From 073010d425d7b6ff5e79fd41f209e4915daa6066 Mon Sep 17 00:00:00 2001
From: Noah Lev <camelidcamel@gmail.com>
Date: Thu, 17 Feb 2022 14:58:46 -0800
Subject: Improve handling of `tmp` variable name conflicts

---
 compiler/rustc_parse/src/parser/diagnostics.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

(limited to 'compiler/rustc_parse/src/parser')

diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index 26ca018685e..dcb150f18aa 100644
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -1325,13 +1325,17 @@ impl<'a> Parser<'a> {
         kind: IncDecRecovery,
         (pre_span, post_span): (Span, Span),
     ) {
+        let mut msg = format!("use `{}= 1` instead", kind.op.chr());
+        if base_src.trim() == "tmp" {
+            msg.push_str(" (rename `tmp` so it doesn't conflict with your variable)");
+        }
         err.multipart_suggestion(
-            &format!("use `{}= 1` instead", kind.op.chr()),
+            &msg,
             vec![
                 (pre_span, "{ let tmp = ".to_string()),
                 (post_span, format!("; {} {}= 1; tmp }}", base_src, kind.op.chr())),
             ],
-            Applicability::MachineApplicable,
+            Applicability::HasPlaceholders,
         );
     }
 
-- 
cgit 1.4.1-3-g733a5