feat(transformer): add ESTarget (#7091)

closes #6982

crates/oxc_transformer/Cargo.toml

@@ -46,6 +46,7 @@ serde_json = { workspace = true }
 sha1 = { workspace = true }
 
 [dev-dependencies]
+insta = { workspace = true }
 oxc_codegen = { workspace = true }
 oxc_parser = { workspace = true }
 pico-args = { workspace = true }

crates/oxc_transformer/examples/transformer.rs

@@ -1,26 +1,27 @@
 #![allow(clippy::print_stdout)]
-use std::{env, path::Path};
+use std::{path::Path, str::FromStr};
 
 use oxc_allocator::Allocator;
 use oxc_codegen::CodeGenerator;
 use oxc_parser::Parser;
 use oxc_semantic::SemanticBuilder;
 use oxc_span::SourceType;
-use oxc_transformer::{TransformOptions, Transformer};
+use oxc_transformer::{ESTarget, TransformOptions, Transformer};
 use pico_args::Arguments;
 
 // Instruction:
-// create a `test.tsx`,
-// run `cargo run -p oxc_transformer --example transformer`
-// or `just watch "run -p oxc_transformer --example transformer"`
+// create a `test.js`,
+// run `just example transformer` or `just watch-example transformer`
 
 fn main() {
     let mut args = Arguments::from_env();
-    let name = env::args().nth(1).unwrap_or_else(|| "test.js".to_string());
     let targets: Option<String> = args.opt_value_from_str("--targets").unwrap_or(None);
+    let target: Option<String> = args.opt_value_from_str("--target").unwrap_or(None);
+    let name = args.free_from_str().unwrap_or_else(|_| "test.js".to_string());
 
     let path = Path::new(&name);
-    let source_text = std::fs::read_to_string(path).expect("{name} not found");
+    let source_text =
+        std::fs::read_to_string(path).unwrap_or_else(|err| panic!("{name} not found.\n{err}"));
     let allocator = Allocator::default();
     let source_type = SourceType::from_path(path).unwrap();
 
@@ -62,6 +63,8 @@ fn main() {
         // ..BabelEnvOptions::default()
         // })
         // .unwrap()
+    } else if let Some(target) = &target {
+        TransformOptions::from(ESTarget::from_str(target).unwrap())
     } else {
         TransformOptions::enable_all()
     };

crates/oxc_transformer/src/lib.rs

@@ -56,7 +56,7 @@ pub use crate::{
     jsx::{JsxOptions, JsxRuntime, ReactRefreshOptions},
     options::{
         babel::{BabelEnvOptions, BabelOptions, Targets},
-        EnvOptions, TransformOptions,
+        ESTarget, EnvOptions, TransformOptions,
     },
     plugins::*,
     typescript::{RewriteExtensionsMode, TypeScriptOptions},

crates/oxc_transformer/src/options/env.rs

@@ -1,3 +1,6 @@
+use std::str::FromStr;
+
+use cow_utils::CowUtils;
 use serde::Deserialize;
 
 use crate::{
@@ -14,6 +17,45 @@ use crate::{
 
 use super::babel::BabelEnvOptions;
 
