feat: add context info issuer layer for external function (#8832)

crates/node_binding/binding.d.ts

@@ -371,6 +371,7 @@ export declare function cleanupGlobalTrace(): void
 
 export interface ContextInfo {
   issuer: string
+  issuerLayer?: string
 }
 
 export declare function formatDiagnostic(diagnostic: JsDiagnostic): ExternalObject<'Diagnostic'>

crates/rspack_binding_values/src/raw_options/raw_external.rs

@@ -69,6 +69,7 @@ impl From<RawExternalItemFnResult> for ExternalItemFnResult {
 #[napi(object)]
 pub struct ContextInfo {
   pub issuer: String,
+  pub issuer_layer: Option<String>,
 }
 
 #[derive(Debug)]
@@ -120,6 +121,7 @@ impl From<ExternalItemFnCtx> for RawExternalItemFnCtx {
       context: value.context,
       context_info: ContextInfo {
         issuer: value.context_info.issuer,
+        issuer_layer: value.context_info.issuer_layer,
       },
       resolve_options_with_dependency_type: value.resolve_options_with_dependency_type,
       resolver_factory: value.resolver_factory,

crates/rspack_core/src/options/externals.rs

@@ -21,6 +21,7 @@ pub type ExternalItemObject = HashMap<String, ExternalItemValue>;
 
 pub struct ContextInfo {
   pub issuer: String,
+  pub issuer_layer: Option<String>,
 }
 
 pub struct ExternalItemFnCtx {

crates/rspack_plugin_externals/src/plugin.rs

@@ -180,7 +180,9 @@ async fn factorize(&self, data: &mut ModuleFactoryCreateData) -> Result<Option<B
             issuer: data
               .issuer
               .clone()
-              .map_or("".to_string(), |i| i.to_string()),
+              .map(|i| i.to_string())
+              .unwrap_or_default(),
+            issuer_layer: data.issuer_layer.clone(),
           },
           resolve_options_with_dependency_type: ResolveOptionsWithDependencyType {
             resolve_options: data

packages/rspack-test-tools/tests/configCases/externals/context-info/index.js

@@ -0,0 +1,7 @@
+import e1 from "external-pkg";
+import e2 from "./other-layer";
+
+it("should have the correct value", () => {
+  expect(e1).toBe(1);
+  expect(e2).toBe(2);
+});

packages/rspack-test-tools/tests/configCases/externals/context-info/other-layer.js

@@ -0,0 +1,3 @@
+import e2 from "external-pkg";
+
+export default e2;

packages/rspack-test-tools/tests/configCases/externals/context-info/rspack.config.js

@@ -0,0 +1,26 @@
+/** @type {import("@rspack/core").Configuration} */
+module.exports = {
+	entry: "./index.js",
+	module: {
+		rules: [
+			{
+				test: /other-layer\.js$/,
+				layer: "other-layer",
+			}
+		]
+	},
+	externals: [
+		function ({ context, request, contextInfo }, callback) {
+			if (request === "external-pkg") {
+				if (contextInfo.issuerLayer === "other-layer") {
+					return callback(null, "var 2");
+				}
+				return callback(null, "var 1");
+			}
+			return callback()
+		}
+	],
+	experiments: {
+		layers: true,
+	}
+};

packages/rspack/etc/core.api.md

@@ -1113,6 +1113,7 @@ export type Context = string;
 // @public (undocumented)
 type ContextInfo = {
     issuer: string;
+    issuerLayer?: string;
 };
 
 // @public (undocumented)

packages/rspack/src/Module.ts

@@ -25,6 +25,7 @@ export type ResourceDataWithData = ResourceData & {
 export type CreateData = Partial<JsCreateData>;
 export type ContextInfo = {
 	issuer: string;
+	issuerLayer?: string;
 };
 export type ResolveData = {
 	contextInfo: ContextInfo;

packages/rspack/src/builtin-plugin/ExternalsPlugin.ts

@@ -1,6 +1,7 @@
 import {
 	type BuiltinPlugin,
 	BuiltinPluginName,
+	type RawExternalItemFnCtx,
 	type RawExternalsPluginOptions
 } from "@rspack/binding";
 
@@ -44,7 +45,7 @@ function getRawExternalItem(
 	}
 
 	if (typeof item === "function") {
-		return async ctx => {
+		return async (ctx: RawExternalItemFnCtx) => {
 			return await new Promise((resolve, reject) => {
 				const data = ctx.data();
 				const promise = item(