From a8594400927c7363d24625ea1521b89c344ec03d Mon Sep 17 00:00:00 2001
From: Mark Rousskov <mark.simulacrum@gmail.com>
Date: Thu, 6 Jun 2019 16:49:51 -0600
Subject: [PATCH] Shift padding out of suggestions for format strings

---
 src/libsyntax_ext/format.rs         |  8 ++++----
 src/libsyntax_ext/format_foreign.rs | 12 ++++++------
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/src/libsyntax_ext/format.rs b/src/libsyntax_ext/format.rs
index 2863daa13a9..1fdc2e6274a 100644
--- a/src/libsyntax_ext/format.rs
+++ b/src/libsyntax_ext/format.rs
@@ -1043,7 +1043,9 @@ pub fn expand_preparsed_format_args(ecx: &mut ExtCtxt<'_>,
                     let mut show_doc_note = false;
 
                     let mut suggestions = vec![];
-                    for sub in foreign::$kind::iter_subs(fmt_str) {
+                    // account for `"` and account for raw strings `r#`
+                    let padding = str_style.map(|i| i + 2).unwrap_or(1);
+                    for sub in foreign::$kind::iter_subs(fmt_str, padding) {
                         let trn = match sub.translate() {
                             Some(trn) => trn,
 
@@ -1064,9 +1066,7 @@ pub fn expand_preparsed_format_args(ecx: &mut ExtCtxt<'_>,
                         }
 
                         if let Some((start, end)) = pos {
-                            // account for `"` and account for raw strings `r#`
-                            let padding = str_style.map(|i| i + 2).unwrap_or(1);
-                            let sp = fmt_sp.from_inner_byte_pos(start + padding, end + padding);
+                            let sp = fmt_sp.from_inner_byte_pos(start, end);
                             suggestions.push((sp, trn));
                         } else {
                             diag.help(&format!("`{}` should be written as `{}`", sub, trn));
diff --git a/src/libsyntax_ext/format_foreign.rs b/src/libsyntax_ext/format_foreign.rs
index 261b2f373ce..b279dbced84 100644
--- a/src/libsyntax_ext/format_foreign.rs
+++ b/src/libsyntax_ext/format_foreign.rs
@@ -263,10 +263,10 @@ pub mod printf {
     }
 
     /// Returns an iterator over all substitutions in a given string.
-    pub fn iter_subs(s: &str) -> Substitutions<'_> {
+    pub fn iter_subs(s: &str, start_pos: usize) -> Substitutions<'_> {
         Substitutions {
             s,
-            pos: 0,
+            pos: start_pos,
         }
     }
 
@@ -711,7 +711,7 @@ pub mod printf {
         #[test]
         fn test_iter() {
             let s = "The %d'th word %% is: `%.*s` %!\n";
-            let subs: Vec<_> = iter_subs(s).map(|sub| sub.translate()).collect();
+            let subs: Vec<_> = iter_subs(s, 0).map(|sub| sub.translate()).collect();
             assert_eq!(
                 subs.iter().map(|ms| ms.as_ref().map(|s| &s[..])).collect::<Vec<_>>(),
                 vec![Some("{}"), None, Some("{:.*}"), None]
@@ -804,10 +804,10 @@ pub mod shell {
     }
 
     /// Returns an iterator over all substitutions in a given string.
-    pub fn iter_subs(s: &str) -> Substitutions<'_> {
+    pub fn iter_subs(s: &str, start_pos: usize) -> Substitutions<'_> {
         Substitutions {
             s,
-            pos: 0,
+            pos: start_pos,
         }
     }
 
@@ -940,7 +940,7 @@ pub mod shell {
         fn test_iter() {
             use super::iter_subs;
             let s = "The $0'th word $$ is: `$WORD` $!\n";
-            let subs: Vec<_> = iter_subs(s).map(|sub| sub.translate()).collect();
+            let subs: Vec<_> = iter_subs(s, 0).map(|sub| sub.translate()).collect();
             assert_eq!(
                 subs.iter().map(|ms| ms.as_ref().map(|s| &s[..])).collect::<Vec<_>>(),
                 vec![Some("{0}"), None, Some("{WORD}")]