1 use crate::methods::get_hint_if_single_char_arg;
2 use crate::utils::{snippet_with_applicability, span_lint_and_sugg};
3 use rustc_errors::Applicability;
5 use rustc_lint::LateContext;
7 use super::SINGLE_CHAR_ADD_STR;
9 /// lint for length-1 `str`s as argument for `insert_str`
10 pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, args: &[hir::Expr<'_>]) {
11 let mut applicability = Applicability::MachineApplicable;
12 if let Some(extension_string) = get_hint_if_single_char_arg(cx, &args[2], &mut applicability) {
13 let base_string_snippet =
14 snippet_with_applicability(cx, args[0].span.source_callsite(), "_", &mut applicability);
15 let pos_arg = snippet_with_applicability(cx, args[1].span, "..", &mut applicability);
16 let sugg = format!("{}.insert({}, {})", base_string_snippet, pos_arg, extension_string);
21 "calling `insert_str()` using a single-character string literal",
22 "consider using `insert` with a character literal",