From 476992a15d4e01071ac57cec7c8e54b36e606d46 Mon Sep 17 00:00:00 2001
From: Seiichi Uchida <seuchida@gmail.com>
Date: Sun, 14 Oct 2018 21:43:35 +0900
Subject: [PATCH 1/3] Add a test for #3092

---
 tests/source/trait.rs |  9 +++++++++
 tests/target/trait.rs | 12 ++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/tests/source/trait.rs b/tests/source/trait.rs
index 2fa25d0802cf..d5ee4f044173 100644
--- a/tests/source/trait.rs
+++ b/tests/source/trait.rs
@@ -106,3 +106,12 @@ trait Foo<'a> {
 impl<'a> Foo<'a> for i32 {
     type Bar<  'a  > = i32;
 }
+
+// #3092
+pub mod test {
+    pub trait ATraitWithALooongName {}
+    pub trait ATrait
+        :ATraitWithALooongName + ATraitWithALooongName + ATraitWithALooongName + ATraitWithALooongName
+{
+}
+}
diff --git a/tests/target/trait.rs b/tests/target/trait.rs
index 2eb2c12aa305..18747c47fef3 100644
--- a/tests/target/trait.rs
+++ b/tests/target/trait.rs
@@ -144,3 +144,15 @@ trait Foo<'a> {
 impl<'a> Foo<'a> for i32 {
     type Bar<'a> = i32;
 }
+
+// #3092
+pub mod test {
+    pub trait ATraitWithALooongName {}
+    pub trait ATrait:
+        ATraitWithALooongName
+        + ATraitWithALooongName
+        + ATraitWithALooongName
+        + ATraitWithALooongName
+    {
+    }
+}

From fdfb489c48a1996076cede1bc1a417134fef57f2 Mon Sep 17 00:00:00 2001
From: Seiichi Uchida <seuchida@gmail.com>
Date: Sun, 14 Oct 2018 21:43:59 +0900
Subject: [PATCH 2/3] Add a correct indent before trait's closing brace with
 empty body

---
 src/items.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/items.rs b/src/items.rs
index f74458fdaa65..1673bffbce9b 100644
--- a/src/items.rs
+++ b/src/items.rs
@@ -1121,6 +1121,7 @@ pub fn format_trait(context: &RewriteContext, item: &ast::Item, offset: Indent)
 
         let snippet = context.snippet(item.span);
         let open_pos = snippet.find_uncommented("{")? + 1;
+        let outer_indent_str = offset.block_only().to_string_with_newline(context.config);
 
         if !trait_items.is_empty() || contains_comment(&snippet[open_pos..]) {
             let mut visitor = FmtVisitor::from_context(context);
@@ -1134,13 +1135,12 @@ pub fn format_trait(context: &RewriteContext, item: &ast::Item, offset: Indent)
             visitor.format_missing(item.span.hi() - BytePos(1));
 
             let inner_indent_str = visitor.block_indent.to_string_with_newline(context.config);
-            let outer_indent_str = offset.block_only().to_string_with_newline(context.config);
 
             result.push_str(&inner_indent_str);
             result.push_str(visitor.buffer.to_string().trim());
             result.push_str(&outer_indent_str);
         } else if result.contains('\n') {
-            result.push('\n');
+            result.push_str(&outer_indent_str);
         }
 
         result.push('}');

From 5f5d04283ce68b514a13ae5c41ba3961549ab46f Mon Sep 17 00:00:00 2001
From: Seiichi Uchida <seuchida@gmail.com>
Date: Sun, 14 Oct 2018 21:44:56 +0900
Subject: [PATCH 3/3] Use correct width

When rewriting trait bounds on the next line, we do not want to add an extra
indentation. However, the max width should be smaller.
---
 src/expr.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/expr.rs b/src/expr.rs
index 7a6a14730601..8a5b3de7a147 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -1937,7 +1937,9 @@ fn shape_from_rhs_tactic(
     rhs_tactic: RhsTactics,
 ) -> Option<Shape> {
     match rhs_tactic {
-        RhsTactics::ForceNextLineWithoutIndent => Some(shape.with_max_width(context.config)),
+        RhsTactics::ForceNextLineWithoutIndent => shape
+            .with_max_width(context.config)
+            .sub_width(shape.indent.width()),
         RhsTactics::Default => {
             Shape::indented(shape.indent.block_indent(context.config), context.config)
                 .sub_width(shape.rhs_overhead(context.config))