feat(neon): Add neon::types::JsMap

crates/neon/src/prelude.rs

@@ -9,7 +9,7 @@ pub use crate::{
     types::{
         boxed::{Finalize, JsBox},
         JsArray, JsArrayBuffer, JsBigInt64Array, JsBigUint64Array, JsBoolean, JsBuffer, JsError,
-        JsFloat32Array, JsFloat64Array, JsFunction, JsInt16Array, JsInt32Array, JsInt8Array,
+        JsFloat32Array, JsFloat64Array, JsFunction, JsInt16Array, JsInt32Array, JsInt8Array, JsMap,
         JsNull, JsNumber, JsObject, JsPromise, JsString, JsTypedArray, JsUint16Array,
         JsUint32Array, JsUint8Array, JsUndefined, JsValue, Value,
     },

crates/neon/src/sys/bindings/functions.rs

@@ -51,6 +51,9 @@ mod napi1 {
 
             fn close_handle_scope(env: Env, scope: HandleScope) -> Status;
 
+            fn instanceof(env: Env, object: Value, constructor: Value, result: *mut bool)
+                -> Status;
+
             fn is_arraybuffer(env: Env, value: Value, result: *mut bool) -> Status;
             fn is_typedarray(env: Env, value: Value, result: *mut bool) -> Status;
             fn is_buffer(env: Env, value: Value, result: *mut bool) -> Status;

crates/neon/src/sys/tag.rs

@@ -1,3 +1,5 @@
+use crate::sys;
+
 use super::{
     bindings as napi,
     raw::{Env, Local},
@@ -137,3 +139,37 @@ pub unsafe fn check_object_type_tag(env: Env, object: Local, tag: &super::TypeTa
 pub unsafe fn is_bigint(env: Env, val: Local) -> bool {
     is_type(env, val, napi::ValueType::BigInt)
 }
+
+pub unsafe fn is_map(env: Env, val: Local) -> bool {
+    let global_object = unsafe {
+        let mut out: super::raw::Local = std::mem::zeroed();
+        super::scope::get_global(env, &mut out);
+        out
+    };
+
+    let map_literal = {
+        let mut out: super::raw::Local = std::mem::zeroed();
+        let literal = b"Map";
+        assert_eq!(
+            super::string::new(&mut out, env, literal.as_ptr(), literal.len() as _),
+            true
+        );
+        out
+    };
+
+    let map_constructor = {
+        let mut out: super::raw::Local = std::mem::zeroed();
+        assert_eq!(
+            sys::object::get(&mut out, env, global_object, map_literal),
+            true
+        );
+        out
+    };
+
+    let mut result = false;
+    assert_eq!(
+        napi::instanceof(env, val, map_constructor, &mut result),
+        napi::Status::Ok
+    );
+    result
+}

