Perform another layer of pattern equality checking before spelling th…

…e lint

clippy_lints/src/methods/inspect_then_for_each.rs

@@ -1,23 +1,46 @@
+use if_chain::if_chain;
 use rustc_hir as hir;
 use rustc_lint::LateContext;
 use rustc_span::source_map::Span;
 
-use crate::utils::{match_trait_method, paths, span_lint_and_help};
+use crate::utils::{match_trait_method, paths, span_lint_and_help, SpanlessEq};
 
 use super::INSPECT_THEN_FOR_EACH;
 
 /// lint use of `inspect().for_each()` for `Iterators`
-pub(super) fn lint<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, inspect_span: Span) {
+pub(super) fn lint<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'_>,
+    inspect_args: &'tcx [hir::Expr<'_>],
+    for_each_args: &'tcx [hir::Expr<'_>],
+    inspect_span: Span,
+) {
     if match_trait_method(cx, expr, &paths::ITERATOR) {
-        let msg = "called `inspect(..).for_each(..)` on an `Iterator`";
-        let hint = "move the code from `inspect(..)` to `for_each(..)` and remove the `inspect(..)`";
-        span_lint_and_help(
-            cx,
-            INSPECT_THEN_FOR_EACH,
-            inspect_span.with_hi(expr.span.hi()),
-            msg,
-            None,
-            hint,
-        );
+        let inspect_closure = &inspect_args[1].kind;
+        let for_each_closure = &for_each_args[1].kind;
+
+        if_chain! {
+            if let hir::ExprKind::Closure(_, _, inspect_closure_body_id, _, _) = inspect_closure;
+            if let hir::ExprKind::Closure(_, _, for_each_closure_body_id, _, _) = for_each_closure;
+
+            let inspect_closure_pat = cx.tcx.hir().body(*inspect_closure_body_id).params[0].pat;
+            let for_each_closure_pat = cx.tcx.hir().body(*for_each_closure_body_id).params[0].pat;
+
+            if SpanlessEq::new(cx).eq_pat(inspect_closure_pat, for_each_closure_pat);
+
+            then {
+                let msg = "called `inspect(..).for_each(..)` on an `Iterator`";
+                let hint = "move the code from `inspect(..)` to `for_each(..)` and remove the `inspect(..)`";
+
+                span_lint_and_help(
+                    cx,
+                    INSPECT_THEN_FOR_EACH,
+                    inspect_span.with_hi(expr.span.hi()),
+                    msg,
+                    None,
+                    hint,
+                );
+            }
+        }
     }
 }

clippy_lints/src/methods/mod.rs

@@ -1585,7 +1585,9 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             ["get_or_insert_with", ..] => unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "get_or_insert"),
             ["ok_or_else", ..] => unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "ok_or"),
             ["collect", "map"] => lint_map_collect(cx, expr, arg_lists[1], arg_lists[0]),
-            ["for_each", "inspect"] => inspect_then_for_each::lint(cx, expr, method_spans[1]),
+            ["for_each", "inspect"] => {
+                inspect_then_for_each::lint(cx, expr, arg_lists[1], arg_lists[0], method_spans[1])
+            },
             _ => {},
         }