From 0979545330689186dff27e22f539c1a06887981f Mon Sep 17 00:00:00 2001
From: Andy Russell <arussell123@gmail.com>
Date: Sun, 28 Jun 2020 18:20:06 -0400
Subject: [PATCH] rustdoc: insert newlines between attributes

---
 src/librustdoc/html/render.rs  | 21 +++++++++++++--------
 src/test/rustdoc/attributes.rs |  4 ++--
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 8bba21a2e7a..301896fd2c1 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -42,6 +42,7 @@
 use std::string::ToString;
 use std::sync::Arc;
 
+use itertools::Itertools;
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::flock;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -3170,15 +3171,19 @@ fn item_enum(w: &mut Buffer, cx: &Context, it: &clean::Item, e: &clean::Enum) {
 //     bar: usize,
 // }
 fn render_attributes(w: &mut Buffer, it: &clean::Item, top: bool) {
-    let mut attrs = String::new();
+    let attrs = it
+        .attrs
+        .other_attrs
+        .iter()
+        .filter_map(|attr| {
+            if ALLOWED_ATTRIBUTES.contains(&attr.name_or_empty()) {
+                Some(pprust::attribute_to_string(&attr))
+            } else {
+                None
+            }
+        })
+        .join("\n");
 
-    for attr in &it.attrs.other_attrs {
-        if !ALLOWED_ATTRIBUTES.contains(&attr.name_or_empty()) {
-            continue;
-        }
-
-        attrs.push_str(&pprust::attribute_to_string(&attr));
-    }
     if !attrs.is_empty() {
         write!(
             w,
diff --git a/src/test/rustdoc/attributes.rs b/src/test/rustdoc/attributes.rs
index e9cd3514a07..54c5939f908 100644
--- a/src/test/rustdoc/attributes.rs
+++ b/src/test/rustdoc/attributes.rs
@@ -8,8 +8,8 @@ pub extern "C" fn f() {}
 #[export_name = "bar"]
 pub extern "C" fn g() {}
 
-// @has foo/enum.Foo.html '//*[@class="docblock attributes top-attr"]' '#[repr(i64)]'
-// @has foo/enum.Foo.html '//*[@class="docblock attributes top-attr"]' '#[must_use]'
+// @matches foo/enum.Foo.html '//*[@class="docblock attributes top-attr"]' \
+//      '(?m)\A#\[repr\(i64\)\]\n#\[must_use\]\Z'
 #[repr(i64)]
 #[must_use]
 pub enum Foo {