+#[derive(Debug, Default, Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
+pub enum ESTarget {
+    ES5,
+    ES2015,
+    ES2016,
+    ES2017,
+    ES2018,
+    ES2019,
+    ES2020,
+    ES2021,
+    ES2022,
+    ES2023,
+    ES2024,
+    #[default]
+    ESNext,
+}
+
+impl FromStr for ESTarget {
+    type Err = String;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s.cow_to_lowercase().as_ref() {
+            "es5" => Ok(Self::ES5),
+            "es2015" => Ok(Self::ES2015),
+            "es2016" => Ok(Self::ES2016),
+            "es2017" => Ok(Self::ES2017),
+            "es2018" => Ok(Self::ES2018),
+            "es2019" => Ok(Self::ES2019),
+            "es2020" => Ok(Self::ES2020),
+            "es2021" => Ok(Self::ES2021),
+            "es2022" => Ok(Self::ES2022),
+            "es2023" => Ok(Self::ES2023),
+            "es2024" => Ok(Self::ES2024),
+            "esnext" => Ok(Self::ESNext),
+            _ => Err(format!("Invalid target \"{s}\".")),
+        }
+    }
+}
+
 #[derive(Debug, Default, Clone, Deserialize)]
 #[serde(try_from = "BabelEnvOptions")]
 pub struct EnvOptions {
@@ -46,10 +88,10 @@ impl EnvOptions {
             regexp: RegExpOptions {
                 sticky_flag: true,
                 unicode_flag: true,
+                unicode_property_escapes: true,
                 dot_all_flag: true,
-                look_behind_assertions: true,
                 named_capture_groups: true,
-                unicode_property_escapes: true,
+                look_behind_assertions: true,
                 match_indices: true,
                 set_notation: true,
             },
@@ -91,6 +133,40 @@ impl EnvOptions {
     }
 }
 
+impl From<ESTarget> for EnvOptions {
+    fn from(target: ESTarget) -> Self {
+        Self {
+            regexp: RegExpOptions {
+                sticky_flag: target < ESTarget::ES2015,
+                unicode_flag: target < ESTarget::ES2015,
+                unicode_property_escapes: target < ESTarget::ES2018,
+                dot_all_flag: target < ESTarget::ES2015,
+                named_capture_groups: target < ESTarget::ES2018,
+                look_behind_assertions: target < ESTarget::ES2018,
+                match_indices: target < ESTarget::ES2022,
+                set_notation: target < ESTarget::ES2024,
+            },
+            es2015: ES2015Options {
+                arrow_function: (target < ESTarget::ES2015).then(ArrowFunctionsOptions::default),
+            },
+            es2016: ES2016Options { exponentiation_operator: target < ESTarget::ES2016 },
+            es2017: ES2017Options { async_to_generator: target < ESTarget::ES2017 },
+            es2018: ES2018Options {
+                object_rest_spread: (target < ESTarget::ES2018)
+                    .then(ObjectRestSpreadOptions::default),
+                async_generator_functions: target < ESTarget::ES2018,
+            },
+            es2019: ES2019Options { optional_catch_binding: target < ESTarget::ES2019 },
+            es2020: ES2020Options { nullish_coalescing_operator: target < ESTarget::ES2020 },
+            es2021: ES2021Options { logical_assignment_operators: target < ESTarget::ES2021 },
+            es2022: ES2022Options {
+                class_static_block: target < ESTarget::ES2022,
+                class_properties: (target < ESTarget::ES2022).then(ClassPropertiesOptions::default),
+            },
+        }
+    }
+}
+
 impl TryFrom<BabelEnvOptions> for EnvOptions {
     type Error = String;
 
@@ -100,10 +176,10 @@ impl TryFrom<BabelEnvOptions> for EnvOptions {
             regexp: RegExpOptions {
                 sticky_flag: o.can_enable_plugin("transform-sticky-regex"),
                 unicode_flag: o.can_enable_plugin("transform-unicode-regex"),
+                unicode_property_escapes: o.can_enable_plugin("transform-unicode-property-regex"),
                 dot_all_flag: o.can_enable_plugin("transform-dotall-regex"),
-                look_behind_assertions: o.can_enable_plugin("esbuild-regexp-lookbehind-assertions"),
                 named_capture_groups: o.can_enable_plugin("transform-named-capturing-groups-regex"),
-                unicode_property_escapes: o.can_enable_plugin("transform-unicode-property-regex"),
+                look_behind_assertions: o.can_enable_plugin("esbuild-regexp-lookbehind-assertions"),
                 match_indices: o.can_enable_plugin("esbuild-regexp-match-indices"),
                 set_notation: o.can_enable_plugin("transform-unicode-sets-regex"),
             },

crates/oxc_transformer/src/options/mod.rs

@@ -5,8 +5,6 @@ use std::path::PathBuf;
 
 use oxc_diagnostics::Error;
 
