From 70fa092df122b97b1de0cb26e29514445a9390ed Mon Sep 17 00:00:00 2001
From: David Peter <mail@david-peter.de>
Date: Wed, 7 Dec 2022 21:30:10 +0100
Subject: [PATCH] Do not fail if output is not a TTY for `--panels=auto`

closes #184
---
 CHANGELOG.md     | 11 +++++++++++
 src/bin/hexyl.rs | 11 +++++------
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a5a1944..c7c0453 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,14 @@
+# unreleased
+
+## Features
+
+- Only show one panel by default if the terminal width is not wide enough for two panels, see #182 (@sharkdp)
+
+## Bugfixes
+
+- Do not fail with an error if `--panels=auto` is used and the output is piped, see #184 (@sharkdp)
+
+
 # v0.11.0
 
 ## Features
diff --git a/src/bin/hexyl.rs b/src/bin/hexyl.rs
index 3ecf1b0..42d4768 100644
--- a/src/bin/hexyl.rs
+++ b/src/bin/hexyl.rs
@@ -163,7 +163,8 @@ fn run() -> Result<()> {
                 .help(
                     "Sets the number of hex data panels to be displayed. \
                     `--panels=auto` will display the maximum number of hex data panels \
-                    based on the current terminal width",
+                    based on the current terminal width. By default, hexyl will show \
+                    two panels, unless the terminal is not wide enough for that.",
                 ),
         )
         .arg(
@@ -389,12 +390,10 @@ fn run() -> Result<()> {
         1
     };
 
+    let terminal_width = terminal_size().map(|s| s.0 .0 as u64).unwrap_or(80);
+
     let panels = if matches.get_one::<String>("panels").map(String::as_ref) == Some("auto") {
-        max_panels_fn(
-            terminal_size().ok_or_else(|| anyhow!("not a TTY"))?.0 .0 as u64,
-            base_digits,
-            group_bytes.into(),
-        )
+        max_panels_fn(terminal_width, base_digits, group_bytes.into())
     } else if let Some(panels) = matches
         .get_one::<String>("panels")
         .map(|s| {