node_api 0.5.0

Write Node.js native addons with Node-API in Rust.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132

use crate::{
	sys::{
		napi_create_array, napi_get_array_length, napi_get_element, napi_set_element, napi_status,
	},
	Env, Error, Result, Value,
};
use num::ToPrimitive;
use std::mem::MaybeUninit;

#[derive(Clone, Copy)]
pub struct Array<'a>(Value<'a>);

impl<'a> Array<'a> {
	pub(crate) fn from_value(value: Value) -> Array {
		Array(value)
	}

	pub fn value(&self) -> Value<'a> {
		self.0
	}

	pub fn env(&self) -> Env<'a> {
		self.0.env()
	}

	pub fn new(env: Env) -> Result<Array> {
		let value = unsafe {
			let mut result = MaybeUninit::uninit();
			let status = napi_create_array(env.raw(), result.as_mut_ptr());
			if status != napi_status::napi_ok {
				return Err(Error::from_last_node_api_error(env.raw(), status));
			}
			result.assume_init()
		};
		Ok(Array(Value::from_raw(env, value)))
	}

	pub fn size(&self) -> Result<usize> {
		let len = unsafe {
			let mut result = MaybeUninit::uninit();
			let status =
				napi_get_array_length(self.env().raw(), self.value().raw(), result.as_mut_ptr());
			if status != napi_status::napi_ok {
				return Err(Error::from_last_node_api_error(self.env().raw(), status));
			}
			result.assume_init()
		};
		let len = len
			.to_usize()
			.ok_or_else(|| Error::message("could not cast array length to usize"))?;
		Ok(len)
	}

	pub fn get(&self, index: usize) -> Result<Value<'a>> {
		let index = index
			.to_u32()
			.ok_or_else(|| Error::message("could not cast index to u32"))?;
		let value = unsafe {
			let mut result = MaybeUninit::uninit();
			let status = napi_get_element(
				self.env().raw(),
				self.value().raw(),
				index,
				result.as_mut_ptr(),
			);
			if status != napi_status::napi_ok {
				return Err(Error::from_last_node_api_error(self.env().raw(), status));
			}
			result.assume_init()
		};
		let value = Value::from_raw(self.env(), value);
		Ok(value)
	}

	pub fn set(&mut self, index: usize, value: impl Into<Value<'a>>) -> Result<()> {
		let index = index
			.to_u32()
			.ok_or_else(|| Error::message("could not cast index to u32"))?;
		let value = value.into();
		unsafe {
			let status = napi_set_element(self.env().raw(), self.value().raw(), index, value.raw());
			if status != napi_status::napi_ok {
				return Err(Error::from_last_node_api_error(self.env().raw(), status));
			}
		}
		Ok(())
	}

	pub fn push(&mut self, value: impl Into<Value<'a>>) -> Result<()> {
		let len = self.size()?;
		self.set(len, value)?;
		Ok(())
	}

	pub fn iter(&self) -> Result<ArrayIterator<'a>> {
		Ok(ArrayIterator {
			array: *self,
			len: self.size()?,
			i: 0,
		})
	}
}

pub struct ArrayIterator<'a> {
	array: Array<'a>,
	len: usize,
	i: usize,
}

impl<'a> ArrayIterator<'a> {
	pub fn is_empty(&self) -> bool {
		self.len == 0
	}

	pub fn len(&self) -> usize {
		self.len
	}
}

impl<'a> Iterator for ArrayIterator<'a> {
	type Item = Result<Value<'a>>;

	fn next(&mut self) -> Option<Self::Item> {
		if self.i >= self.len {
			None
		} else {
			let result = self.array.get(self.i);
			self.i += 1;
			Some(result)
		}
	}
}