crates/neon/src/types_impl/map.rs

@@ -0,0 +1,163 @@
+use std::{error, fmt, mem::MaybeUninit};
+
+use crate::{
+    context::{internal::Env, Context},
+    handle::{internal::TransparentNoCopyWrapper, root::NapiRef, Handle},
+    macro_internal::NeonResultTag,
+    object::Object,
+    result::{JsResult, NeonResult, ResultExt},
+    sys::{self, raw},
+    types::{private, JsFunction, JsObject, Value},
+};
+
+use super::{JsBoolean, JsNumber, JsUndefined};
+
+#[derive(Debug)]
+#[repr(transparent)]
+/// The type of JavaScript
+/// [`Map`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map)
+/// objects.
+pub struct JsMap(raw::Local);
+
+impl JsMap {
+    pub fn new<'cx, C>(cx: &mut C) -> NeonResult<Handle<'cx, Self>>
+    where
+        C: Context<'cx>,
+    {
+        let map = cx
+            .global::<JsFunction>("Map")?
+            .construct_with(cx)
+            .apply::<JsObject, _>(cx)?;
+
+        Ok(map.downcast_or_throw(cx)?)
+    }
+
+    pub fn size<'a, C: Context<'a>>(&self, cx: &mut C) -> NeonResult<Handle<'a, JsNumber>> {
+        Object::get(self, cx, "size")
+    }
+
+    // TODO: is the return type important here ?
+    // I see three possibilities here:
+    // 1. Stick to the JS and return the `undefined` (this is what we do now)
+    // 2. Check we get an `undefined` and return `Ok(())`
+    // 3. Just discard the return value and return `Ok(())`
+    // Solutions 2 & 3 are more user-friendly, but make more assumptions (though it
+    // should be fine given `Map` is not expected to be overridden ?).
+    pub fn clear<'a, C: Context<'a>>(&self, cx: &mut C) -> NeonResult<Handle<'a, JsUndefined>> {
+        Object::call_method_with(self, cx, "clear")?.apply(cx)
+    }
+
+    pub fn delete<'a, C: Context<'a>, K: Value>(
+        &self,
+        cx: &mut C,
+        key: Handle<'a, K>,
+    ) -> NeonResult<bool> {
+        Object::call_method_with(self, cx, "delete")?
+            .arg(key)
+            .apply::<JsBoolean, _>(cx)
+            .map(|v| v.value(cx))
+    }
+
+    pub fn entries<'a, C: Context<'a>>(&self, cx: &mut C) -> NeonResult<Handle<'a, JsObject>> {
+        Object::call_method_with(self, cx, "entries")?.apply(cx)
+    }
+
+    pub fn for_each<'a, C: Context<'a>, F: Value>(
+        &self,
+        cx: &mut C,
+        cb: Handle<'a, F>,
+    ) -> NeonResult<Handle<'a, JsUndefined>> {
+        Object::call_method_with(self, cx, "forEach")?
+            .arg(cb)
+            .apply(cx)
+    }
+
+    pub fn get<'a, C: Context<'a>, K: Value, R: Value>(
+        &self,
+        cx: &mut C,
+        key: Handle<'a, K>,
+    ) -> NeonResult<Handle<'a, R>> {
+        Object::call_method_with(self, cx, "get")?
+            .arg(key)
+            .apply(cx)
+    }
+
+    pub fn has<'a, C: Context<'a>, K: Value>(
+        &self,
+        cx: &mut C,
+        key: Handle<'a, K>,
+    ) -> NeonResult<bool> {
+        Object::call_method_with(self, cx, "has")?
+            .arg(key)
+            .apply::<JsBoolean, _>(cx)
+            .map(|v| v.value(cx))
+    }
+
+    pub fn keys<'a, C: Context<'a>, R: Value>(&self, cx: &mut C) -> NeonResult<Handle<'a, R>> {
+        Object::call_method_with(self, cx, "keys")?.apply(cx)
+    }
+
+    pub fn set<'a, C: Context<'a>, K: Value, V: Value>(
+        &self,
+        cx: &mut C,
+        key: Handle<'a, K>,
+        value: Handle<'a, V>,
+    ) -> NeonResult<Handle<'a, JsMap>> {
+        Object::call_method_with(self, cx, "set")?
+            .arg(key)
+            .arg(value)
+            .apply(cx)
+    }
+
+    pub fn values<'a, C: Context<'a>, R: Value>(&self, cx: &mut C) -> NeonResult<Handle<'a, R>> {
+        Object::call_method_with(self, cx, "values")?.apply(cx)
+    }
+
+    pub fn group_by<'a, C: Context<'a>, A: Value, B: Value, R: Value>(
+        cx: &mut C,
+        elements: Handle<'a, A>,
+        cb: Handle<'a, B>,
+    ) -> NeonResult<Handle<'a, R>> {
+        // TODO: This is broken and leads to a `failed to downcast any to object` error
+        // when trying to downcast `Map.groupBy` into a `JsFunction`...
+        cx.global::<JsObject>("Map")?
+            .call_method_with(cx, "groupBy")?
+            .arg(elements)
+            .arg(cb)
+            .apply(cx)
+    }
+
+    // TODO: should we implementd those as well ?
+    // Map[Symbol.species]
+    // Map.prototype[Symbol.iterator]()
+}
+
+unsafe impl TransparentNoCopyWrapper for JsMap {
+    type Inner = raw::Local;
+
+    fn into_inner(self) -> Self::Inner {
+        self.0
+    }
+}
+
+impl private::ValueInternal for JsMap {
+    fn name() -> &'static str {
+        "Map"
+    }
+
+    fn is_typeof<Other: Value>(env: Env, other: &Other) -> bool {
+        unsafe { sys::tag::is_map(env.to_raw(), other.to_local()) }
+    }
+
+    fn to_local(&self) -> raw::Local {
+        self.0
+    }
+
+    unsafe fn from_local(_env: Env, h: raw::Local) -> Self {
+        Self(h)
+    }
+}
+
+impl Value for JsMap {}
+
+impl Object for JsMap {}

crates/neon/src/types_impl/mod.rs

@@ -10,6 +10,7 @@ pub(crate) mod date;
 pub(crate) mod error;
 pub mod extract;
 pub mod function;
+pub(crate) mod map;
 pub(crate) mod promise;
 
 pub(crate) mod private;
@@ -47,6 +48,7 @@ pub use self::{
         JsUint8Array,
     },
     error::JsError,
+    map::JsMap,
     promise::{Deferred, JsPromise},
 };
 

