use crate::path_to_local_id;
use rustc_hir as hir;
-use rustc_hir::intravisit::{self, walk_expr, NestedVisitorMap, Visitor};
-use rustc_hir::{Arm, Body, Expr, HirId, Stmt};
+use rustc_hir::intravisit::{self, walk_expr, ErasedMap, NestedVisitorMap, Visitor};
+use rustc_hir::{def::Res, Arm, Block, Body, BodyId, Destination, Expr, ExprKind, HirId, Stmt};
use rustc_lint::LateContext;
use rustc_middle::hir::map::Map;
}
fn visit_stmt(&mut self, stmt: &'hir hir::Stmt<'_>) {
- intravisit::walk_stmt(&mut *self.inside_stmt(true), stmt)
+ intravisit::walk_stmt(&mut *self.inside_stmt(true), stmt);
}
fn visit_expr(&mut self, expr: &'hir hir::Expr<'_>) {
NestedVisitorMap::OnlyBodies(self.hir)
}
}
+
+/// A type which can be visited.
+pub trait Visitable<'tcx> {
+ /// Calls the corresponding `visit_*` function on the visitor.
+ fn visit<V: Visitor<'tcx>>(self, visitor: &mut V);
+}
+macro_rules! visitable_ref {
+ ($t:ident, $f:ident) => {
+ impl Visitable<'tcx> for &'tcx $t<'tcx> {
+ fn visit<V: Visitor<'tcx>>(self, visitor: &mut V) {
+ visitor.$f(self);
+ }
+ }
+ };
+}
+visitable_ref!(Block, visit_block);
+
+/// Calls the given function for each break expression.
+pub fn visit_break_exprs<'tcx>(
+ node: impl Visitable<'tcx>,
+ f: impl FnMut(&'tcx Expr<'tcx>, Destination, Option<&'tcx Expr<'tcx>>),
+) {
+ struct V<F>(F);
+ impl<'tcx, F: FnMut(&'tcx Expr<'tcx>, Destination, Option<&'tcx Expr<'tcx>>)> Visitor<'tcx> for V<F> {
+ type Map = ErasedMap<'tcx>;
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::None
+ }
+
+ fn visit_expr(&mut self, e: &'tcx Expr<'_>) {
+ if let ExprKind::Break(dest, sub_expr) = e.kind {
+ self.0(e, dest, sub_expr);
+ }
+ walk_expr(self, e);
+ }
+ }
+
+ node.visit(&mut V(f));
+}
+
+/// Checks if the given resolved path is used in the given body.
+pub fn is_res_used(cx: &LateContext<'_>, res: Res, body: BodyId) -> bool {
+ struct V<'a, 'tcx> {
+ cx: &'a LateContext<'tcx>,
+ res: Res,
+ found: bool,
+ }
+ impl Visitor<'tcx> for V<'_, 'tcx> {
+ type Map = Map<'tcx>;
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
+ }
+
+ fn visit_expr(&mut self, e: &'tcx Expr<'_>) {
+ if self.found {
+ return;
+ }
+
+ if let ExprKind::Path(p) = &e.kind {
+ if self.cx.qpath_res(p, e.hir_id) == self.res {
+ self.found = true;
+ }
+ } else {
+ walk_expr(self, e);
+ }
+ }
+ }
+
+ let mut v = V { cx, res, found: false };
+ v.visit_expr(&cx.tcx.hir().body(body).value);
+ v.found
+}