feat(transformer): add compiler assumptions (#2872)

closes #2869

crates/oxc_syntax/src/assumptions.rs

@@ -1,15 +0,0 @@
-#[cfg(feature = "serialize")]
-use serde::Deserialize;
-
-/// Compiler assumptions
-///
-/// See <https://babeljs.io/docs/assumptions>
-#[derive(Debug, Default, Clone, Copy)]
-#[cfg_attr(feature = "serialize", derive(Deserialize))]
-#[cfg_attr(feature = "serialize", serde(rename_all = "camelCase"))]
-pub struct CompilerAssumptions {
-    /// When using operators that check for null or undefined, assume that they are never used with the special value document.all.
-    /// See <https://babeljs.io/docs/assumptions#nodocumentall>.
-    #[cfg_attr(feature = "serialize", serde(default))]
-    pub no_document_all: bool,
-}

crates/oxc_syntax/src/lib.rs

@@ -1,6 +1,5 @@
 //! Common code for JavaScript Syntax
 
-pub mod assumptions;
 pub mod class;
 pub mod identifier;
 pub mod keyword;

crates/oxc_transformer/src/compiler_assumptions.rs

@@ -0,0 +1,34 @@
+use serde::Deserialize;
+
+/// Compiler assumptions
+///
+/// For producing smaller output.
+///
+/// See <https://babeljs.io/docs/assumptions>
+#[derive(Debug, Default, Clone, Copy, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct CompilerAssumptions {
+    pub array_like_is_iterable: bool,
+    pub constant_reexports: bool,
+    pub constant_super: bool,
+    pub enumerable_module_meta: bool,
+    pub ignore_function_length: bool,
+    pub ignore_to_primitive_hint: bool,
+    pub iterable_is_array: bool,
+    pub mutable_template_object: bool,
+    pub no_class_calls: bool,
+    pub no_document_all: bool,
+    pub no_incomplete_ns_import_detection: bool,
+    pub no_new_arrows: bool,
+    pub no_uninitialized_private_field_access: bool,
+    pub object_rest_no_symbols: bool,
+    pub private_fields_as_symbols: bool,
+    pub private_fields_as_properties: bool,
+    pub pure_getters: bool,
+    pub set_class_methods: bool,
+    pub set_computed_properties: bool,
+    pub set_public_class_fields: bool,
+    pub set_spread_properties: bool,
+    pub skip_for_of_iterator_closing: bool,
+    pub super_is_callable_constructor: bool,
+}

crates/oxc_transformer/src/lib.rs

@@ -5,6 +5,8 @@
 //! * <https://babel.dev/docs/presets>
 //! * <https://github.com/microsoft/TypeScript/blob/main/src/compiler/transformer.ts>
 
+// Core
+mod compiler_assumptions;
 // Plugins: <https://babeljs.io/docs/plugins-list>
 mod decorators;
 mod react_display_name;
@@ -20,6 +22,7 @@ use oxc_semantic::Semantic;
 use oxc_span::SourceType;
 
 pub use crate::{
+    compiler_assumptions::CompilerAssumptions,
     decorators::{Decorators, DecoratorsOptions},
     react_display_name::{ReactDisplayName, ReactDisplayNameOptions},
     react_jsx::{ReactJsx, ReactJsxOptions},
@@ -31,6 +34,12 @@ pub use crate::{
 #[allow(unused)]
 #[derive(Debug, Default, Clone)]
 pub struct TransformOptions {
+    // Core
+    /// Set assumptions in order to produce smaller output.
+    /// For more information, check the [assumptions](https://babel.dev/docs/assumptions) documentation page.
+    pub assumptions: CompilerAssumptions,
+
+    // Plugins
     pub decorators: DecoratorsOptions,
     pub typescript: TypeScriptOptions,
     pub react_jsx: ReactJsxOptions,

crates/oxc_transformer/src/react_jsx/mod.rs

@@ -1,8 +1,6 @@
-use serde::Deserialize;
+mod options;
 
-#[derive(Debug, Default, Clone, Deserialize)]
+pub use self::options::ReactJsxOptions;
-#[serde(rename_all = "camelCase")]
-pub struct ReactJsxOptions;
 
