From a78da55db01a6982bd869b4713bb84aee23fb6be Mon Sep 17 00:00:00 2001
From: Pascal Seitz <pascal.seitz@gmail.com>
Date: Tue, 3 May 2022 00:36:24 +0800
Subject: [PATCH] don't break on consecutive punctuations

---
 src/string.rs              | 14 ++++++++++----
 tests/source/issue-5260.rs |  4 ++++
 tests/target/issue-5260.rs |  6 ++++++
 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/src/string.rs b/src/string.rs
index 78b72a50cb2..305ababa58a 100644
--- a/src/string.rs
+++ b/src/string.rs
@@ -343,15 +343,21 @@ fn is_valid_linebreak(input: &[&str], pos: usize) -> bool {
         return true;
     }
     let is_punctuation = is_punctuation(input[pos]);
-    if is_punctuation && !is_part_of_type(input, pos) {
+    if is_punctuation && !is_double_punctuation(input, pos) {
         return true;
     }
     false
 }
 
-fn is_part_of_type(input: &[&str], pos: usize) -> bool {
-    input.get(pos..=pos + 1) == Some(&[":", ":"])
-        || input.get(pos.saturating_sub(1)..=pos) == Some(&[":", ":"])
+fn is_double_punctuation(input: &[&str], pos: usize) -> bool {
+    input
+        .get(pos..=pos + 1)
+        .map(|slice| slice.iter().all(|cha| is_punctuation(cha)))
+        .unwrap_or(false)
+        || input
+            .get(pos.saturating_sub(1)..=pos)
+            .map(|slice| slice.iter().all(|cha| is_punctuation(cha)))
+            .unwrap_or(false)
 }
 
 fn is_new_line(grapheme: &str) -> bool {
diff --git a/tests/source/issue-5260.rs b/tests/source/issue-5260.rs
index c0606817290..5b1647b079e 100644
--- a/tests/source/issue-5260.rs
+++ b/tests/source/issue-5260.rs
@@ -12,3 +12,7 @@ fn documented_with_verylongtype() {
     // on the type when `wrap_comments = true`
 }
 
+/// So many stars ************************************************************************
+fn documented_with_many_stars() {
+    // # don't break consecutive punctuations
+}
diff --git a/tests/target/issue-5260.rs b/tests/target/issue-5260.rs
index 171f6fa51b7..1c1521dcb0d 100644
--- a/tests/target/issue-5260.rs
+++ b/tests/target/issue-5260.rs
@@ -11,3 +11,9 @@ fn documented_with_verylongtype() {
     // # We're using a long type link, rustfmt should not break line
     // on the type when `wrap_comments = true`
 }
+
+/// So many stars
+/// ************************************************************************
+fn documented_with_many_stars() {
+    // # don't break consecutive punctuations
+}