From 4855f2d9d2658f15fe80d353b7ee835df548f1be Mon Sep 17 00:00:00 2001
From: 9aoy <gaoyuan.1226@bytedance.com>
Date: Fri, 24 Jan 2025 16:06:12 +0800
Subject: [PATCH] feat: support for `resolve` and `context` in `api.transform`
 (#4426)

---
 packages/core/src/loader/transformLoader.ts | 2 ++
 packages/core/src/types/plugin.ts           | 9 +++++++++
 website/docs/en/plugins/dev/core.mdx        | 4 ++++
 website/docs/zh/plugins/dev/core.mdx        | 4 ++++
 4 files changed, 19 insertions(+)

diff --git a/packages/core/src/loader/transformLoader.ts b/packages/core/src/loader/transformLoader.ts
index 4b30a353d2..61b53728ec 100644
--- a/packages/core/src/loader/transformLoader.ts
+++ b/packages/core/src/loader/transformLoader.ts
@@ -26,6 +26,7 @@ export default async function transform(
 
   const result = await transform({
     code: source,
+    context: this.context,
     resource: this.resource,
     resourcePath: this.resourcePath,
     resourceQuery: this.resourceQuery,
@@ -33,6 +34,7 @@ export default async function transform(
     addDependency: this.addDependency.bind(this),
     emitFile: this.emitFile.bind(this),
     importModule: this.importModule.bind(this),
+    resolve: this.resolve.bind(this),
   });
 
   if (result === null || result === undefined) {
diff --git a/packages/core/src/types/plugin.ts b/packages/core/src/types/plugin.ts
index 65dc6f3b3c..c36eb33927 100644
--- a/packages/core/src/types/plugin.ts
+++ b/packages/core/src/types/plugin.ts
@@ -231,6 +231,11 @@ export type TransformContext = {
    * The code of the module.
    */
   code: string;
+  /**
+   * The directory path of the currently processed module,
+   * which changes with the location of each processed module.
+   */
+  context: string | null;
   /**
    * The absolute path of the module, including the query.
    * @example '/home/user/project/src/index.js?foo=123'
@@ -268,6 +273,10 @@ export type TransformContext = {
    * Compile and execute a module at the build time.
    */
   importModule: Rspack.LoaderContext['importModule'];
+  /**
+   * Resolve a module specifier.
+   */
+  resolve: Rspack.LoaderContext['resolve'];
 };
 
 export type TransformHandler = (
diff --git a/website/docs/en/plugins/dev/core.mdx b/website/docs/en/plugins/dev/core.mdx
index c268050f1b..6191e5ba5e 100644
--- a/website/docs/en/plugins/dev/core.mdx
+++ b/website/docs/en/plugins/dev/core.mdx
@@ -274,6 +274,7 @@ The handler param is a transformation function that takes the current module cod
 ```ts
 type TransformContext = {
   code: string;
+  context: string | null;
   resource: string;
   resourcePath: string;
   resourceQuery: string;
@@ -281,6 +282,7 @@ type TransformContext = {
   addDependency: (file: string) => void;
   emitFile: Rspack.LoaderContext['emitFile'];
   importModule: Rspack.LoaderContext['importModule'];
+  resolve: Rspack.LoaderContext['resolve'];
 };
 
 type TransformResult =
@@ -298,6 +300,8 @@ type TransformHandler = (
 The `handler` function provides the following params:
 
 - `code`: The code of the module.
+- `context`: The directory path of the currently processed module. The same as Rspack loader's [this.context](https://rspack.dev/api/loader-api/context#thiscontext).
+- `resolve`: Resolve a module specifier. The same as Rspack loader's [this.resolve](https://rspack.dev/api/loader-api/context#thisresolve).
 - `resource`: The absolute path of the module, including the query.
 - `resourcePath`: The absolute path of the module, without the query.
 - `resourceQuery`: The query of the module.
diff --git a/website/docs/zh/plugins/dev/core.mdx b/website/docs/zh/plugins/dev/core.mdx
index 3f683b87f2..095facb4f1 100644
--- a/website/docs/zh/plugins/dev/core.mdx
+++ b/website/docs/zh/plugins/dev/core.mdx
@@ -272,6 +272,7 @@ handler 参数是一个转换函数，接收模块当前的代码，并返回转
 ```ts
 type TransformContext = {
   code: string;
+  context: string | null;
   resource: string;
   resourcePath: string;
   resourceQuery: string;
@@ -279,6 +280,7 @@ type TransformContext = {
   addDependency: (file: string) => void;
   emitFile: Rspack.LoaderContext['emitFile'];
   importModule: Rspack.LoaderContext['importModule'];
+  resolve: Rspack.LoaderContext['resolve'];
 };
 
 type TransformResult =
@@ -296,6 +298,8 @@ type TransformHandler = (
 handler 函数提供以下参数：
 
 - `code`：模块的代码。
+- `context`：当前被处理的模块所在的目录路径。与 Rspack loader 的 [this.context](https://rspack.dev/zh/api/loader-api/context#thiscontext) 相同。
+- `resolve`：解析一个模块标识符。与 Rspack loader 的 [this.resolve](https://rspack.dev/zh/api/loader-api/context#thisresolve) 相同。
 - `resource`：模块的绝对路径，包含 query。
 - `resourcePath`：模块的绝对路径，不包含 query。
 - `resourceQuery`：模块路径上的 query。