From 7df64a0a23d4ce6f7f3f5f77abd154711dab6e92 Mon Sep 17 00:00:00 2001
From: Alfonso Garcia-Caro <alfonso.garcia-caro@hotmail.com>
Date: Tue, 28 Aug 2018 22:56:38 +0200
Subject: [PATCH] Use getUnicodeCategory for Char/isWhitespace

---
 src/js/fable-core/Char.ts | 11 ++++++++++-
 tests/Main/CharTests.fs   |  7 ++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/js/fable-core/Char.ts b/src/js/fable-core/Char.ts
index 3d78a7aaaf..9933effd40 100644
--- a/src/js/fable-core/Char.ts
+++ b/src/js/fable-core/Char.ts
@@ -117,6 +117,10 @@ const isSymbolMask = 0
   | 1 << UnicodeCategory.CurrencySymbol
   | 1 << UnicodeCategory.ModifierSymbol
   | 1 << UnicodeCategory.OtherSymbol;
+const isWhiteSpaceMask = 0
+  | 1 << UnicodeCategory.SpaceSeparator
+  | 1 << UnicodeCategory.LineSeparator
+  | 1 << UnicodeCategory.ParagraphSeparator;
 
 export const getUnicodeCategory = getCategory();
 
@@ -171,7 +175,12 @@ export function isSymbol(s: string, index?: number) {
 }
 
 export function isWhiteSpace(s: string, index?: number) {
-  return /[\s\x09-\x0D\x85\xA0]/.test(s.charAt(index || 0));
+  const test = 1 << getUnicodeCategory(s, index);
+  if ((test & isWhiteSpaceMask) !== 0) {
+    return true;
+  }
+  const cp = s.charCodeAt(index || 0);
+  return (0x09 <= cp && cp <= 0x0D) || cp === 0x85 || cp === 0xA0;
 }
 
 export function isHighSurrogate(s: string, index?: number) {
diff --git a/tests/Main/CharTests.fs b/tests/Main/CharTests.fs
index 7019d50a0e..aa98c16d38 100644
--- a/tests/Main/CharTests.fs
+++ b/tests/Main/CharTests.fs
@@ -37,7 +37,7 @@ let tests =
             Char.GetUnicodeCategory(str,2) |> int |> equal 8 //UnicodeCategory.DecimalDigitNumber
 
         testCase "Char.IsControl works" <| fun () ->
-            Char.IsControl('a') |> equal false 
+            Char.IsControl('a') |> equal false
             Char.IsControl('\u0000') |> equal true
             Char.IsControl('\u001F') |> equal true
             Char.IsControl('\u007F') |> equal true
@@ -142,6 +142,11 @@ let tests =
             Char.IsWhiteSpace(' ') |> equal true
             Char.IsWhiteSpace('\n') |> equal true
             Char.IsWhiteSpace('\t') |> equal true
+            Char.IsWhiteSpace('\009') |> equal true
+            Char.IsWhiteSpace('\013') |> equal true
+            Char.IsWhiteSpace('\133') |> equal true
+            Char.IsWhiteSpace('\160') |> equal true
+            Char.IsWhiteSpace('-') |> equal false
 
         testCase "Char.IsWhitespace works with two args" <| fun () ->
             let input = " \r"