From 43bbf004781f06d62acf3952a4c5dd343ce1079a Mon Sep 17 00:00:00 2001
From: Benjamin Sago <ogham@bsago.me>
Date: Wed, 13 Sep 2017 23:47:19 +0100
Subject: [PATCH] =?UTF-8?q?Show=20a=20warning=20when=20running=20=E2=80=98?=
 =?UTF-8?q?exa=20-ltr=E2=80=99?=
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Raised in #243 and #284. exa isn’t able to override the -t option like this, so the least it can do is detect that case (which is going to be an error case anyway) and show a suggestion.
---
 src/bin/main.rs        |  8 +++++++-
 src/options/misfire.rs | 14 +++++++++++++-
 xtests/error_ltr       |  2 ++
 xtests/run.sh          |  3 +++
 4 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 xtests/error_ltr

diff --git a/src/bin/main.rs b/src/bin/main.rs
index 0119ee5..7e4a082 100644
--- a/src/bin/main.rs
+++ b/src/bin/main.rs
@@ -28,7 +28,13 @@ fn main() {
         },
 
         Err(ref e) if e.is_error() => {
-            writeln!(stderr(), "{}", e).unwrap();
+            let mut stderr = stderr();
+            writeln!(stderr, "{}", e).unwrap();
+
+            if let Some(s) = e.suggestion() {
+                let _ = writeln!(stderr, "{}", s);
+            }
+
             exit(exits::OPTIONS_ERROR);
         },
 
diff --git a/src/options/misfire.rs b/src/options/misfire.rs
index 1b28179..42e4bc2 100644
--- a/src/options/misfire.rs
+++ b/src/options/misfire.rs
@@ -4,7 +4,7 @@ use std::num::ParseIntError;
 
 use glob;
 
-use options::{HelpString, VersionString};
+use options::{flags, HelpString, VersionString};
 use options::parser::{Arg, Flag, ParseError};
 
 
@@ -120,3 +120,15 @@ impl fmt::Display for ParseError {
         }
     }
 }
+
+impl Misfire {
+    pub fn suggestion(&self) -> Option<&'static str> {
+        if let Misfire::BadArgument(ref time, ref r, ref _choices) = *self {
+            if *time == &flags::TIME && r == "r" {
+                return Some("To sort newest files first, try \"--sort modified\", or just \"-stime\"");
+            }
+        }
+
+        None
+    }
+}
diff --git a/xtests/error_ltr b/xtests/error_ltr
new file mode 100644
index 0000000..84bbe47
--- /dev/null
+++ b/xtests/error_ltr
@@ -0,0 +1,2 @@
+Option --time (-t) has no "r" setting (choices: modified, accessed, created)
+To sort newest files first, try "--sort modified", or just "-stime"
diff --git a/xtests/run.sh b/xtests/run.sh
index 572c3b7..e2164ed 100755
--- a/xtests/run.sh
+++ b/xtests/run.sh
@@ -263,6 +263,9 @@ $exa -l --long          2>&1 | diff -q - $results/error_duplicate   || exit 1
 $exa -ll                2>&1 | diff -q - $results/error_twice       || exit 1
 $exa -l --time-style=24 2>&1 | diff -q - $results/error_setting     || exit 1
 
+# Error suggestions
+$exa -ltr 2>&1 | diff -q - $results/error_ltr  || exit 1
+
 
 # Debug mode
 # (uses an empty directory so it prints nothing to stdout)