From 984ac100a4072b7f64898913afa70e71c65c79da Mon Sep 17 00:00:00 2001
From: topecongiro <seuchida@gmail.com>
Date: Fri, 22 Dec 2017 12:00:24 +0900
Subject: [PATCH] Fix indent width bug when recovering comments

Using last_line_width() ignores the width of tab character ('\t').
---
 src/missed_spans.rs       |  7 ++++---
 tests/source/hard-tabs.rs | 11 +++++++++++
 tests/target/hard-tabs.rs | 11 +++++++++++
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/src/missed_spans.rs b/src/missed_spans.rs
index 718ac6bfaab..dff6b94bd75 100644
--- a/src/missed_spans.rs
+++ b/src/missed_spans.rs
@@ -210,21 +210,22 @@ impl<'a> FmtVisitor<'a> {
 
         let fix_indent = last_char.map_or(true, |rev_c| ['{', '\n'].contains(&rev_c));
 
-        if fix_indent {
+        let comment_indent = if fix_indent {
             if let Some('{') = last_char {
                 self.push_str("\n");
             }
             let indent_str = self.block_indent.to_string(self.config);
             self.push_str(&indent_str);
+            self.block_indent
         } else {
             self.push_str(" ");
-        }
+            Indent::from_width(self.config, last_line_width(&self.buffer))
+        };
 
         let comment_width = ::std::cmp::min(
             self.config.comment_width(),
             self.config.max_width() - self.block_indent.width(),
         );
-        let comment_indent = Indent::from_width(self.config, last_line_width(&self.buffer));
         let comment_shape = Shape::legacy(comment_width, comment_indent);
         let comment_str = rewrite_comment(subslice, false, comment_shape, self.config)
             .unwrap_or_else(|| String::from(subslice));
diff --git a/tests/source/hard-tabs.rs b/tests/source/hard-tabs.rs
index f598ad881d0..b8fd09f8792 100644
--- a/tests/source/hard-tabs.rs
+++ b/tests/source/hard-tabs.rs
@@ -72,3 +72,14 @@ fn generic<T>(arg: T) -> &SomeType
         }
     });
 }
+
+// #2296
+impl Foo {
+	// a comment
+	// on multiple lines
+	fn foo() {
+		// another comment
+		// on multiple lines
+		let x = true;
+	}
+}
diff --git a/tests/target/hard-tabs.rs b/tests/target/hard-tabs.rs
index 72d366b1fa1..90be4d6b367 100644
--- a/tests/target/hard-tabs.rs
+++ b/tests/target/hard-tabs.rs
@@ -86,3 +86,14 @@ fn main() {
 		false => (),
 	});
 }
+
+// #2296
+impl Foo {
+	// a comment
+	// on multiple lines
+	fn foo() {
+		// another comment
+		// on multiple lines
+		let x = true;
+	}
+}