fix(napi): JsString should respect \0 character to align with String (#2138)

* fix(napi): JsString should respect \0 character to align with String

* chore(test): update snapshot

crates/napi/src/js_values/string/mod.rs

@@ -69,9 +69,13 @@ impl JsString {
       )
     })?;
 
+    // respect '\0' with js string, for example: `let hello = [a,'\0',b,'\0',c].join('')`
+    let mut result = mem::ManuallyDrop::new(result);
+    let buf_ptr = result.as_mut_ptr();
+    let bytes = unsafe { Vec::from_raw_parts(buf_ptr as *mut u8, written_char_count, len) };
     Ok(JsStringUtf8 {
       inner: self,
-      buf: result,
+      buf: bytes,
     })
   }
 

crates/napi/src/js_values/string/utf8.rs

@@ -1,24 +1,26 @@
 use std::convert::TryFrom;
-use std::ffi::CStr;
-use std::os::raw::c_char;
 use std::str;
 
 use crate::{Error, JsString, Result, Status};
 
 pub struct JsStringUtf8 {
   pub(crate) inner: JsString,
-  pub(crate) buf: Vec<c_char>,
+  pub(crate) buf: Vec<u8>,
 }
 
 impl JsStringUtf8 {
   pub fn as_str(&self) -> Result<&str> {
-    unsafe { CStr::from_ptr(self.buf.as_ptr()) }
-      .to_str()
-      .map_err(|e| Error::new(Status::InvalidArg, format!("{}", e)))
+    match str::from_utf8(&self.buf) {
+      Err(e) => Err(Error::new(
+        Status::InvalidArg,
+        format!("Failed to read utf8 string, {}", e),
+      )),
+      Ok(s) => Ok(s),
+    }
   }
 
   pub fn as_slice(&self) -> &[u8] {
-    unsafe { CStr::from_ptr(self.buf.as_ptr()) }.to_bytes()
+    self.buf.as_slice()
   }
 
   pub fn len(&self) -> usize {

examples/napi-compat-mode/__tests__/string.spec.ts

@@ -7,6 +7,12 @@ test('should be able to concat string', (t) => {
   t.snapshot(bindings.concatString(fixture))
 })
 
+test('should be able to concat string with char \0', (t) => {
+  const fixture = 'JavaScript \0 🌳 你好 \0 napi'
+  t.snapshot(fixture)
+  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))