From 0291331203e741b43eda016f8669f5dcdc807ed3 Mon Sep 17 00:00:00 2001
From: David Wood <devel@dtwood.uk>
Date: Sun, 24 Dec 2017 12:27:07 +0000
Subject: [PATCH] Add documentation to expr::SPECIAL_MACRO_WHITELIST

---
 src/expr.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/expr.rs b/src/expr.rs
index 2d4b731a69d7..0c60ba5a201c 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -1811,6 +1811,12 @@ fn rewrite_string_lit(context: &RewriteContext, span: Span, shape: Shape) -> Opt
     )
 }
 
+/// A list of `format!`-like macros, that take a long format string and a list of arguments to
+/// format.
+///
+/// Organized as a list of `(&str, usize)` tuples, giving the name of the macro and the number of
+/// arguments before the format string (none for `format!("format", ...)`, one for `assert!(result,
+/// "format", ...)`, two for `assert_eq!(left, right, "format", ...)`).
 const SPECIAL_MACRO_WHITELIST: &[(&str, usize)] = &[
     // format! like macros
     // From the Rust Standard Library.