feat(napi): BigInt codegen support

README.md

@@ -241,9 +241,9 @@ yarn test
 | Result<()>              | Error                  | 1                                                                               | v8.0.0               |
 | T: Fn(...) -> Result<T> | Function               | 1                                                                               | v8.0.0               |
 | Async/Future            | Promise<T>             | 4                                                                               | v10.6.0              | async                    |
-| Task                    | Promise<T>             | 1                                                                               | v8.5.0               |
+| AsyncTask               | Promise<T>             | 1                                                                               | v8.5.0               |
 | (NOT YET)               | global                 | 1                                                                               | v8.0.0               |
-| (NOT YET)               | Symbol                 | 1                                                                               | v8.0.0               |
+| JsSymbol                | Symbol                 | 1                                                                               | v8.0.0               |
 | (NOT YET)               | ArrayBuffer/TypedArray | 1                                                                               | v8.0.0               |
 | (NOT YET)               | threadsafe function    | 4                                                                               | v10.6.0              | napi4                    |
-| (NOT YET)               | BigInt                 | 6                                                                               | v10.7.0              | napi6                    |
+| BigInt                  | BigInt                 | 6                                                                               | v10.7.0              | napi6                    |

crates/backend/src/typegen.rs

@@ -40,10 +40,12 @@ static KNOWN_TYPES: Lazy<HashMap<&'static str, &'static str>> = Lazy::new(|| {
     ("u16", "number"),
     ("u32", "number"),
     ("u64", "BigInt"),
+    ("i64n", "BigInt"),
     ("u128", "BigInt"),
     ("i128", "BigInt"),
     ("usize", "BigInt"),
     ("isize", "BigInt"),
+    ("JsBigInt", "BigInt"),
     ("BigInt", "BigInt"),
     ("bool", "boolean"),
     ("String", "string"),

crates/napi/src/bindgen_runtime/js_values.rs

@@ -1,7 +1,10 @@
-use crate::{check_status, sys, Error, JsUnknown, NapiRaw, NapiValue, Result, Status, ValueType};
 use std::ptr;
 
+use crate::{check_status, sys, Error, JsUnknown, NapiRaw, NapiValue, Result, Status, ValueType};
+
 mod array;
+#[cfg(feature = "napi6")]
+mod bigint;
 mod boolean;
 mod buffer;
 mod either;
@@ -15,6 +18,8 @@ mod string;
 mod task;
 
 pub use array::*;
+#[cfg(feature = "napi6")]
+pub use bigint::*;
 pub use buffer::*;
 pub use either::*;
 pub use nil::*;

