fix(turbopack/transform_options): enforce default react runtime (#48400)

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### How?

Closes NEXT-
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### What?

This PR enforces turbopack uses `automatic` jsx runtime.

- closes WEB-901.

### Why?

If you set `ts|jsconfig`'s `jsx` to any custom value, you'll encounter
next.js message

```
The following mandatory changes were made to your tsconfig.json:

	- jsx was set to preserve (next.js implements its own optimized jsx transform)
```

Then internally transform sets jsx to use automatic runtime instead. In
case of turbopack, its transform pass is embedded so instead of setting
it to preserve falls back to automatic by default. PR doesn't handle
validations / or emitting user friendly messages yet, just enforce
runtime config regardless of how user sets it.

There maybe some additional followups to mimic exact transform existing
next.js does.

---------

Co-authored-by: Maia Teegarden <dev@padmaia.rocks>

packages/next-swc/crates/next-core/src/next_client/context.rs

@@ -158,7 +158,7 @@ pub async fn get_client_module_options_context(
     let tsconfig = get_typescript_transform_options(project_path);
     let decorators_options = get_decorators_transform_options(project_path);
     let mdx_rs_options = *next_config.mdx_rs().await?;
-    let jsx_runtime_options = get_jsx_transform_options(project_path, mdx_rs_options);
+    let jsx_runtime_options = get_jsx_transform_options(project_path);
     let enable_webpack_loaders = {
         let options = &*next_config.webpack_loaders_options().await?;
         let loaders_options = WebpackLoadersOptions {

packages/next-swc/crates/next-core/src/next_server/context.rs

@@ -235,7 +235,7 @@ pub async fn get_server_module_options_context(
     let tsconfig = get_typescript_transform_options(project_path);
     let decorators_options = get_decorators_transform_options(project_path);
     let mdx_rs_options = *next_config.mdx_rs().await?;
-    let jsx_runtime_options = get_jsx_transform_options(project_path, mdx_rs_options);
+    let jsx_runtime_options = get_jsx_transform_options(project_path);
     let enable_emotion = *get_emotion_compiler_config(next_config).await?;
     let enable_styled_components = *get_styled_components_compiler_config(next_config).await?;
 

packages/next-swc/crates/next-core/src/transform_options.rs

@@ -123,45 +123,33 @@ pub async fn get_decorators_transform_options(
 #[turbo_tasks::function]
 pub async fn get_jsx_transform_options(
     project_path: FileSystemPathVc,
-    is_mdx_rs_enabled: bool,
 ) -> Result<JsxTransformOptionsVc> {
     let tsconfig = get_typescript_options(project_path).await;
 
+    // [NOTE]: ref: WEB-901
+    // next.js does not allow to overriding react runtime config via tsconfig /
+    // jsconfig, it forces overrides into automatic runtime instead.
+    // [TODO]: we need to emit / validate config message like next.js devserver does
+    let react_transform_options = JsxTransformOptions {
+        import_source: None,
+        runtime: Some("automatic".to_string()),
+    };
+
     let react_transform_options = if let Some(tsconfig) = tsconfig {
         read_from_tsconfigs(&tsconfig, |json, _| {
             let jsx_import_source = json["compilerOptions"]["jsxImportSource"]
                 .as_str()
                 .map(|s| s.to_string());
 
-            // interop between tsconfig's jsx to swc's jsx runtime configuration. Swc's jsx
-            // runtime is a subset of tsconfig's jsx.
-            let runtime = if let Some(jsx_runtime) = json["compilerOptions"]["jsx"].as_str() {
-                match jsx_runtime {
-                    "react" => Some("classic".to_string()),
-                    "react-jsx" => Some("automatic".to_string()),
-                    "react-jsxdev" => Some("automatic".to_string()),
-                    _ => None,
-                }
-            } else {
-                None
-            };
-
             Some(JsxTransformOptions {
                 import_source: jsx_import_source,
-                runtime,
+                ..react_transform_options.clone()
             })
         })
         .await?
         .unwrap_or_default()
-    } else if is_mdx_rs_enabled {
-        // Mdx can implicitly includes jsx components, trying to enable jsx with default
-        // if jsx is not explicitly enabled
-        JsxTransformOptions {
-            import_source: None,
-            runtime: None,
-        }
     } else {
-        Default::default()
+        react_transform_options
     };
 
     Ok(react_transform_options.cell())