@ impl<'tcx> LateLintPass<'tcx> for InterningDefinedSymbol {
}
for &module in &[&paths::KW_MODULE, &paths::SYM_MODULE] {
if let Some(Res::Def(_, def_id)) = path_to_res(cx, module) {
if let Some(def_id) = path_to_res(cx, module).opt_def_id() {
for item in cx.tcx.item_children(def_id).iter() {
if_chain! {
if let Res::Def(DefKind::Const, item_def_id) = item.res;

View File

@ -309,7 +309,15 @@ pub fn match_path_ast(path: &ast::Path, segments: &[&str]) -> bool {
/// Gets the definition associated to a path.
#[allow(clippy::shadow_unrelated)] // false positive #6563
pub fn path_to_res(cx: &LateContext<'_>, path: &[&str]) -> Option<Res> {
pub fn path_to_res(cx: &LateContext<'_>, path: &[&str]) -> Res {
macro_rules! try_res {
($e:expr) => {
match $e {
Some(e) => e,
None => return Res::Err,
}
};
}
fn item_child_by_name<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, name: &str) -> Option<&'tcx Export<HirId>> {
tcx.item_children(def_id)
.iter()
@ -318,12 +326,12 @@ pub fn path_to_res(cx: &LateContext<'_>, path: &[&str]) -> Option<Res> {
let (krate, first, path) = match *path {
[krate, first, ref path @ ..] => (krate, first, path),
_ => return None,
_ => return Res::Err,
};
let tcx = cx.tcx;
let crates = tcx.crates();
let krate = crates.iter().find(|&&num| tcx.crate_name(num).as_str() == krate)?;
let first = item_child_by_name(tcx, krate.as_def_id(), first)?;
let krate = try_res!(crates.iter().find(|&&num| tcx.crate_name(num).as_str() == krate));
let first = try_res!(item_child_by_name(tcx, krate.as_def_id(), first));
let last = path
.iter()
.copied()
@ -343,21 +351,15 @@ pub fn path_to_res(cx: &LateContext<'_>, path: &[&str]) -> Option<Res> {
} else {
None
}
})?;
Some(last.res)
});
try_res!(last).res
}
/// Convenience function to get the `DefId` of a trait by path.
/// It could be a trait or trait alias.
pub fn get_trait_def_id(cx: &LateContext<'_>, path: &[&str]) -> Option<DefId> {
let res = match path_to_res(cx, path) {
Some(res) => res,
None => return None,
};
match res {
match path_to_res(cx, path) {
Res::Def(DefKind::Trait | DefKind::TraitAlias, trait_id) => Some(trait_id),
Res::Err => unreachable!("this trait resolution is impossible: {:?}", &path),
_ => None,
}
}