From 8a03ac6caa4095a14ef1f3d84db67e9dd4bf8b6e Mon Sep 17 00:00:00 2001
From: Jeong YunWon <jeong@youknowone.org>
Date: Thu, 10 Jun 2021 12:03:25 +0900
Subject: [PATCH 1/2] Prevent double scanning from dircolors

---
 src/uu/dircolors/src/dircolors.rs | 35 +++++++++++++++++--------------
 1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/src/uu/dircolors/src/dircolors.rs b/src/uu/dircolors/src/dircolors.rs
index 2fa2e8b91..80c94c047 100644
--- a/src/uu/dircolors/src/dircolors.rs
+++ b/src/uu/dircolors/src/dircolors.rs
@@ -191,24 +191,27 @@ pub trait StrUtils {
 
 impl StrUtils for str {
     fn purify(&self) -> &Self {
-        let mut line = self;
-        for (n, c) in self.chars().enumerate() {
-            if c != '#' {
-                continue;
-            }
-
+        let line = if self.as_bytes().first() == Some(&b'#') {
             // Ignore if '#' is at the beginning of line
-            if n == 0 {
-                line = &self[..0];
-                break;
+            &self[..0]
+        } else {
+            let mut line = self;
+            for (n, _) in self
+                .as_bytes()
+                .iter()
+                .enumerate()
+                .rev()
+                .filter(|(_, c)| **c == b'#')
+            {
+                // Ignore the content after '#'
+                // only if it is preceded by at least one whitespace
+                if self[..n].chars().last().unwrap().is_whitespace() {
+                    line = &self[..n];
+                    break;
+                }
             }
-
-            // Ignore the content after '#'
-            // only if it is preceded by at least one whitespace
-            if self.chars().nth(n - 1).unwrap().is_whitespace() {
-                line = &self[..n];
-            }
-        }
+            line
+        };
         line.trim()
     }
 

From e3197bea39ca6093126dbdf1d24d834f03e09837 Mon Sep 17 00:00:00 2001
From: Jeong YunWon <jeong@youknowone.org>
Date: Thu, 10 Jun 2021 18:14:23 +0900
Subject: [PATCH 2/2] dircolor purify forward match '#'

---
 src/uu/dircolors/src/dircolors.rs | 37 ++++++++++++++++---------------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/src/uu/dircolors/src/dircolors.rs b/src/uu/dircolors/src/dircolors.rs
index 80c94c047..530f051b3 100644
--- a/src/uu/dircolors/src/dircolors.rs
+++ b/src/uu/dircolors/src/dircolors.rs
@@ -191,27 +191,28 @@ pub trait StrUtils {
 
 impl StrUtils for str {
     fn purify(&self) -> &Self {
-        let line = if self.as_bytes().first() == Some(&b'#') {
-            // Ignore if '#' is at the beginning of line
-            &self[..0]
-        } else {
-            let mut line = self;
-            for (n, _) in self
-                .as_bytes()
-                .iter()
-                .enumerate()
-                .rev()
-                .filter(|(_, c)| **c == b'#')
-            {
-                // Ignore the content after '#'
-                // only if it is preceded by at least one whitespace
-                if self[..n].chars().last().unwrap().is_whitespace() {
-                    line = &self[..n];
+        let mut line = self;
+        for (n, _) in self
+            .as_bytes()
+            .iter()
+            .enumerate()
+            .filter(|(_, c)| **c == b'#')
+        {
+            // Ignore the content after '#'
+            // only if it is preceded by at least one whitespace
+            match self[..n].chars().last() {
+                Some(c) if c.is_whitespace() => {
+                    line = &self[..n - c.len_utf8()];
                     break;
                 }
+                None => {
+                    // n == 0
+                    line = &self[..0];
+                    break;
+                }
+                _ => (),
             }
-            line
-        };
+        }
         line.trim()
     }