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authorDarius Jahandarie <djahandarie@gmail.com>2023-11-03 23:32:33 +0900
committerDarius Jahandarie <djahandarie@gmail.com>2023-11-03 23:52:30 +0900
commit376151096431d4362e4baaacf0cef4a534e169f7 (patch)
tree18536a224fd4d833aaf691d0363a3a4b59175dd7 /ext/lib/ucs2length.js
parentb64f51c3b13a46af4dd7f1e43048ac19c781ca7b (diff)
Replace JsonSchema with ajv for dictionary validation
Diffstat (limited to 'ext/lib/ucs2length.js')
-rw-r--r--ext/lib/ucs2length.js16
1 files changed, 16 insertions, 0 deletions
diff --git a/ext/lib/ucs2length.js b/ext/lib/ucs2length.js
new file mode 100644
index 00000000..120a64d4
--- /dev/null
+++ b/ext/lib/ucs2length.js
@@ -0,0 +1,16 @@
+export default function ucs2length(str) {
+ const len = str.length;
+ let length = 0;
+ let pos = 0;
+ let value;
+ while (pos < len) {
+ length++;
+ value = str.charCodeAt(pos++);
+ if (value >= 0xd800 && value <= 0xdbff && pos < len) {
+ // high surrogate, and there is a next character
+ value = str.charCodeAt(pos);
+ if ((value & 0xfc00) === 0xdc00) pos++; // low surrogate
+ }
+ }
+ return length;
+}