feat(transformer): add proposal-decorators (#2868)

crates/oxc_transformer/src/decorators/mod.rs

@@ -0,0 +1,19 @@
+use serde::Deserialize;
+
+/// Only `"2023-11"` will be implemented because Babel 8 will only support "2023-11" and "legacy".
+#[derive(Debug, Default, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct DecoratorsOptions;
+
+/// [proposal-decorators](https://babeljs.io/docs/babel-plugin-proposal-decorators)
+#[derive(Debug, Default)]
+pub struct Decorators {
+    #[allow(unused)]
+    options: DecoratorsOptions,
+}
+
+impl Decorators {
+    pub fn new(options: DecoratorsOptions) -> Self {
+        Self { options }
+    }
+}

crates/oxc_transformer/src/lib.rs

@@ -6,6 +6,7 @@
 //! * <https://github.com/microsoft/TypeScript/blob/main/src/compiler/transformer.ts>
 
 // Plugins: <https://babeljs.io/docs/plugins-list>
+mod decorators;
 mod react_display_name;
 mod react_jsx;
 mod react_jsx_self;
@@ -19,6 +20,7 @@ use oxc_semantic::Semantic;
 use oxc_span::SourceType;
 
 pub use crate::{
+    decorators::{Decorators, DecoratorsOptions},
     react_display_name::{ReactDisplayName, ReactDisplayNameOptions},
     react_jsx::{ReactJsx, ReactJsxOptions},
     react_jsx_self::{ReactJsxSelf, ReactJsxSelfOptions},
@@ -29,6 +31,7 @@ pub use crate::{
 #[allow(unused)]
 #[derive(Debug, Default, Clone)]
 pub struct TransformOptions {
+    pub decorators: DecoratorsOptions,
     pub typescript: TypeScriptOptions,
     pub react_jsx: ReactJsxOptions,
     pub react_display_name: ReactDisplayNameOptions,
@@ -43,6 +46,8 @@ pub struct Transformer<'a> {
     semantic: Semantic<'a>,
     options: TransformOptions,
 
+    // Stage 3
+    decorators: Decorators,
     // [preset-typescript](https://babeljs.io/docs/babel-preset-typescript)
     typescript: TypeScript,
     // [preset-react](https://babeljs.io/docs/babel-preset-react)
@@ -64,6 +69,7 @@ impl<'a> Transformer<'a> {
             source_type,
             semantic,
             options,
+            decorators: Decorators::default(),
             typescript: TypeScript::default(),
             react_display_name: ReactDisplayName::default(),
             react_jsx: ReactJsx::default(),

tasks/transform_conformance/src/test_case.rs

@@ -3,6 +3,9 @@ use std::{
     path::{Path, PathBuf},
 };
 
+use serde::de::DeserializeOwned;
+use serde_json::Value;
+
 use oxc_allocator::Allocator;
 use oxc_codegen::{Codegen, CodegenOptions};
 use oxc_diagnostics::Error;
@@ -11,11 +14,9 @@ use oxc_semantic::SemanticBuilder;
 use oxc_span::{SourceType, VALID_EXTENSIONS};
 use oxc_tasks_common::{normalize_path, print_diff_in_terminal, BabelOptions};
 use oxc_transformer::{
-    ReactDisplayNameOptions, ReactJsxOptions, ReactJsxSelfOptions, ReactJsxSourceOptions,
-    TransformOptions, Transformer, TypeScriptOptions,
+    DecoratorsOptions, ReactDisplayNameOptions, ReactJsxOptions, ReactJsxSelfOptions,
+    ReactJsxSourceOptions, TransformOptions, Transformer, TypeScriptOptions,
 };
-use serde::de::DeserializeOwned;
-use serde_json::Value;
 
 use crate::{fixture_root, root, TestRunnerEnv};
 
@@ -86,6 +87,10 @@ pub trait TestCase {
         }
         let options = self.options();
         TransformOptions {
+            decorators: options
+                .get_plugin("proposal-decorators")
+                .map(get_options::<DecoratorsOptions>)
+                .unwrap_or_default(),
             typescript: options
                 .get_plugin("transform-typescript")
                 .map(get_options::<TypeScriptOptions>)