crates/napi/src/bindgen_runtime/js_values/bigint.rs

@@ -0,0 +1,211 @@
+/// We don't implement `FromNapiValue` for `i64` `u64` `i128` `u128` `isize` `usize` here
+/// Because converting directly from `JsBigInt` to these values may result in a loss of precision and thus unintended behavior
+/// ```rust
+/// use napi::{bindgen_prelude::*, JsBigint};
+///
+/// #[napi]
+/// fn bigint_add(mut a: Bigint, mut b: Bigint) -> u128 {
+///     a.get_u128().1 + b.get_u128().1 // We have opportunity to check if the `u128` has lost precision
+/// }
+/// ```
+use std::ptr;
+
+use crate::{check_status, sys};
+
+use super::{FromNapiValue, ToNapiValue, TypeName};
+
+/// i64 is converted to `Number`
+#[repr(transparent)]
+#[allow(non_camel_case_types)]
+pub struct i64n(pub i64);
+
+/// https://nodejs.org/api/n-api.html#napi_create_bigint_words
+/// The resulting BigInt is calculated as: (–1)^sign_bit (words[0] × (2^64)^0 + words[1] × (2^64)^1 + …)
+pub struct BigInt {
+  /// true for negative numbers
+  pub sign_bit: bool,
+  pub words: Vec<u64>,
+}
+
+impl TypeName for BigInt {
+  fn type_name() -> &'static str {
+    "BigInt"
+  }
+
+  fn value_type() -> crate::ValueType {
+    crate::ValueType::BigInt
+  }
+}
+
+impl FromNapiValue for BigInt {
+  unsafe fn from_napi_value(env: sys::napi_env, napi_val: sys::napi_value) -> crate::Result<Self> {
+    let mut word_count = 0usize;
+    check_status!(sys::napi_get_value_bigint_words(
+      env,
+      napi_val,
+      ptr::null_mut(),
+      &mut word_count,
+      ptr::null_mut(),
+    ))?;
+    let mut words: Vec<u64> = Vec::with_capacity(word_count as usize);
+    let mut sign_bit = 0;
+    check_status!(sys::napi_get_value_bigint_words(
+      env,
+      napi_val,
+      &mut sign_bit,
+      &mut word_count,
+      words.as_mut_ptr(),
+    ))?;
+
+    words.set_len(word_count as usize);
+    Ok(BigInt {
+      sign_bit: sign_bit == 1,
+      words,
+    })
+  }
+}
+
+impl BigInt {
+  /// (signed, value, lossless)
+  /// get the first word of the BigInt as `u64`
+  /// return true in the last element of tuple if the value is lossless
+  /// or the value is truncated
+  pub fn get_u64(&self) -> (bool, u64, bool) {
+    (
+      self.sign_bit,
+      self.words[0],
+      self.sign_bit && self.words.len() == 1,
+    )
+  }
+
+  /// (value, lossless)
+  /// get the first word of the BigInt as `i64`
+  /// return true if the value is lossless
+  /// or the value is truncated
+  pub fn get_i64(&self) -> (i64, bool) {
+    let val = self.words[0] as i64;
+    (val, val as u64 == self.words[0] && self.words.len() == 1)
+  }
+
+  /// (value, lossless)
+  /// get the first two words of the BigInt as `i128`
+  /// return true if the value is lossless
+  /// or the value is truncated
+  pub fn get_i128(&self) -> (i128, bool) {
+    let len = self.words.len();
+    if len == 1 {
+      (self.words[0] as i128, false)
+    } else {
+      let i128_words: [i64; 2] = [self.words[0] as _, self.words[1] as _];
+      let mut val = unsafe { ptr::read(i128_words.as_ptr() as *const i128) };
+      if self.sign_bit {
+        val = -val;
+      }
+      (val, len > 2)
+    }
+  }
+
+  /// (signed, value, lossless)
+  /// get the first two words of the BigInt as `u128`
+  /// return true if the value is lossless
+  /// or the value is truncated
+  pub fn get_u128(&self) -> (bool, u128, bool) {
+    let len = self.words.len();
+    if len == 1 {
+      (self.sign_bit, self.words[0] as u128, false)
+    } else {
+      let u128_words: [u64; 2] = [self.words[0], self.words[1]];
+      let val = unsafe { ptr::read(u128_words.as_ptr() as *const u128) };
+      (self.sign_bit, val, len > 2)
+    }
+  }
+}
+
+impl ToNapiValue for BigInt {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    let len = val.words.len();
+    check_status!(sys::napi_create_bigint_words(
+      env,
+      match val.sign_bit {
+        true => 1,
+        false => 0,
+      },
+      len,
+      val.words.as_ptr(),
+      &mut raw_value,
+    ))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for i128 {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    let sign_bit = if val > 0 { 0 } else { 1 };
+    let words = &val as *const i128 as *const u64;
+    check_status!(sys::napi_create_bigint_words(
+      env,
+      sign_bit,
+      2,
+      words,
+      &mut raw_value
+    ))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for u128 {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    let words = &val as *const u128 as *const u64;
+    check_status!(sys::napi_create_bigint_words(
+      env,
+      0,
+      2,
+      words,
+      &mut raw_value
+    ))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for i64n {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    check_status!(sys::napi_create_bigint_int64(env, val.0, &mut raw_value))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for u64 {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    check_status!(sys::napi_create_bigint_uint64(env, val, &mut raw_value))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for usize {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    check_status!(sys::napi_create_bigint_uint64(
+      env,
+      val as u64,
+      &mut raw_value
+    ))?;
+    Ok(raw_value)
+  }
+}
+
+impl ToNapiValue for isize {
+  unsafe fn to_napi_value(env: sys::napi_env, val: Self) -> crate::Result<sys::napi_value> {
+    let mut raw_value = ptr::null_mut();
+    check_status!(sys::napi_create_bigint_int64(
+      env,
+      val as i64,
+      &mut raw_value
+    ))?;
+    Ok(raw_value)
+  }
+}

