From 9957dc531d0ffae55460214263d50bd959c3373c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20Th=C3=A4ter?= <ct@pipapo.org>
Date: Sat, 7 Aug 2021 09:32:18 +0200
Subject: [PATCH] Use a 'stderr' feature to target log output to stderr

---
 Cargo.toml |  1 +
 src/lib.rs | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/Cargo.toml b/Cargo.toml
index 214f303..9a0c408 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,7 @@ edition = "2018"
 default = ["colored", "chrono"]
 colors = ["colored"]
 timestamps = ["chrono"]
+stderr = []
 
 [dependencies]
 log = { version = "^0.4.5", features = ["std"] }
diff --git a/src/lib.rs b/src/lib.rs
index 954ad6a..9e4a9ce 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -305,6 +305,7 @@ impl Log for SimpleLogger {
 
             #[cfg(feature = "chrono")]
             if self.timestamps {
+                #[cfg(not(feature = "stderr"))]
                 println!(
                     "{} {:<5} [{}] {}",
                     Local::now().format("%Y-%m-%d %H:%M:%S,%3f"),
@@ -312,10 +313,21 @@ impl Log for SimpleLogger {
                     target,
                     record.args()
                 );
+                #[cfg(feature = "stderr")]
+                eprintln!(
+                    "{} {:<5} [{}] {}",
+                    Local::now().format("%Y-%m-%d %H:%M:%S,%3f"),
+                    level_string,
+                    target,
+                    record.args()
+                );
                 return;
             }
 
+            #[cfg(not(feature = "stderr"))]
             println!("{:<5} [{}] {}", level_string, target, record.args());
+            #[cfg(feature = "stderr")]
+            eprintln!("{:<5} [{}] {}", level_string, target, record.args());
         }
     }