cleanup the escape condition (#96)

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 |   ✔️ |    15,607 |     12,166 |           5,042 |         3,747 |           4,725 |
+| `unicode-segmenter/grapheme` |   16.0.0 |   ✔️ |    15,586 |     12,166 |           5,037 |         3,717 |           4,726 |
 | `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` |        20,932 |                10,991 |
+| `unicode-segmenter/grapheme` |        21,001 |                11,063 |
 | `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 = 0;
+  let cursor = cp < 0xFFFF ? 1 : 2;
 
   /** Total length of the input string. */
   let len = input.length;
@@ -86,21 +86,7 @@ export function* graphemeSegments(input) {
   /** Memoize the beginnig code point a the segment. */
   let _hd = cp;
 
-  while (true) {
-    cursor += cp < 0xFFFF ? 1 : 2;
-
-    if (cursor >= len) {
-      yield {
-        segment: input.slice(index, cursor),
-        index,
-        input,
-        _hd,
-        _catBegin,
-        _catEnd: catBefore,
-      };
-      return;
-    }
-
+  while (cursor < len) {
     // Note: Lazily update `consonant` and `linker` state
     // which is a extra overhead only for Hindi text.
     if (cp >= 2325) {
@@ -151,8 +137,20 @@ export function* graphemeSegments(input) {
       _hd = cp;
     }
 
+    cursor += cp < 0xFFFF ? 1 : 2;
     catBefore = catAfter;
   }
+
+  if (index < len) {
+    yield {
+      segment: input.slice(index),
+      index,
+      input,
+      _hd,
+      _catBegin,
+      _catEnd: catBefore,
+    };
+  }
 }
 
 /**