-pub use env::EnvOptions;
-
 use crate::{
     common::helper_loader::{HelperLoaderMode, HelperLoaderOptions},
     compiler_assumptions::CompilerAssumptions,
@@ -24,6 +22,8 @@ use crate::{
     ReactRefreshOptions,
 };
 
+pub use env::{ESTarget, EnvOptions};
+
 use babel::BabelOptions;
 
 /// <https://babel.dev/docs/options>
@@ -79,6 +79,12 @@ impl TransformOptions {
     }
 }
 
+impl From<ESTarget> for TransformOptions {
+    fn from(target: ESTarget) -> Self {
+        Self { env: EnvOptions::from(target), ..Self::default() }
+    }
+}
+
 impl TryFrom<&BabelOptions> for TransformOptions {
     type Error = Vec<Error>;
 

crates/oxc_transformer/src/regexp/options.rs

@@ -1,26 +1,34 @@
 #[derive(Default, Debug, Clone, Copy)]
 pub struct RegExpOptions {
-    /// Enables plugin to transform the RegExp literal has `y` flag
+    /// Enables plugin to transform the RegExp literal with a `y` flag
+    /// ES2015 <https://babel.dev/docs/babel-plugin-transform-sticky-regex>
     pub sticky_flag: bool,
 
-    /// Enables plugin to transform the RegExp literal has `u` flag
+    /// Enables plugin to transform the RegExp literal with a `u` flag
+    /// ES2015 <https://babel.dev/docs/babel-plugin-transform-unicode-regex>
     pub unicode_flag: bool,
 
-    /// Enables plugin to transform the RegExp literal has `s` flag
-    pub dot_all_flag: bool,
+    /// Enables plugin to transform the RegExp literal that has `\p{}` and `\P{}` unicode property escapes
+    /// ES2018 <https://babel.dev/docs/babel-plugin-transform-unicode-property-regex>
+    pub unicode_property_escapes: bool,
 
-    /// Enables plugin to transform the RegExp literal has `(?<=)` or `(?<!)` lookbehind assertions
-    pub look_behind_assertions: bool,
+    /// Enables plugin to transform the RegExp literal with a `s` flag
+    /// ES2018 <https://babel.dev/docs/babel-plugin-transform-dotall-regex>
+    pub dot_all_flag: bool,
 
-    /// Enables plugin to transform the RegExp literal has `(?<name>x)` named capture groups
+    /// Enables plugin to transform the RegExp literal that has `(?<name>x)` named capture groups
+    /// ES2018 <https://babel.dev/docs/babel-plugin-transform-named-capturing-groups-regex>
     pub named_capture_groups: bool,
 
-    /// Enables plugin to transform the RegExp literal has `\p{}` and `\P{}` unicode property escapes
-    pub unicode_property_escapes: bool,
+    /// Enables plugin to transform the RegExp literal that has `(?<=)` or `(?<!)` lookbehind assertions
+    /// ES2018 <https://github.com/tc39/proposal-regexp-lookbehind>
+    pub look_behind_assertions: bool,
 
-    /// Enables plugin to transform `d` flag
+    /// Enables plugin to transform the `d` flag
+    /// ES2022 <https://github.com/tc39/proposal-regexp-match-indices>
     pub match_indices: bool,
 
-    /// Enables plugin to transform the RegExp literal has `v` flag
+    /// Enables plugin to transform the RegExp literal that has `v` flag
+    /// ES2024 <https://babel.dev/docs/babel-plugin-transform-unicode-sets-regex>
     pub set_notation: bool,
 }

