1 files changed, 20 insertions, 0 deletions
diff --git a/src/tools/rustfmt/tests/source/issue-4577.rs b/src/tools/rustfmt/tests/source/issue-4577.rs
new file mode 100644
index 000000000..79975dd73
--- /dev/null
+++ b/src/tools/rustfmt/tests/source/issue-4577.rs
@@ -0,0 +1,20 @@
+fn main() {
+    let s: String = "ABAABBAA".chars()
+        .filter(|c| {
+            if *c == 'A' {
+                true
+            }
+            else {
+                false
+            }
+        })
+        .map(|c| -> char {
+        if c == 'A' {
+            '0'
+        } else {
+            '1'
+        }
+    }).collect();
+    
+    println!("{}", s);
+}