fix(napi): improve napi_adjust_external_memory (#17501)

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2 files changed, 37 insertions, 0 deletions

diff --git a/test_napi/src/lib.rs b/test_napi/src/lib.rs
index 78a8248dc..71258ee7f 100644
--- a/test_napi/src/lib.rs
+++ b/test_napi/src/lib.rs
@@ -13,6 +13,7 @@ pub mod callback;
 pub mod coerce;
 pub mod date;
 pub mod error;
+pub mod mem;
 pub mod numbers;
 pub mod object_wrap;
 pub mod primitives;
@@ -152,6 +153,8 @@ unsafe extern "C" fn napi_register_module_v1(
   r#async::init(env, exports);
   date::init(env, exports);
   tsfn::init(env, exports);
+  mem::init(env, exports);
+
   init_cleanup_hook(env, exports);
 
   exports
diff --git a/test_napi/src/mem.rs b/test_napi/src/mem.rs
new file mode 100644
index 000000000..dde4418cb
--- /dev/null
+++ b/test_napi/src/mem.rs
@@ -0,0 +1,34 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+
+use crate::assert_napi_ok;
+use crate::napi_new_property;
+use napi_sys::*;
+use std::ptr;
+
+extern "C" fn adjust_external_memory(
+  env: napi_env,
+  _: napi_callback_info,
+) -> napi_value {
+  let mut adjusted_value = 0;
+
+  assert_napi_ok!(napi_adjust_external_memory(env, 1024, &mut adjusted_value));
+
+  let mut result = ptr::null_mut();
+  assert_napi_ok!(napi_create_int64(env, adjusted_value, &mut result));
+  result
+}
+
+pub fn init(env: napi_env, exports: napi_value) {
+  let properties = &[napi_new_property!(
+    env,
+    "adjust_external_memory",
+    adjust_external_memory
+  )];
+
+  assert_napi_ok!(napi_define_properties(
+    env,
+    exports,
+    properties.len(),
+    properties.as_ptr()
+  ));
+}