Implement Promise Race

Author: komyg

nova_vm/src/ecmascript/builtins/control_abstraction_objects/promise_objects/promise_abstract_operations/promise_group_record.rs

@@ -23,11 +23,12 @@ use crate::{
     },
 };
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, Eq, PartialEq)]
 pub enum PromiseGroupType {
     All,
     AllSettled,
     Any,
+    Race,
 }
 
 #[derive(Debug, Clone, Copy)]
@@ -89,6 +90,14 @@ impl<'a> PromiseGroup<'a> {
                     self.reject(agent, index, value.unbind(), gc.reborrow());
                 }
             },
+            PromiseGroupType::Race => match reaction_type {
+                PromiseReactionType::Fulfill => {
+                    self.immediately_resolve(agent, value.unbind(), gc.reborrow());
+                }
+                PromiseReactionType::Reject => {
+                    self.immediately_reject(agent, value.unbind(), gc.nogc());
+                }
+            },
         }
     }
 

nova_vm/src/ecmascript/builtins/control_abstraction_objects/promise_objects/promise_constructor.rs

@@ -285,11 +285,11 @@ impl PromiseConstructor {
     /// > method.
     fn race<'gc>(
         agent: &mut Agent,
-        _this_value: Value,
-        _arguments: ArgumentsList,
+        this_value: Value,
+        arguments: ArgumentsList,
         gc: GcScope<'gc, '_>,
     ) -> JsResult<'gc, Value<'gc>> {
-        Err(agent.todo("Promise.race", gc.into_nogc()))
+        promise_group(agent, this_value, arguments, PromiseGroupType::Race, gc)
     }
 
     /// ### [27.2.4.6 Promise.reject ( r )](https://tc39.es/ecma262/#sec-promise.reject)
@@ -680,6 +680,7 @@ fn promise_group<'gc>(
 /// ### [27.2.4.1.2 PerformPromiseAll ( iteratorRecord, constructor, resultCapability, promiseResolve )](https://tc39.es/ecma262/#sec-performpromiseall)
 /// ### [27.2.4.2.1 PerformPromiseAllSettled ( iteratorRecord, constructor, resultCapability, promiseResolve )](https://tc39.es/ecma262/#sec-performpromiseallsettled)
 /// ### [27.2.4.3.1 PerformPromiseAny ( iteratorRecord, constructor, resultCapability, promiseResolve )](https://tc39.es/ecma262/#sec-performpromiseany)
+/// ### [27.2.4.5.1 PerformPromiseRace ( iteratorRecord, constructor, resultCapability, promiseResolve )](https://tc39.es/ecma262/#sec-performpromiserace)
 #[allow(clippy::too_many_arguments)]
 fn perform_promise_group<'gc>(
     agent: &mut Agent,
@@ -743,6 +744,10 @@ fn perform_promise_group<'gc>(
 
         // b. If next is done, then
         let Some(next) = next else {
+            if promise_group_type == PromiseGroupType::Race {
+                return Ok(promise.get(agent));
+            }
+
             *iterator_done = true;
             let promise_group = promise_group_reference.get(agent).bind(gc.nogc());
             let data = promise_group.get_mut(agent);