rust/clippy_utils/src/ptr.rs

58 lines
1.8 KiB
Rust

use crate::source::snippet;
use crate::visitors::expr_visitor_no_bodies;
use crate::{path_to_local_id, strip_pat_refs};
use rustc_hir::intravisit::Visitor;
use rustc_hir::{Body, BodyId, ExprKind, HirId, PatKind};
use rustc_lint::LateContext;
use rustc_span::Span;
use std::borrow::Cow;
pub fn get_spans(
cx: &LateContext<'_>,
opt_body_id: Option<BodyId>,
idx: usize,
replacements: &[(&'static str, &'static str)],
) -> Option<Vec<(Span, Cow<'static, str>)>> {
if let Some(body) = opt_body_id.map(|id| cx.tcx.hir().body(id)) {
if let PatKind::Binding(_, binding_id, _, _) = strip_pat_refs(body.params[idx].pat).kind {
extract_clone_suggestions(cx, binding_id, replacements, body)
} else {
Some(vec![])
}
} else {
Some(vec![])
}
}
fn extract_clone_suggestions<'tcx>(
cx: &LateContext<'tcx>,
id: HirId,
replace: &[(&'static str, &'static str)],
body: &'tcx Body<'_>,
) -> Option<Vec<(Span, Cow<'static, str>)>> {
let mut abort = false;
let mut spans = Vec::new();
expr_visitor_no_bodies(|expr| {
if abort {
return false;
}
if let ExprKind::MethodCall(seg, recv, [], _) = expr.kind {
if path_to_local_id(recv, id) {
if seg.ident.name.as_str() == "capacity" {
abort = true;
return false;
}
for &(fn_name, suffix) in replace {
if seg.ident.name.as_str() == fn_name {
spans.push((expr.span, snippet(cx, recv.span, "_") + suffix));
return false;
}
}
}
}
!abort
})
.visit_body(body);
if abort { None } else { Some(spans) }
}