crates/napi/src/bindgen_runtime/js_values/serde.rs

@@ -56,7 +56,7 @@ impl FromNapiValue for Value {
         }
       }
       #[cfg(feature = "napi6")]
-      ValueType::Bigint => todo!(),
+      ValueType::BigInt => todo!(),
       _ => Value::Null,
     };
 

crates/napi/src/env.rs

@@ -100,43 +100,43 @@ impl Env {
 
   /// [n_api_napi_create_bigint_int64](https://nodejs.org/api/n-api.html#n_api_napi_create_bigint_int64)
   #[cfg(feature = "napi6")]
-  pub fn create_bigint_from_i64(&self, value: i64) -> Result<JsBigint> {
+  pub fn create_bigint_from_i64(&self, value: i64) -> Result<JsBigInt> {
     let mut raw_value = ptr::null_mut();
     check_status!(unsafe { sys::napi_create_bigint_int64(self.0, value, &mut raw_value) })?;
-    Ok(JsBigint::from_raw_unchecked(self.0, raw_value, 1))
+    Ok(JsBigInt::from_raw_unchecked(self.0, raw_value, 1))
   }
 
   #[cfg(feature = "napi6")]
-  pub fn create_bigint_from_u64(&self, value: u64) -> Result<JsBigint> {
+  pub fn create_bigint_from_u64(&self, value: u64) -> Result<JsBigInt> {
     let mut raw_value = ptr::null_mut();
     check_status!(unsafe { sys::napi_create_bigint_uint64(self.0, value, &mut raw_value) })?;
-    Ok(JsBigint::from_raw_unchecked(self.0, raw_value, 1))
+    Ok(JsBigInt::from_raw_unchecked(self.0, raw_value, 1))
   }
 
   #[cfg(feature = "napi6")]
-  pub fn create_bigint_from_i128(&self, value: i128) -> Result<JsBigint> {
+  pub fn create_bigint_from_i128(&self, value: i128) -> Result<JsBigInt> {
     let mut raw_value = ptr::null_mut();
     let sign_bit = if value > 0 { 0 } else { 1 };
     let words = &value as *const i128 as *const u64;
     check_status!(unsafe {
       sys::napi_create_bigint_words(self.0, sign_bit, 2, words, &mut raw_value)
     })?;
-    Ok(JsBigint::from_raw_unchecked(self.0, raw_value, 1))
+    Ok(JsBigInt::from_raw_unchecked(self.0, raw_value, 1))
   }
 
   #[cfg(feature = "napi6")]
-  pub fn create_bigint_from_u128(&self, value: u128) -> Result<JsBigint> {
+  pub fn create_bigint_from_u128(&self, value: u128) -> Result<JsBigInt> {
     let mut raw_value = ptr::null_mut();
     let words = &value as *const u128 as *const u64;
     check_status!(unsafe { sys::napi_create_bigint_words(self.0, 0, 2, words, &mut raw_value) })?;
-    Ok(JsBigint::from_raw_unchecked(self.0, raw_value, 1))
+    Ok(JsBigInt::from_raw_unchecked(self.0, raw_value, 1))
   }
 
   /// [n_api_napi_create_bigint_words](https://nodejs.org/api/n-api.html#n_api_napi_create_bigint_words)
   ///
   /// The resulting BigInt will be negative when sign_bit is true.
   #[cfg(feature = "napi6")]
-  pub fn create_bigint_from_words(&self, sign_bit: bool, words: Vec<u64>) -> Result<JsBigint> {
+  pub fn create_bigint_from_words(&self, sign_bit: bool, words: Vec<u64>) -> Result<JsBigInt> {
     let mut raw_value = ptr::null_mut();
     let len = words.len();
     check_status!(unsafe {
@@ -151,7 +151,7 @@ impl Env {
         &mut raw_value,
       )
     })?;
-    Ok(JsBigint::from_raw_unchecked(self.0, raw_value, len))
+    Ok(JsBigInt::from_raw_unchecked(self.0, raw_value, len))
   }
 
   pub fn create_string(&self, s: &str) -> Result<JsString> {

crates/napi/src/js_values/bigint.rs

@@ -5,22 +5,22 @@ use super::*;
 use crate::{bindgen_runtime::TypeName, check_status, sys, Result};
 
 #[derive(Clone, Copy)]
-pub struct JsBigint {
+pub struct JsBigInt {
   pub(crate) raw: Value,
   pub word_count: usize,
 }
 
