fix bmp checking

Author: cometkim

README.md

@@ -220,7 +220,7 @@ Since [Hermes doesn't support the `Intl.Segmenter` API](https://github.com/faceb
 
 | Name                         | Unicode® | ESM? |   Size    | Size (min) | Size (min+gzip) | Size (min+br) | Size (min+zstd) |
 |------------------------------|----------|------|----------:|-----------:|----------------:|--------------:|----------------:|
-| `unicode-segmenter/grapheme` |   16.0.0 |   ✔️ |    15,586 |     12,166 |           5,037 |         3,717 |           4,726 |
+| `unicode-segmenter/grapheme` |   16.0.0 |   ✔️ |    15,588 |     12,168 |           5,038 |         3,715 |           4,727 |
 | `graphemer`                  |   15.0.0 |   ✖️ ️|   410,435 |     95,104 |          15,752 |        10,660 |          15,911 |
 | `grapheme-splitter`          |   10.0.0 |   ✖️ |   122,252 |     23,680 |           7,852 |         4,841 |           6,750 |
 | `@formatjs/intl-segmenter`*  |   15.0.0 |   ✖️ |   603,285 |    369,560 |          72,218 |        49,416 |          67,975 |
@@ -236,7 +236,7 @@ Since [Hermes doesn't support the `Intl.Segmenter` API](https://github.com/faceb
 
 | Name                         | Bytecode size | Bytecode size (gzip)* |
 |------------------------------|--------------:|----------------------:|
-| `unicode-segmenter/grapheme` |        21,001 |                11,063 |
+| `unicode-segmenter/grapheme` |        21,001 |                11,065 |
 | `graphemer`                  |       133,978 |                31,713 |
 | `grapheme-splitter`          |        63,835 |                19,137 |
 

src/grapheme.js

@@ -49,7 +49,7 @@ export function* graphemeSegments(input) {
   if (cp == null) return;
 
   /** Current cursor position. */
-  let cursor = cp < 0xFFFF ? 1 : 2;
+  let cursor = cp <= 0xFFFF ? 1 : 2;
 
   /** Total length of the input string. */
   let len = input.length;
@@ -137,7 +137,7 @@ export function* graphemeSegments(input) {
       _hd = cp;
     }
 
-    cursor += cp < 0xFFFF ? 1 : 2;
+    cursor += cp <= 0xFFFF ? 1 : 2;
     catBefore = catAfter;
   }