crates/oxc_transformer/tests/es_target/mod.rs

@@ -0,0 +1,60 @@
+use std::{path::Path, str::FromStr};
+
+use oxc_allocator::Allocator;
+use oxc_codegen::{CodeGenerator, CodegenOptions};
+use oxc_parser::Parser;
+use oxc_semantic::SemanticBuilder;
+use oxc_span::SourceType;
+use oxc_transformer::{ESTarget, TransformOptions, Transformer};
+
+use crate::run;
+
+pub(crate) fn test(source_text: &str, target: &str) -> String {
+    let source_type = SourceType::default();
+    let allocator = Allocator::default();
+    let ret = Parser::new(&allocator, source_text, source_type).parse();
+    let mut program = ret.program;
+    let (symbols, scopes) =
+        SemanticBuilder::new().build(&program).semantic.into_symbol_table_and_scope_tree();
+    let options = TransformOptions::from(ESTarget::from_str(target).unwrap());
+    Transformer::new(&allocator, Path::new(""), options).build_with_symbols_and_scopes(
+        symbols,
+        scopes,
+        &mut program,
+    );
+    CodeGenerator::new()
+        .with_options(CodegenOptions { single_quote: true, ..CodegenOptions::default() })
+        .build(&program)
+        .code
+}
+
+#[test]
+fn es2015() {
+    use std::fmt::Write;
+
+    let cases = [
+        ("es5", "() => {}"),
+        ("es2015", "a ** b"),
+        ("es2016", "async function foo() {}"),
+        ("es2017", "({ ...x })"),
+        ("es2018", "try {} catch {}"),
+        ("es2019", "a ?? b"),
+        ("es2020", "a ||= b"),
+        ("es2021", "class foo { static {} }"),
+    ];
+
+    // Test no transformation for esnext.
+    for (_, case) in cases {
+        assert_eq!(run(case, SourceType::mjs()), test(case, "esnext"));
+    }
+
+    let snapshot = cases.iter().enumerate().fold(String::new(), |mut w, (i, (target, case))| {
+        let result = test(case, target);
+        write!(w, "########## {i} {target}\n{case}\n----------\n{result}\n").unwrap();
+        w
+    });
+
+    insta::with_settings!({ prepend_module_to_snapshot => false, snapshot_suffix => "", omit_expression => true }, {
+        insta::assert_snapshot!("es_target", snapshot);
+    });
+}

crates/oxc_transformer/tests/es_target/snapshots/es_target.snap

@@ -0,0 +1,54 @@
+---
+source: crates/oxc_transformer/tests/es_target/mod.rs
+snapshot_kind: text
+---
+########## 0 es5
+() => {}
+----------
+(function() {});
+
+########## 1 es2015
+a ** b
+----------
+Math.pow(a, b);
+
+########## 2 es2016
+async function foo() {}
+----------
+import _asyncToGenerator from '@babel/runtime/helpers/asyncToGenerator';
+function foo() {
+	return _foo.apply(this, arguments);
+}
+function _foo() {
+	_foo = _asyncToGenerator(function* () {});
+	return _foo.apply(this, arguments);
+}
+
+########## 3 es2017
+({ ...x })
+----------
+import _objectSpread from '@babel/runtime/helpers/objectSpread2';
+_objectSpread({}, x);
+
+########## 4 es2018
+try {} catch {}
+----------
+try {} catch (_unused) {}
+
+########## 5 es2019
+a ?? b
+----------
+var _a;
+(_a = a) !== null && _a !== void 0 ? _a : b;
+
+########## 6 es2020
+a ||= b
+----------
+a || (a = b);
+
+########## 7 es2021
+class foo { static {} }
+----------
+class foo {
+	static #_ = (() => {})();
+}

crates/oxc_transformer/tests/mod.rs

@@ -1 +1,16 @@
+mod es_target;
 mod plugins;
+
+use oxc_allocator::Allocator;
+use oxc_codegen::{CodeGenerator, CodegenOptions};
+use oxc_parser::Parser;
+use oxc_span::SourceType;
+
+pub fn run(source_text: &str, source_type: SourceType) -> String {
+    let allocator = Allocator::default();
+    let ret = Parser::new(&allocator, source_text, source_type).parse();
+    CodeGenerator::new()
+        .with_options(CodegenOptions { single_quote: true, ..CodegenOptions::default() })
+        .build(&ret.program)
+        .code
+}