-impl TypeName for JsBigint {
+impl TypeName for JsBigInt {
   fn type_name() -> &'static str {
     "BigInt"
   }
 
   fn value_type() -> ValueType {
-    ValueType::Bigint
+    ValueType::BigInt
   }
 }
 
-impl JsBigint {
+impl JsBigInt {
   pub(crate) fn from_raw_unchecked(
     env: sys::napi_env,
     value: sys::napi_value,
@@ -76,7 +76,6 @@ impl JsBigint {
     }))
   }
 
-  #[cfg(feature = "napi5")]
   pub fn is_date(&self) -> Result<bool> {
     let mut is_date = true;
     check_status!(unsafe { sys::napi_is_date(self.raw.env, self.raw.value, &mut is_date) })?;
@@ -122,19 +121,19 @@ impl JsBigint {
   }
 }
 
-impl NapiRaw for JsBigint {
+impl NapiRaw for JsBigInt {
   unsafe fn raw(&self) -> sys::napi_value {
     self.raw.value
   }
 }
 
-impl<'env> NapiRaw for &'env JsBigint {
+impl<'env> NapiRaw for &'env JsBigInt {
   unsafe fn raw(&self) -> sys::napi_value {
     self.raw.value
   }
 }
 
-impl NapiValue for JsBigint {
+impl NapiValue for JsBigInt {
   unsafe fn from_raw(env: sys::napi_env, value: sys::napi_value) -> Result<Self> {
     let mut word_count = 0usize;
     check_status!(sys::napi_get_value_bigint_words(
@@ -144,11 +143,11 @@ impl NapiValue for JsBigint {
       &mut word_count,
       ptr::null_mut(),
     ))?;
-    Ok(JsBigint {
+    Ok(JsBigInt {
       raw: Value {
         env,
         value,
-        value_type: ValueType::Bigint,
+        value_type: ValueType::BigInt,
       },
       word_count,
     })
@@ -167,11 +166,11 @@ impl NapiValue for JsBigint {
       Status::from(status) == Status::Ok,
       "napi_get_value_bigint_words failed"
     );
-    JsBigint {
+    JsBigInt {
       raw: Value {
         env,
         value,
-        value_type: ValueType::Bigint,
+        value_type: ValueType::BigInt,
       },
       word_count,
     }
@@ -179,24 +178,24 @@ impl NapiValue for JsBigint {
 }
 
 /// The BigInt will be converted losslessly when the value is over what an int64 could hold.
-impl TryFrom<JsBigint> for i64 {
+impl TryFrom<JsBigInt> for i64 {
   type Error = Error;
 
-  fn try_from(value: JsBigint) -> Result<i64> {
+  fn try_from(value: JsBigInt) -> Result<i64> {
     value.get_i64().map(|(v, _)| v)
   }
 }
 
 /// The BigInt will be converted losslessly when the value is over what an uint64 could hold.
-impl TryFrom<JsBigint> for u64 {
+impl TryFrom<JsBigInt> for u64 {
   type Error = Error;
 
-  fn try_from(value: JsBigint) -> Result<u64> {
+  fn try_from(value: JsBigInt) -> Result<u64> {
     value.get_u64().map(|(v, _)| v)
   }
 }
 
-impl JsBigint {
+impl JsBigInt {
   /// https://nodejs.org/api/n-api.html#n_api_napi_get_value_bigint_words
   pub fn get_words(&mut self) -> Result<(bool, Vec<u64>)> {
     let mut words: Vec<u64> = Vec::with_capacity(self.word_count as usize);
@@ -221,21 +220,21 @@ impl JsBigint {
 
   pub fn get_u64(&self) -> Result<(u64, bool)> {
     let mut val: u64 = 0;
-    let mut loss = false;
+    let mut lossless = false;
     check_status!(unsafe {
-      sys::napi_get_value_bigint_uint64(self.raw.env, self.raw.value, &mut val, &mut loss)
+      sys::napi_get_value_bigint_uint64(self.raw.env, self.raw.value, &mut val, &mut lossless)
     })?;
 
