fix(napi): utf16 value should not contains 0 terminate

napi/src/js_values/string/mod.rs

@@ -68,7 +68,7 @@ impl JsString {
   pub fn into_utf16(self) -> Result<JsStringUtf16> {
     let mut written_char_count = 0usize;
     let len = self.utf16_len()? + 1;
-    let mut result = Vec::with_capacity(len);
+    let mut result = vec![0; len];
     let buf_ptr = result.as_mut_ptr();
     check_status!(unsafe {
       sys::napi_get_value_string_utf16(

napi/src/js_values/string/utf16.rs

@@ -11,8 +11,11 @@ pub struct JsStringUtf16 {
 impl JsStringUtf16 {
   #[inline]
   pub fn as_str(&self) -> Result<String> {
-    String::from_utf16(self.as_slice())
-      .map_err(|e| Error::new(Status::InvalidArg, format!("{}", e)))
+    if let Some((_, prefix)) = self.as_slice().split_last() {
+      String::from_utf16(prefix).map_err(|e| Error::new(Status::InvalidArg, format!("{}", e)))
+    } else {
+      Ok(String::new())
+    }
   }
 
   #[inline]

test_module/__test__/object.spec.ts.md

@@ -4,28 +4,17 @@ The actual snapshot is saved in `object.spec.ts.snap`.
 
 Generated by [AVA](https://avajs.dev).
 
-## setNamedProperty
-
-> Snapshot 1
-
-    'RustPropertyKey'
-
 ## setProperty
 
 > Snapshot 1
 
     'Rust object property'
 
-## testDeleteElement
+## setNamedProperty
 
 > Snapshot 1
 
-    [
-      0,
-      undefined,
-      undefined,
-      3,
-    ]
+    'RustPropertyKey'
 
 ## testGetPropertyNames
 
@@ -48,3 +37,14 @@ Generated by [AVA](https://avajs.dev).
       undefined,
       'foo',
     ]
+
+## testDeleteElement
+
+> Snapshot 1
+
+    [
+      0,
+      undefined,
+      undefined,
+      3,
+    ]

test_module/__test__/string.spec.ts

@@ -7,6 +7,11 @@ test('should be able to concat string', (t) => {
   t.snapshot(bindings.concatString(fixture))
 })
 
+test('should be able to concat utf16 string', (t) => {
+  const fixture = 'JavaScript 🌳 你好 napi'
+  t.snapshot(bindings.concatUTF16String(fixture))
+})
+
 test('should be able to concat latin1 string', (t) => {
   const fixture = '涽¾DEL'
   t.snapshot(bindings.concatLatin1String(fixture))

test_module/src/string.rs

@@ -7,6 +7,13 @@ fn concat_string(ctx: CallContext) -> Result<JsString> {
   ctx.env.create_string_from_std(out_string)
 }
 
+#[js_function(1)]
+fn concat_utf16_string(ctx: CallContext) -> Result<JsString> {
+  let in_string = ctx.get::<JsString>(0)?;
+  let out_string = format!("{} + Rust 🦀 string!", in_string.into_utf16()?.as_str()?);
+  ctx.env.create_string_from_std(out_string)
+}
+
 #[js_function(1)]
 fn concat_latin1_string(ctx: CallContext) -> Result<JsString> {
   let in_string = ctx.get::<JsString>(0)?;
@@ -25,6 +32,7 @@ fn create_latin1(ctx: CallContext) -> Result<JsString> {
 
 pub fn register_js(exports: &mut JsObject) -> Result<()> {
   exports.create_named_method("concatString", concat_string)?;
+  exports.create_named_method("concatUTF16String", concat_utf16_string)?;
   exports.create_named_method("concatLatin1String", concat_latin1_string)?;
   exports.create_named_method("createLatin1", create_latin1)?;
   Ok(())