Skip to content

Commit

Permalink
Auto merge of rust-lang#13431 - GnomedDev:split-def_path_res, r=y21
Browse files Browse the repository at this point in the history
Split def_path_res into two parts

`def_path_res` previously had two jobs:
1. looking up the crates to find the path in
2. looking up path in said crates

This splits that job up into two functions, keeping `def_path_res` as an adapter between the both, to avoid repeating the first step when repeatedly looking up items in the same crate.

changelog: none
  • Loading branch information
bors committed Sep 23, 2024
2 parents b7ab258 + 6b34c8d commit 8ab744e
Show file tree
Hide file tree
Showing 2 changed files with 34 additions and 21 deletions.
15 changes: 9 additions & 6 deletions clippy_lints/src/regex.rs
Original file line number Diff line number Diff line change
Expand Up @@ -3,7 +3,7 @@ use std::fmt::Display;
use clippy_utils::consts::{ConstEvalCtxt, Constant};
use clippy_utils::diagnostics::{span_lint, span_lint_and_help};
use clippy_utils::source::SpanRangeExt;
use clippy_utils::{def_path_def_ids, path_def_id, paths};
use clippy_utils::{def_path_res_with_base, find_crates, path_def_id, paths};
use rustc_ast::ast::{LitKind, StrStyle};
use rustc_hir::def_id::DefIdMap;
use rustc_hir::{BorrowKind, Expr, ExprKind};
Expand Down Expand Up @@ -75,11 +75,14 @@ impl<'tcx> LateLintPass<'tcx> for Regex {
// We don't use `match_def_path` here because that relies on matching the exact path, which changed
// between regex 1.8 and 1.9
//
// `def_path_def_ids` will resolve through re-exports but is relatively heavy, so we only perform
// the operation once and store the results
let mut resolve = |path, kind| {
for id in def_path_def_ids(cx.tcx, path) {
self.definitions.insert(id, kind);
// `def_path_res_with_base` will resolve through re-exports but is relatively heavy, so we only
// perform the operation once and store the results
let regex_crates = find_crates(cx.tcx, sym!(regex));
let mut resolve = |path: &[&str], kind: RegexKind| {
for res in def_path_res_with_base(cx.tcx, regex_crates.clone(), &path[1..]) {
if let Some(id) = res.opt_def_id() {
self.definitions.insert(id, kind);
}
}
};

Expand Down
40 changes: 25 additions & 15 deletions clippy_utils/src/lib.rs
Original file line number Diff line number Diff line change
Expand Up @@ -671,6 +671,17 @@ fn item_children_by_name(tcx: TyCtxt<'_>, def_id: DefId, name: Symbol) -> Vec<Re
}
}

/// Finds the crates called `name`, may be multiple due to multiple major versions.
pub fn find_crates(tcx: TyCtxt<'_>, name: Symbol) -> Vec<Res> {
tcx.crates(())
.iter()
.copied()
.filter(move |&num| tcx.crate_name(num) == name)
.map(CrateNum::as_def_id)
.map(|id| Res::Def(tcx.def_kind(id), id))
.collect()
}

/// Resolves a def path like `std::vec::Vec`.
///
/// Can return multiple resolutions when there are multiple versions of the same crate, e.g.
Expand All @@ -681,15 +692,7 @@ fn item_children_by_name(tcx: TyCtxt<'_>, def_id: DefId, name: Symbol) -> Vec<Re
///
/// This function is expensive and should be used sparingly.
pub fn def_path_res(tcx: TyCtxt<'_>, path: &[&str]) -> Vec<Res> {
fn find_crates(tcx: TyCtxt<'_>, name: Symbol) -> impl Iterator<Item = DefId> + '_ {
tcx.crates(())
.iter()
.copied()
.filter(move |&num| tcx.crate_name(num) == name)
.map(CrateNum::as_def_id)
}

let (base, mut path) = match *path {
let (base, path) = match *path {
[primitive] => {
return vec![PrimTy::from_name(Symbol::intern(primitive)).map_or(Res::Err, Res::PrimTy)];
},
Expand All @@ -705,18 +708,25 @@ pub fn def_path_res(tcx: TyCtxt<'_>, path: &[&str]) -> Vec<Res> {
None
};

let starts = find_primitive_impls(tcx, base)
.chain(find_crates(tcx, base_sym))
let crates = find_primitive_impls(tcx, base)
.chain(local_crate)
.map(|id| Res::Def(tcx.def_kind(id), id));
.map(|id| Res::Def(tcx.def_kind(id), id))
.chain(find_crates(tcx, base_sym))
.collect();

let mut resolutions: Vec<Res> = starts.collect();
def_path_res_with_base(tcx, crates, path)
}

/// Resolves a def path like `vec::Vec` with the base `std`.
///
/// This is lighter than [`def_path_res`], and should be called with [`find_crates`] looking up
/// items from the same crate repeatedly, although should still be used sparingly.
pub fn def_path_res_with_base(tcx: TyCtxt<'_>, mut base: Vec<Res>, mut path: &[&str]) -> Vec<Res> {
while let [segment, rest @ ..] = path {
path = rest;
let segment = Symbol::intern(segment);

resolutions = resolutions
base = base
.into_iter()
.filter_map(|res| res.opt_def_id())
.flat_map(|def_id| {
Expand All @@ -735,7 +745,7 @@ pub fn def_path_res(tcx: TyCtxt<'_>, path: &[&str]) -> Vec<Res> {
.collect();
}

resolutions
base
}

/// Resolves a def path like `std::vec::Vec` to its [`DefId`]s, see [`def_path_res`].
Expand Down

0 comments on commit 8ab744e

Please sign in to comment.