test/napi/lib/map.js

@@ -0,0 +1,151 @@
+var addon = require("..");
+var assert = require("chai").assert;
+
+describe("JsMap", function () {
+  it("return a JsMap built in Rust", function () {
+    assert.deepEqual(new Map(), addon.return_js_map());
+  });
+
+  it("return a JsMap with a number as keys and values", function () {
+    assert.deepEqual(
+      new Map([
+        [1, 1000],
+        [-1, -1000],
+      ]),
+      addon.return_js_map_with_number_as_keys_and_values()
+    );
+  });
+
+  it("return a JsMap with heterogeneous keys/values", function () {
+    assert.deepEqual(
+      new Map([
+        ["a", 1],
+        [26, "z"],
+      ]),
+      addon.return_js_map_with_heterogeneous_keys_and_values()
+    );
+  });
+
+  it("can read from a JsMap", function () {
+    const map = new Map([
+      [1, "a"],
+      [2, "b"],
+    ]);
+    assert.strictEqual(addon.read_js_map(map, 2), "b");
+  });
+
+  it("can get size from a JsMap", function () {
+    const map = new Map([
+      [1, "a"],
+      [2, "b"],
+    ]);
+    assert.strictEqual(addon.get_js_map_size(map), 2);
+    assert.strictEqual(addon.get_js_map_size(new Map()), 0);
+  });
+
+  it("can modify a JsMap", function () {
+    const map = new Map([[1, "a"]]);
+    addon.modify_js_map(map, 2, "b");
+    assert.deepEqual(
+      map,
+      new Map([
+        [1, "a"],
+        [2, "b"],
+      ])
+    );
+  });
+
+  it("returns undefined when accessing outside JsMap bounds", function () {
+    assert.strictEqual(addon.read_js_map(new Map(), "x"), undefined);
+  });
+
+  it("can clear a JsMap", function () {
+    const map = new Map([[1, "a"]]);
+    addon.clear_js_map(map);
+    assert.deepEqual(map, new Map());
+  });
+
+  it("can delete key from JsMap", function () {
+    const map = new Map([
+      [1, "a"],
+      ["z", 26],
+    ]);
+
+    assert.strictEqual(addon.delete_js_map(map, "unknown"), false);
+    assert.deepEqual(
+      map,
+      new Map([
+        [1, "a"],
+        ["z", 26],
+      ])
+    );
+
+    assert.strictEqual(addon.delete_js_map(map, 1), true);
+    assert.deepEqual(map, new Map([["z", 26]]));
+
+    assert.strictEqual(addon.delete_js_map(map, "z"), true);
+    assert.deepEqual(map, new Map());
+  });
+
+  it("can use `has` on JsMap", function () {
+    const map = new Map([
+      [1, "a"],
+      ["z", 26],
+    ]);
+
+    assert.strictEqual(addon.has_js_map(map, 1), true);
+    assert.strictEqual(addon.has_js_map(map, "z"), true);
+    assert.strictEqual(addon.has_js_map(map, "unknown"), false);
+  });
+
+  it("can use `forEach` on JsMap", function () {
+    const map = new Map([
+      [1, "a"],
+      ["z", 26],
+    ]);
+    const collected = [];
+
+    assert.strictEqual(
+      addon.for_each_js_map(map, (value, key, map) => {
+        collected.push([key, value, map]);
+      }),
+      undefined
+    );
+
+    assert.deepEqual(collected, [
+      [1, "a", map],
+      ["z", 26, map],
+    ]);
+  });
+
+  it("can use `groupBy` on JsMap", function () {
+    const inventory = [
+      { name: "asparagus", type: "vegetables", quantity: 9 },
+      { name: "bananas", type: "fruit", quantity: 5 },
+      { name: "goat", type: "meat", quantity: 23 },
+      { name: "cherries", type: "fruit", quantity: 12 },
+      { name: "fish", type: "meat", quantity: 22 },
+    ];
+
+    const restock = { restock: true };
+    const sufficient = { restock: false };
+    const result = addon.group_by_js_map(inventory, ({ quantity }) =>
+      quantity < 6 ? restock : sufficient
+    );
+    assert.deepEqual(
+      result,
+      new Map([
+        [restock, [{ name: "bananas", type: "fruit", quantity: 5 }]],
+        [
+          sufficient,
+          [
+            { name: "asparagus", type: "vegetables", quantity: 9 },
+            { name: "goat", type: "meat", quantity: 23 },
+            { name: "cherries", type: "fruit", quantity: 12 },
+            { name: "fish", type: "meat", quantity: 22 },
+          ],
+        ],
+      ])
+    );
+  });
+});