feat: add experimental Env::get_module_file_name method (#1783)

crates/napi/Cargo.toml

@@ -20,15 +20,15 @@ all-features = true
 independent = true
 
 [features]
-noop = []
 async = ["tokio_rt"]
+chrono_date = ["chrono", "napi5"]
 compat-mode = []
 default = ["napi3", "compat-mode"]                                               # for most Node.js users
+deferred_trace = ["napi4"]
+error_anyhow = ["anyhow"]
 experimental = ["napi-sys/experimental"]
-chrono_date = ["chrono", "napi5"]
 full = ["latin1", "napi9", "async", "serde-json", "experimental", "chrono_date"]
 latin1 = ["encoding_rs"]
-error_anyhow = ["anyhow"]
 napi1 = []
 napi2 = ["napi1", "napi-sys/napi2"]
 napi3 = ["napi2", "napi-sys/napi3"]
@@ -37,7 +37,8 @@ napi5 = ["napi4", "napi-sys/napi5"]
 napi6 = ["napi5", "napi-sys/napi6"]
 napi7 = ["napi6", "napi-sys/napi7"]
 napi8 = ["napi7", "napi-sys/napi8"]
-napi9 = ["napi8", "napi-sys/napi9"]
+napi9 = ["napi8", "napi-sys/napi9", "byteorder"]
+noop = []
 serde-json = ["serde", "serde_json"]
 tokio_fs = ["tokio/fs"]
 tokio_full = ["tokio/full"]
@@ -52,20 +53,19 @@ tokio_stats = ["tokio/stats"]
 tokio_sync = ["tokio/sync"]
 tokio_test_util = ["tokio/test-util"]
 tokio_time = ["tokio/time"]
-deferred_trace = ["napi4"]
 
 [dependencies]
+bitflags = "2"
 ctor = "0.2"
 once_cell = "1.16"
-bitflags = "2"
 
 [dependencies.anyhow]
-version = "1"
 optional = true
+version = "1"
 
 [dependencies.napi-sys]
-version = "2.2.3"
 path = "../sys"
+version = "2.2.3"
 
 [dependencies.encoding_rs]
 optional = true
@@ -75,9 +75,13 @@ version = "0.8"
 optional = true
 version = "0.4"
 
+[dependencies.byteorder]
+optional = true
+version = "1.5"
+
 [target.'cfg(target_os = "wasi")'.dependencies]
-tokio = { version = "1", optional = true, features = ["rt", "sync"] }
 napi-derive = { path = "../macro", version = "2.10.1", default-features = false }
+tokio = { version = "1", optional = true, features = ["rt", "sync"] }
 
 [target.'cfg(not(target_os = "wasi"))'.dependencies]
 tokio = { version = "1", optional = true, features = [

crates/napi/src/env.rs

@@ -1269,6 +1269,36 @@ impl Env {
     Ok(unsafe { JsSymbol::from_raw_unchecked(self.0, result) })
   }
 
+  #[cfg(feature = "napi9")]
+  /// This API retrieves the file path of the currently running JS module as a URL. For a file on
+  /// the local file system it will start with `file://`.
+  ///
+  /// # Errors
+  ///
+  /// The retrieved string may be empty if the add-on loading process fails to establish the
+  /// add-on's file name.
+  pub fn get_module_file_name(&self) -> Result<String> {
+    let mut char_ptr = ptr::null();
+    check_status!(
+      unsafe { sys::node_api_get_module_file_name(self.0, &mut char_ptr) },
+      "call node_api_get_module_file_name failed"
+    )?;
+    // SAFETY: This is safe because `char_ptr` is guaranteed to not be `null`, and point to
+    // null-terminated string data.
+    let module_filename = unsafe { std::ffi::CStr::from_ptr(char_ptr) };
+    #[cfg(windows)]
+    {
+      let byte_len = module_filename.to_bytes().len();
+      let mut utf16_buf = vec![0u16; byte_len / 2];
+      byteorder::LittleEndian::read_u16_into(module_filename.to_bytes(), &mut utf16_buf);
+      Ok(String::from_utf16_lossy(utf16_buf))
+    }
+    #[cfg(not(windows))]
+    {
+      Ok(module_filename.to_string_lossy().into_owned())
+    }
+  }
+
   /// ### Serialize `Rust Struct` into `JavaScript Value`
   ///
   /// ```