-    Ok((val, loss))
+    Ok((val, lossless))
   }
 
   pub fn get_i64(&self) -> Result<(i64, bool)> {
     let mut val: i64 = 0;
-    let mut loss: bool = false;
+    let mut lossless: bool = false;
     check_status!(unsafe {
-      sys::napi_get_value_bigint_int64(self.raw.env, self.raw.value, &mut val, &mut loss)
+      sys::napi_get_value_bigint_int64(self.raw.env, self.raw.value, &mut val, &mut lossless)
     })?;
-    Ok((val, loss))
+    Ok((val, lossless))
   }
 
   pub fn get_i128(&mut self) -> Result<(i128, bool)> {

crates/napi/src/js_values/de.rs

@@ -4,7 +4,7 @@ use serde::de::Visitor;
 use serde::de::{DeserializeSeed, EnumAccess, MapAccess, SeqAccess, Unexpected, VariantAccess};
 
 #[cfg(feature = "napi6")]
-use crate::JsBigint;
+use crate::JsBigInt;
 use crate::{type_of, NapiValue, Value, ValueType};
 use crate::{
   Error, JsBoolean, JsBufferValue, JsNumber, JsObject, JsString, JsUnknown, Result, Status,
@@ -54,8 +54,8 @@ impl<'x, 'de, 'env> serde::de::Deserializer<'x> for &'de mut De<'env> {
         }
       }
       #[cfg(feature = "napi6")]
-      ValueType::Bigint => {
+      ValueType::BigInt => {
-        let mut js_bigint = unsafe { JsBigint::from_raw(self.0.env, self.0.value)? };
+        let mut js_bigint = unsafe { JsBigInt::from_raw(self.0.env, self.0.value)? };
         let (signed, v, _loss) = js_bigint.get_u128()?;
         if signed {
           visitor.visit_i128(-(v as i128))

crates/napi/src/js_values/mod.rs

@@ -33,7 +33,7 @@ mod value_ref;
 
 pub use arraybuffer::*;
 #[cfg(feature = "napi6")]
-pub use bigint::JsBigint;
+pub use bigint::JsBigInt;
 pub use boolean::JsBoolean;
 pub use buffer::*;
 #[cfg(feature = "napi5")]

crates/napi/src/value_type.rs

@@ -15,7 +15,7 @@ pub enum ValueType {
   Function = 7,
   External = 8,
   #[cfg(feature = "napi6")]
-  Bigint = 9,
+  BigInt = 9,
   Unknown = 1024,
 }
 
@@ -30,7 +30,7 @@ impl From<i32> for ValueType {
   fn from(value: i32) -> ValueType {
     match value {
       #[cfg(feature = "napi6")]
-      sys::ValueType::napi_bigint => ValueType::Bigint,
+      sys::ValueType::napi_bigint => ValueType::BigInt,
       sys::ValueType::napi_boolean => ValueType::Boolean,
       sys::ValueType::napi_external => ValueType::External,
       sys::ValueType::napi_function => ValueType::Function,

examples/napi-compat-mode/src/napi6/bigint.rs

@@ -1,28 +1,28 @@
-use napi::{CallContext, JsBigint, JsNumber, JsObject, Result};
+use napi::{CallContext, JsBigInt, JsNumber, JsObject, Result};
 use std::convert::TryFrom;
 
 #[js_function]
-pub fn test_create_bigint_from_i64(ctx: CallContext) -> Result<JsBigint> {
+pub fn test_create_bigint_from_i64(ctx: CallContext) -> Result<JsBigInt> {
   ctx.env.create_bigint_from_i64(i64::max_value())
 }
 
 #[js_function]
-pub fn test_create_bigint_from_u64(ctx: CallContext) -> Result<JsBigint> {
+pub fn test_create_bigint_from_u64(ctx: CallContext) -> Result<JsBigInt> {
   ctx.env.create_bigint_from_u64(u64::max_value())
 }
 
 #[js_function]
-pub fn test_create_bigint_from_i128(ctx: CallContext) -> Result<JsBigint> {
+pub fn test_create_bigint_from_i128(ctx: CallContext) -> Result<JsBigInt> {
   ctx.env.create_bigint_from_i128(i128::max_value())
 }
 
 #[js_function]
-pub fn test_create_bigint_from_u128(ctx: CallContext) -> Result<JsBigint> {
+pub fn test_create_bigint_from_u128(ctx: CallContext) -> Result<JsBigInt> {
   ctx.env.create_bigint_from_u128(u128::max_value())
 }
 
 #[js_function]
-pub fn test_create_bigint_from_words(ctx: CallContext) -> Result<JsBigint> {
+pub fn test_create_bigint_from_words(ctx: CallContext) -> Result<JsBigInt> {
   ctx
     .env
     .create_bigint_from_words(true, vec![u64::max_value(), u64::max_value()])
@@ -30,14 +30,14 @@ pub fn test_create_bigint_from_words(ctx: CallContext) -> Result<JsBigint> {
 
