From bcb69c61dfdba00e4fbd2ad0f983e8162507383a Mon Sep 17 00:00:00 2001
From: Shotaro Yamada <sinkuu@sinkuu.xyz>
Date: Fri, 10 Jan 2020 00:49:00 +0900
Subject: [PATCH 1/2] Do not count spaces

---
 lib/smol_str/src/lib.rs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/smol_str/src/lib.rs b/lib/smol_str/src/lib.rs
index 9e35158177..c0c61c80d7 100644
--- a/lib/smol_str/src/lib.rs
+++ b/lib/smol_str/src/lib.rs
@@ -359,9 +359,11 @@ impl Repr {
             }
 
             let newlines = text.bytes().take_while(|&b| b == b'\n').count();
-            let spaces = text[newlines..].bytes().take_while(|&b| b == b' ').count();
-            if newlines + spaces == len && newlines <= N_NEWLINES && spaces <= N_SPACES {
-                return Repr::Substring { newlines, spaces };
+            if text[newlines..].bytes().all(|b| b == b' ') {
+                let spaces = len - newlines;
+                if newlines <= N_NEWLINES && spaces <= N_SPACES {
+                    return Repr::Substring { newlines, spaces };
+                }
             }
         }
 

From f7821f55c85cdbfdcd042f393075387bcb8960e5 Mon Sep 17 00:00:00 2001
From: Shotaro Yamada <sinkuu@sinkuu.xyz>
Date: Fri, 10 Jan 2020 00:50:08 +0900
Subject: [PATCH 2/2] Improve `Arc<str>` creation

While using `Into` could avoid an allocation in `String` -> `Box<str>`,
converting `Box<str>` into `Arc<str>` deallocates and re-allocates anyway.
---
 lib/smol_str/src/lib.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/smol_str/src/lib.rs b/lib/smol_str/src/lib.rs
index c0c61c80d7..e4cca47176 100644
--- a/lib/smol_str/src/lib.rs
+++ b/lib/smol_str/src/lib.rs
@@ -104,7 +104,7 @@ impl SmolStr {
 
     pub fn new<T>(text: T) -> SmolStr
     where
-        T: Into<String> + AsRef<str>,
+        T: AsRef<str>,
     {
         SmolStr(Repr::new(text))
     }
@@ -343,7 +343,7 @@ enum Repr {
 impl Repr {
     fn new<T>(text: T) -> Self
     where
-        T: Into<String> + AsRef<str>,
+        T: AsRef<str>,
     {
         {
             let text = text.as_ref();
@@ -367,7 +367,7 @@ impl Repr {
             }
         }
 
-        Repr::Heap(text.into().into_boxed_str().into())
+        Repr::Heap(text.as_ref().into())
     }
 
     #[inline(always)]