feat(transformer): implement react-jsx-self (#2946)

crates/oxc_ast/src/ast/jsx.rs

@@ -227,6 +227,12 @@ pub struct JSXIdentifier<'a> {
     pub name: Atom<'a>,
 }
 
+impl<'a> JSXIdentifier<'a> {
+    pub fn new(span: Span, name: Atom<'a>) -> Self {
+        Self { span, name }
+    }
+}
+
 // 1.4 JSX Children
 
 /// JSX Child

crates/oxc_transformer/src/lib.rs

@@ -122,4 +122,9 @@ impl<'a> VisitMut<'a> for Transformer<'a> {
         self.x1_react.transform_export_default_declaration(decl);
         walk_mut::walk_export_default_declaration_mut(self, decl);
     }
+
+    fn visit_jsx_opening_element(&mut self, elem: &mut JSXOpeningElement<'a>) {
+        self.x1_react.transform_jsx_opening_element(elem);
+        walk_mut::walk_jsx_opening_element_mut(self, elem);
+    }
 }

crates/oxc_transformer/src/react/jsx_self/mod.rs

@@ -1,5 +1,8 @@
 use std::rc::Rc;
 
+use oxc_ast::ast::*;
+use oxc_span::SPAN;
+
 use crate::context::Ctx;
 
 /// [plugin-transform-react-jsx-self](https://babeljs.io/docs/babel-plugin-transform-react-jsx-self)
@@ -10,13 +13,46 @@ use crate::context::Ctx;
 ///
 /// In: `<sometag />`
 /// Out: `<sometag __self={this} />`
+///
+/// TODO:
+/// *. Omit adding `this` in some conditions
+///    <https://github.com/babel/babel/blob/9cd048b5ad45eafd157c4f9968343e36170a66c1/packages/babel-plugin-transform-react-jsx-self/src/index.ts#L78>
 #[allow(unused)]
 pub struct ReactJsxSelf<'a> {
+    development: bool,
+
     ctx: Ctx<'a>,
 }
 
 impl<'a> ReactJsxSelf<'a> {
-    pub fn new(ctx: &Ctx<'a>) -> Self {
+    pub fn new(development: bool, ctx: &Ctx<'a>) -> Self {
-        Self { ctx: Rc::clone(ctx) }
+        Self { development, ctx: Rc::clone(ctx) }
+    }
+
+    pub fn transform_jsx_opening_element(&self, elem: &mut JSXOpeningElement<'a>) {
+        if self.development {
+            self.add_self_this_attribute(elem);
+        }
+    }
+}
+
+impl<'a> ReactJsxSelf<'a> {
+    /// `<div __self={this} />`
+    ///       ^^^^^^^^^^^^^
+    fn add_self_this_attribute(&self, elem: &mut JSXOpeningElement<'a>) {
+        let name = {
+            let name = self.ctx.ast.new_atom("__self");
+            JSXAttributeName::Identifier(JSXIdentifier::new(SPAN, name))
+        };
+        let value = {
+            let jsx_expr = JSXExpression::Expression(self.ctx.ast.this_expression(SPAN));
+            let container = self.ctx.ast.jsx_expression_container(SPAN, jsx_expr);
+            JSXAttributeValue::ExpressionContainer(container)
+        };
+        let attribute = {
+            let attribute = self.ctx.ast.jsx_attribute(SPAN, name, Some(value));
+            JSXAttributeItem::Attribute(attribute)
+        };
+        elem.attributes.push(attribute);
     }
 }

crates/oxc_transformer/src/react/mod.rs

@@ -35,10 +35,11 @@ pub struct React<'a> {
 // Constructors
 impl<'a> React<'a> {
     pub fn new(options: ReactOptions, ctx: &Ctx<'a>) -> Self {
+        let development = options.development;
         Self {
             ctx: Rc::clone(ctx),
             jsx: ReactJsx::new(options, ctx),
-            jsx_self: ReactJsxSelf::new(ctx),
+            jsx_self: ReactJsxSelf::new(development, ctx),
             jsx_source: ReactJsxSource::new(ctx),
             display_name: ReactDisplayName::new(ctx),
         }
@@ -76,4 +77,8 @@ impl<'a> React<'a> {
     ) {
         self.display_name.transform_export_default_declaration(decl);
     }
+
+    pub fn transform_jsx_opening_element(&mut self, elem: &mut JSXOpeningElement<'a>) {
+        self.jsx_self.transform_jsx_opening_element(elem);
+    }
 }

tasks/transform_conformance/babel.snap.md

@@ -1,4 +1,4 @@
-Passed: 75/174
+Passed: 76/177
 
 # All Passed:
 
@@ -107,3 +107,7 @@ Passed: 75/174
 # babel-plugin-transform-react-display-name (15/16)
 * display-name/nested/input.js
 
+# babel-plugin-transform-react-jsx-self (1/3)
+* react-source/arrow-function/input.js
+* react-source/disable-with-super/input.js
+

tasks/transform_conformance/src/lib.rs

@@ -94,6 +94,7 @@ const CASES: &[&str] = &[
     // React
     // "babel-plugin-transform-react-jsx",
     "babel-plugin-transform-react-display-name",
+    "babel-plugin-transform-react-jsx-self",
     // // Proposal
     // "babel-plugin-proposal-decorators",
 ];