 #[js_function(1)]
 pub fn test_get_bigint_i64(ctx: CallContext) -> Result<JsNumber> {
-  let js_bigint = ctx.get::<JsBigint>(0)?;
+  let js_bigint = ctx.get::<JsBigInt>(0)?;
   let val = i64::try_from(js_bigint)?;
   ctx.env.create_int32(val as i32)
 }
 
 #[js_function(1)]
 pub fn test_get_bigint_u64(ctx: CallContext) -> Result<JsNumber> {
-  let js_bigint = ctx.get::<JsBigint>(0)?;
+  let js_bigint = ctx.get::<JsBigInt>(0)?;
   let val = u64::try_from(js_bigint)?;
   ctx.env.create_int32(val as i32)
 }

examples/napi/__test__/typegen.spec.ts.md

@@ -13,6 +13,9 @@ Generated by [AVA](https://avajs.dev).
     export function sumNums(nums: Array<number>): number␊
     export function readFileAsync(path: string): Promise<Buffer>␊
     export function asyncMultiTwo(arg: number): Promise<number>␊
+    export function bigintAdd(a: BigInt, b: BigInt): BigInt␊
+    export function createBigInt(): BigInt␊
+    export function createBigIntI64(): BigInt␊
     export function getCwd(callback: (arg0: string) => void): void␊
     export function readFile(callback: (arg0: Error | undefined, arg1: string | null) => void): void␊
     export function eitherStringOrNumber(input: string | number): number␊

examples/napi/__test__/values.spec.ts

@@ -35,6 +35,9 @@ import {
   withoutAbortController,
   withAbortController,
   asyncMultiTwo,
+  bigintAdd,
+  createBigInt,
+  createBigIntI64,
 } from '../'
 
 test('number', (t) => {
@@ -217,3 +220,17 @@ MaybeTest('abort resolved task', async (t) => {
   await withAbortController(1, 2, ctrl.signal).then(() => ctrl.abort())
   t.pass('should not throw')
 })
+
+const BigIntTest = typeof BigInt !== 'undefined' ? test : test.skip
+
+BigIntTest('BigInt add', (t) => {
+  t.is(bigintAdd(BigInt(1), BigInt(2)), BigInt(3))
+})
+
+BigIntTest('create BigInt', (t) => {
+  t.is(createBigInt(), BigInt('-3689348814741910323300'))
+})
+
+BigIntTest('create BigInt i64', (t) => {
+  t.is(createBigIntI64(), BigInt(100))
+})

examples/napi/index.d.ts

@@ -3,6 +3,9 @@ export function getNums(): Array<number>
 export function sumNums(nums: Array<number>): number
 export function readFileAsync(path: string): Promise<Buffer>
 export function asyncMultiTwo(arg: number): Promise<number>
+export function bigintAdd(a: BigInt, b: BigInt): BigInt
+export function createBigInt(): BigInt
+export function createBigIntI64(): BigInt
 export function getCwd(callback: (arg0: string) => void): void
 export function readFile(callback: (arg0: Error | undefined, arg1: string | null) => void): void
 export function eitherStringOrNumber(input: string | number): number

examples/napi/src/bigint.rs

@@ -0,0 +1,19 @@
+use napi::bindgen_prelude::*;
+
+#[napi]
+fn bigint_add(a: BigInt, b: BigInt) -> u128 {
+  a.get_u128().1 + b.get_u128().1
+}
+
+#[napi]
+fn create_big_int() -> BigInt {
+  BigInt {
+    words: vec![100u64, 200u64],
+    sign_bit: true,
+  }
+}
+
+#[napi]
+fn create_big_int_i64() -> i64n {
+  i64n(100)
+}

examples/napi/src/lib.rs

@@ -5,6 +5,7 @@ extern crate serde_derive;
 
 mod array;
 mod r#async;
+mod bigint;
 mod callback;
 mod class;
 mod class_factory;

examples/napi/tsconfig.json

@@ -4,7 +4,7 @@
   "compilerOptions": {
     "outDir": "./dist",
     "rootDir": "__test__",
-    "target": "ES2015"
+    "target": "ES2018"
   },
   "exclude": ["dist", "index.d.ts"]
 }