Promise await{1,6}

4 files changed, 87 insertions, 2 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index be86f89..21931e8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,9 +4,10 @@
 
 - The `javascript` module was created with the `TypeOf`, and `Symbol` types, and
   `find_symbol`, `make_reference`, `set_reference`, `update_reference`,
-  `dereference` and `type_of` functions.
+  `dereference`, and `type_of` functions.
 - The `javascript/array` module was created with the `Array(element)` type and
   `to_list`, `from_list`, `map`, `fold`, `fold_right`, `get`, and `length`
   functions.
 - The `javascript/promise` module was created with the `Promise(value)` type and
-  `rescue`, `resolve`, `tap`, `map_try`, `map`, `then_try` and `then` functions.
+  `rescue`, `resolve`, `tap`, `map_try`, `map`, `then_try`, `await{2,6}` and
+  `then` functions.
diff --git a/src/ffi.js b/src/ffi.js
index d7b6bf9..07649e9 100644
--- a/src/ffi.js
+++ b/src/ffi.js
@@ -118,3 +118,7 @@ export function set_reference(ref, value) {
   ref.value = value;
   return previous;
 }
+
+export function all_promises(...promises) {
+  return Promise.all(promises);
+}
diff --git a/src/gleam/javascript/promise.gleam b/src/gleam/javascript/promise.gleam
index 3c7190c..5e374dd 100644
--- a/src/gleam/javascript/promise.gleam
+++ b/src/gleam/javascript/promise.gleam
@@ -49,3 +49,40 @@ pub fn then_try(
     }
   })
 }
+
+pub external fn await2(Promise(a), Promise(b)) -> Promise(#(a, b)) =
+  "../../ffi.js" "all_promises"
+
+pub external fn await3(
+  Promise(a),
+  Promise(b),
+  Promise(c),
+) -> Promise(#(a, b, c)) =
+  "../../ffi.js" "all_promises"
+
+pub external fn await4(
+  Promise(a),
+  Promise(b),
+  Promise(c),
+  Promise(d),
+) -> Promise(#(a, b, c, d)) =
+  "../../ffi.js" "all_promises"
+
+pub external fn await5(
+  Promise(a),
+  Promise(b),
+  Promise(c),
+  Promise(d),
+  Promise(e),
+) -> Promise(#(a, b, c, d, e)) =
+  "../../ffi.js" "all_promises"
+
+pub external fn await6(
+  Promise(a),
+  Promise(b),
+  Promise(c),
+  Promise(d),
+  Promise(e),
+  Promise(f),
+) -> Promise(#(a, b, c, d, e, f)) =
+  "../../ffi.js" "all_promises"
diff --git a/test/gleam/javascript/promise_test.gleam b/test/gleam/javascript/promise_test.gleam
index c77cd5a..942abcc 100644
--- a/test/gleam/javascript/promise_test.gleam
+++ b/test/gleam/javascript/promise_test.gleam
@@ -84,3 +84,46 @@ pub fn rescue_poisoned_test() {
   |> promise.rescue(fn(_) { 100 })
   |> promise.tap(fn(a) { assert 100 = a })
 }
+
+pub fn await2_test() {
+  promise.await2(promise.resolve(1), promise.resolve(3))
+  |> promise.tap(fn(x) { assert #(1, 3) = x })
+}
+
+pub fn await3_test() {
+  promise.await3(promise.resolve(1), promise.resolve(3), promise.resolve(4))
+  |> promise.tap(fn(x) { assert #(1, 3, 4) = x })
+}
+
+pub fn await4_test() {
+  promise.await4(
+    promise.resolve(1),
+    promise.resolve(3),
+    promise.resolve(4),
+    promise.resolve(6),
+  )
+  |> promise.tap(fn(x) { assert #(1, 3, 4, 6) = x })
+}
+
+pub fn await5_test() {
+  promise.await5(
+    promise.resolve(1),
+    promise.resolve(3),
+    promise.resolve(4),
+    promise.resolve(6),
+    promise.resolve(10),
+  )
+  |> promise.tap(fn(x) { assert #(1, 3, 4, 6, 10) = x })
+}
+
+pub fn await6_test() {
+  promise.await6(
+    promise.resolve(1),
+    promise.resolve(3),
+    promise.resolve(4),
+    promise.resolve(6),
+    promise.resolve(10),
+    promise.resolve(13),
+  )
+  |> promise.tap(fn(x) { assert #(1, 3, 4, 6, 10, 13) = x })
+}