 /// [plugin-transform-react-jsx](https://babeljs.io/docs/babel-plugin-transform-react-jsx)
 ///
@@ -12,6 +10,11 @@ pub struct ReactJsxOptions;
 /// please use @babel/plugin-transform-react-jsx-development for a better debugging experience.
 ///
 /// This plugin is included in `preset-react`.
+///
+/// References:
+///
+/// * <https://babeljs.io/docs/babel-plugin-transform-react-jsx>
+/// * <https://github.com/babel/babel/tree/main/packages/babel-helper-builder-react-jsx>
 #[derive(Debug, Default)]
 pub struct ReactJsx {
     #[allow(unused)]

crates/oxc_transformer/src/react_jsx/options.rs

@@ -0,0 +1,97 @@
+use std::borrow::Cow;
+
+use serde::Deserialize;
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ReactJsxOptions {
+    // Both Runtimes
+    //
+    /// Decides which runtime to use.
+    pub runtime: ReactJsxRuntime,
+
+    /// This toggles behavior specific to development, such as adding __source and __self.
+    ///
+    /// Defaults to `true`.
+    #[serde(default = "default_as_true")]
+    pub development: bool,
+
+    /// Enables `@babel/plugin-transform-react-pure-annotations`.
+    ///
+    /// It will mark top-level React method calls as pure for tree shaking.
+    ///
+    /// Defaults to `true`.
+    #[serde(default = "default_as_true")]
+    pub pure: bool,
+    //
+    // React Automatic Runtime
+    //
+    /// Replaces the import source when importing functions.
+    ///
+    /// Defaults to `react`.
+    #[serde(default = "default_for_import_source")]
+    pub import_source: Cow<'static, str>,
+    //
+    // React Classic Runtime
+    //
+    /// Replace the function used when compiling JSX expressions.
+    ///
+    /// It should be a qualified name (e.g. React.createElement) or an identifier (e.g. createElement).
+    ///
+    /// Note that the @jsx React.DOM pragma has been deprecated as of React v0.12
+    ///
+    /// Defaults to `React.createElement`.
+    #[serde(default = "default_for_pragma")]
+    pub pragma: Cow<'static, str>,
+
+    /// Replace the component used when compiling JSX fragments. It should be a valid JSX tag name.
+    ///
+    /// Defaults to `React.Fragment`.
+    #[serde(default = "default_for_pragma_frag")]
+    pub pragma_frag: Cow<'static, str>,
+    //
+    // `useBuiltIns` and `useSpread` are deprecated in babel 8.
+}
+
+impl Default for ReactJsxOptions {
+    fn default() -> Self {
+        Self {
+            runtime: ReactJsxRuntime::default(),
+            development: default_as_true(),
+            pure: default_as_true(),
+            import_source: default_for_import_source(),
+            pragma: default_for_pragma(),
+            pragma_frag: default_for_pragma_frag(),
+        }
+    }
+}
+
+#[inline]
+fn default_as_true() -> bool {
+    true
+}
+
+#[inline]
+fn default_for_import_source() -> Cow<'static, str> {
+    Cow::Borrowed("react")
+}
+
+fn default_for_pragma() -> Cow<'static, str> {
+    Cow::Borrowed("React.createElement")
+}
+
+fn default_for_pragma_frag() -> Cow<'static, str> {
+    Cow::Borrowed("React.Fragment")
+}
+
+/// Decides which runtime to use.
+///
+/// Auto imports the functions that JSX transpiles to.
+/// classic does not automatic import anything.
+#[derive(Debug, Default, Clone, Deserialize)]
+pub enum ReactJsxRuntime {
+    Classic,
+    /// The default runtime is switched to automatic in Babel 8.
+    #[default]
+    Automatic,
+}

tasks/common/src/babel.rs

@@ -1,6 +1,5 @@
 use std::path::Path;
 
-use oxc_syntax::assumptions::CompilerAssumptions;
 use serde::Deserialize;
 use serde_json::Value;
 
@@ -21,7 +20,7 @@ pub struct BabelOptions {
     #[serde(default)]
     pub allow_undeclared_exports: bool,
     #[serde(default)]
-    pub assumptions: CompilerAssumptions,
+    pub assumptions: Value,
 }
 
 impl BabelOptions {

tasks/transform_conformance/src/test_case.rs

@@ -87,6 +87,7 @@ pub trait TestCase {
         }
         let options = self.options();
         TransformOptions {
+            assumptions: serde_json::from_value(options.assumptions.clone()).unwrap_or_default(),
             decorators: options
                 .get_plugin("proposal-decorators")
                 .map(get_options::<DecoratorsOptions>)