use crate::utils::SpanlessEq;
-use crate::utils::{get_item_name, higher, match_type, paths, snippet, span_lint_and_then, walk_ptrs_ty};
+use crate::utils::{get_item_name, higher, match_type, paths, snippet, snippet_opt, span_lint_and_then, walk_ptrs_ty};
use if_chain::if_chain;
use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
use rustc::hir::*;
///
/// **Known problems:** Some false negatives, eg.:
/// ```rust
- /// let k = &key;
- /// if !m.contains_key(k) {
- /// m.insert(k.clone(), v);
+ /// # use std::collections::HashMap;
+ /// # let mut map = HashMap::new();
+ /// # let v = 1;
+ /// # let k = 1;
+ /// if !map.contains_key(&k) {
+ /// map.insert(k.clone(), v);
/// }
/// ```
///
/// **Example:**
/// ```rust
- /// if !m.contains_key(&k) {
- /// m.insert(k, v)
+ /// # use std::collections::HashMap;
+ /// # let mut map = HashMap::new();
+ /// # let k = 1;
+ /// # let v = 1;
+ /// if !map.contains_key(&k) {
+ /// map.insert(k, v);
/// }
/// ```
- /// can be rewritten as:
+ /// can both be rewritten as:
/// ```rust
- /// m.entry(k).or_insert(v);
+ /// # use std::collections::HashMap;
+ /// # let mut map = HashMap::new();
+ /// # let k = 1;
+ /// # let v = 1;
+ /// map.entry(k).or_insert(v);
/// ```
pub MAP_ENTRY,
perf,
None
}
-struct InsertVisitor<'a, 'tcx: 'a, 'b> {
+struct InsertVisitor<'a, 'tcx, 'b> {
cx: &'a LateContext<'a, 'tcx>,
span: Span,
ty: &'static str,
if path.ident.name == sym!(insert);
if get_item_name(self.cx, self.map) == get_item_name(self.cx, ¶ms[0]);
if SpanlessEq::new(self.cx).eq_expr(self.key, ¶ms[1]);
+ if snippet_opt(self.cx, self.map.span) == snippet_opt(self.cx, params[0].span);
then {
span_lint_and_then(self.cx, MAP_ENTRY, self.span,
&format!("usage of `contains_key` followed by `insert` on a `{}`", self.ty), |db| {