From bc406bfdd6c579794387494094e19e0361c59ad4 Mon Sep 17 00:00:00 2001
From: Martin Habovstiak <martin.habovstiak@gmail.com>
Date: Fri, 9 Apr 2021 17:58:35 +0200
Subject: [PATCH] Use &mut dyn fmt::Write instead of bool

This replaces manually-written dynamic dispatch with `&mut dyn
fmt::Write` which is hopefully more readable.
---
 src/util/address.rs | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/src/util/address.rs b/src/util/address.rs
index 896a4fb3..dd664d6a 100644
--- a/src/util/address.rs
+++ b/src/util/address.rs
@@ -393,9 +393,14 @@ impl fmt::Display for Address {
                     Network::Testnet | Network::Signet => "tb",
                     Network::Regtest => "bcrt",
                 };
-                let is_alternate = fmt.alternate();
-                let mut opt_up_writer = OptionallyUpperWriter(fmt, is_alternate);
-                let mut bech32_writer = bech32::Bech32Writer::new(hrp, &mut opt_up_writer)?;
+                let mut upper_writer;
+                let writer = if fmt.alternate() {
+                    upper_writer = UpperWriter(fmt);
+                    &mut upper_writer as &mut dyn fmt::Write
+                } else {
+                    fmt as &mut dyn fmt::Write
+                };
+                let mut bech32_writer = bech32::Bech32Writer::new(hrp, writer)?;
                 bech32::WriteBase32::write_u5(&mut bech32_writer, ver)?;
                 bech32::ToBase32::write_base32(&prog, &mut bech32_writer)
             }
@@ -403,16 +408,12 @@ impl fmt::Display for Address {
     }
 }
 
-struct OptionallyUpperWriter<W: fmt::Write>(W, bool);
+struct UpperWriter<W: fmt::Write>(W);
 
-impl<W: fmt::Write> fmt::Write for OptionallyUpperWriter<W> {
+impl<W: fmt::Write> fmt::Write for UpperWriter<W> {
     fn write_str(&mut self, s: &str) -> fmt::Result {
-        if self.1 {
-            for c in s.chars() {
-                self.0.write_char(c.to_ascii_uppercase())?;
-            }
-        } else {
-            self.0.write_str(s)?;
+        for c in s.chars() {
+            self.0.write_char(c.to_ascii_uppercase())?;
         }
         Ok(())
     }