5 files changed, 52 insertions, 4 deletions
diff --git a/cli/napi/js_native_api.rs b/cli/napi/js_native_api.rs
index 32f4b787e..07b583beb 100644
--- a/cli/napi/js_native_api.rs
+++ b/cli/napi/js_native_api.rs
@@ -1798,9 +1798,7 @@ fn napi_is_detached_arraybuffer(
 ) -> Result {
   let value = transmute::<napi_value, v8::Local<v8::Value>>(value);
   let _ab = v8::Local::<v8::ArrayBuffer>::try_from(value).unwrap();
-  // TODO: what is API for checking if ArrayBuffer is detached?
-  // there's only is_detachable I could find.
-  *result = false;
+  *result = _ab.was_detached();
   Ok(())
 }
 
diff --git a/test_napi/Cargo.toml b/test_napi/Cargo.toml
index 09faa4175..407275563 100644
--- a/test_napi/Cargo.toml
+++ b/test_napi/Cargo.toml
@@ -11,7 +11,7 @@ publish = false
 crate-type = ["cdylib"]
 
 [dependencies]
-napi-sys = { version = "2.2.2", default-features = false, features = ["napi4"] }
+napi-sys = { version = "2.2.2", default-features = false, features = ["napi7"] }
 
 [dev-dependencies]
 test_util = { path = "../test_util" }
diff --git a/test_napi/arraybuffer_test.js b/test_napi/arraybuffer_test.js
new file mode 100644
index 000000000..577443e8b
--- /dev/null
+++ b/test_napi/arraybuffer_test.js
@@ -0,0 +1,12 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+import { assertEquals, loadTestLibrary } from "./common.js";
+
+const typedarray = loadTestLibrary();
+
+Deno.test("napi arraybuffer detach", function () {
+  const buf = new ArrayBuffer(5);
+  assertEquals(buf.byteLength, 5);
+  typedarray.test_detached(buf);
+  assertEquals(buf.byteLength, 0);
+});
diff --git a/test_napi/src/arraybuffer.rs b/test_napi/src/arraybuffer.rs
new file mode 100644
index 000000000..cf170e713
--- /dev/null
+++ b/test_napi/src/arraybuffer.rs
@@ -0,0 +1,36 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use napi_sys::Status::napi_ok;
+use napi_sys::*;
+use std::ptr;
+
+extern "C" fn test_detached(
+  env: napi_env,
+  info: napi_callback_info,
+) -> napi_value {
+  let (args, argc, _) = crate::get_callback_info!(env, info, 1);
+  assert_eq!(argc, 1);
+
+  let mut value = false;
+  assert!(
+    unsafe { napi_is_detached_arraybuffer(env, args[0], &mut value) }
+      == napi_ok
+  );
+  assert!(!value);
+  assert!(unsafe { napi_detach_arraybuffer(env, args[0]) } == napi_ok);
+  assert!(
+    unsafe { napi_is_detached_arraybuffer(env, args[0], &mut value) }
+      == napi_ok
+  );
+  assert!(value);
+  args[0]
+}
+
+pub fn init(env: napi_env, exports: napi_value) {
+  let properties =
+    &[crate::new_property!(env, "test_detached\0", test_detached)];
+
+  unsafe {
+    napi_define_properties(env, exports, properties.len(), properties.as_ptr())
+  };
+}
diff --git a/test_napi/src/lib.rs b/test_napi/src/lib.rs
index 569256a0b..c1a13f6e4 100644
--- a/test_napi/src/lib.rs
+++ b/test_napi/src/lib.rs
@@ -5,6 +5,7 @@
 use napi_sys::*;
 
 pub mod array;
+pub mod arraybuffer;
 pub mod r#async;
 pub mod callback;
 pub mod coerce;
@@ -67,6 +68,7 @@ unsafe extern "C" fn napi_register_module_v1(
   strings::init(env, exports);
   numbers::init(env, exports);
   typedarray::init(env, exports);
+  arraybuffer::init(env, exports);
   array::init(env, exports);
   primitives::init(env, exports);
   properties::init(env, exports);