Make escapeHtml faster

Author: zaaack

docs/server-side-rendering.md

@@ -274,45 +274,45 @@ Here is the benchmark result on a linux laptop (Intel Core i7-3630QM, 8 core), r
 
 dotnet ./bin/Release/netcoreapp2.0/dotnet.dll
 Thread 1 started
-Thread 1 render 160000 times used 25146ms
-[Single thread] 25146ms    6362.841req/s
+Thread 1 render 160000 times used 23062ms
+[Single thread] 23062ms    6937.820req/s
 Thread 1 started
 Thread 3 started
 Thread 4 started
+Thread 6 started
 Thread 5 started
 Thread 7 started
-Thread 8 started
+Thread 10 started
 Thread 9 started
-Thread 6 started
-Thread 3 render 20000 times used 10370ms
-Thread 9 render 20000 times used 10409ms
-Thread 6 render 20000 times used 10421ms
-Thread 4 render 20000 times used 10434ms
-Thread 7 render 20000 times used 10445ms
-Thread 1 render 20000 times used 10458ms
-Thread 5 render 20000 times used 10483ms
-Thread 8 render 20000 times used 10497ms
-[8 tasks] Total: 10439ms    Memory footprint: 43.266MB   Requests/sec: 15327.139
+Thread 3 render 20000 times used 9593ms
+Thread 5 render 20000 times used 9689ms
+Thread 10 render 20000 times used 9693ms
+Thread 9 render 20000 times used 9705ms
+Thread 4 render 20000 times used 9720ms
+Thread 1 render 20000 times used 9753ms
+Thread 7 render 20000 times used 9757ms
+Thread 6 render 20000 times used 9795ms
+[8 tasks] Total: 9713ms    Memory footprint: 44.063MB   Requests/sec: 16472.768
 
 /usr/local/bin/node ./node.js
-Master 3266 is running
-[Single process] 33702ms    4747.493req/s
-Worker 3275: started
-Worker 3281: started
-Worker 3303: started
-Worker 3289: started
-Worker 3304: started
-Worker 3296: started
-Worker 3320: started
-Worker 3317: started
-Worker 3281: render 20000 times used 10247ms
-Worker 3289: render 20000 times used 10709ms
-Worker 3275: render 20000 times used 11048ms
-Worker 3303: render 20000 times used 11119ms
-Worker 3296: render 20000 times used 11188ms
-Worker 3320: render 20000 times used 11359ms
-Worker 3304: render 20000 times used 11370ms
-Worker 3317: render 20000 times used 11574ms
-[8 workers] Total: 11076.75ms    Memory footprint: 200.066MB    Requests/sec: 14444.670
+Master 10891 is running
+[Single process] 34322ms    4661.733req/s
+Worker 10911: started
+Worker 10916: started
+Worker 10928: started
+Worker 10942: started
+Worker 10930: started
+Worker 10935: started
+Worker 10922: started
+Worker 10951: started
+Worker 10911: render 20000 times used 11394ms
+Worker 10935: render 20000 times used 11353ms
+Worker 10928: render 20000 times used 11522ms
+Worker 10922: render 20000 times used 11492ms
+Worker 10916: render 20000 times used 11812ms
+Worker 10930: render 20000 times used 11913ms
+Worker 10951: render 20000 times used 11781ms
+Worker 10942: render 20000 times used 12236ms
+[8 workers] Total: 11687.875ms    Memory footprint: 200.066MB    Requests/sec: 13689.400
 
 ```

src/Fable.React/Fable.Helpers.ReactServer.fs

@@ -15,22 +15,15 @@ let private voidTags = System.Collections.Generic.HashSet<_>(["area"; "base"; "b
 
 // Adapted from https://github.com/facebook/react/blob/37e4329bc81def4695211d6e3795a654ef4d84f5/packages/react-dom/src/server/escapeTextForBrowser.js#L49
 let escapeHtml (sb:StringBuilder) (str: string) =
-  let splits = str.Split('"', '\'', '&', '<', '>')
-  let mutable charIndex = -1
-  for i = 0 to splits.Length - 2 do
-    let part = splits.[i]
-    sb.Append part |> ignore
-    charIndex <- charIndex + part.Length + 1
-    let char = str.[charIndex]
-    match char with
+  for c in str.ToCharArray() do
+    match c with
     | '"' -> sb.Append("&quot")
     | '&' -> sb.Append("&amp;")
     | ''' -> sb.Append("&#x27;") // modified from escape-html; used to be '&#39'
     | '<' -> sb.Append("&lt;")
     | '>' -> sb.Append("&gt;")
     | c   -> sb.Append(c)
     |> ignore
-  sb.Append(Array.last splits) |> ignore
 
 let inline private addUnit (html:StringBuilder) (key: string) (value: string) =
   html.Append value |> ignore
@@ -40,7 +33,7 @@ let inline private addUnit (html:StringBuilder) (key: string) (value: string) =
 let private cssProp (html:StringBuilder) (key: string) (value: obj) =
   html.Append key |> ignore
   html.Append ':' |> ignore
-  
+
   match value with
   | :? int as v -> addUnit html key (string v)
   | :? float as v -> addUnit html key (string v)
@@ -622,7 +615,7 @@ let private renderHtmlAttr (html:StringBuilder) (attr: HTMLAttr) =
 
     for cssProp in cssList do
       renderCssProp html cssProp
-    
+
     html.Append '"' |> ignore
 
   | HTMLAttr.Custom (key, value) -> strAttr html (key.ToLower()) (string value)
@@ -723,9 +716,9 @@ let rec private addReactMark htmlNode =
   | h -> h
 
 let inline private castHTMLNode (htmlNode: ReactElement): HTMLNode =
-  if isNull htmlNode then 
+  if isNull htmlNode then
     HTMLNode.Empty
-  else 
+  else
     htmlNode :?> HTMLNode
 
 let renderToString (htmlNode: ReactElement): string =
@@ -742,11 +735,11 @@ let renderToString (htmlNode: ReactElement): string =
 
       let child = renderAttrs html attrs tag
 
-      if voidTags.Contains tag then 
+      if voidTags.Contains tag then
         html.Append "/>" |> ignore
-      else 
+      else
         html.Append '>' |> ignore
-        
+
         match child with
         | Some c -> html.Append c |> ignore
         | None ->