From ce861507cd8cac7c6d9e410f4e09373cdd87ef22 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 21:38:12 +0800
Subject: [PATCH 1/9] feat(transformer): Shorthand Properties

---
 crates/oxc_transformer/src/es2015/mod.rs      |  3 ++
 .../src/es2015/shorthand_properties.rs        | 37 +++++++++++++++++++
 crates/oxc_transformer/src/lib.rs             | 11 ++++++
 3 files changed, 51 insertions(+)
 create mode 100644 crates/oxc_transformer/src/es2015/mod.rs
 create mode 100644 crates/oxc_transformer/src/es2015/shorthand_properties.rs

diff --git a/crates/oxc_transformer/src/es2015/mod.rs b/crates/oxc_transformer/src/es2015/mod.rs
new file mode 100644
index 0000000000000..7ff2ccadb763f
--- /dev/null
+++ b/crates/oxc_transformer/src/es2015/mod.rs
@@ -0,0 +1,3 @@
+mod shorthand_properties;
+
+pub use shorthand_properties::ShorthandProperties;
diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
new file mode 100644
index 0000000000000..a8dfd0a59667e
--- /dev/null
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -0,0 +1,37 @@
+use oxc_ast::{ast::*, AstBuilder};
+use oxc_span::GetSpan;
+
+use std::rc::Rc;
+
+/// ES2015: Shorthand Properties
+///
+/// References:
+/// * <https://babel.dev/docs/babel-plugin-transform-shorthand-properties>
+/// * <https://github.com/babel/babel/blob/main/packages/babel-plugin-transform-shorthand-properties>
+pub struct ShorthandProperties<'a> {
+    ast: Rc<AstBuilder<'a>>,
+}
+
+impl<'a> ShorthandProperties<'a> {
+    pub fn new(ast: Rc<AstBuilder<'a>>) -> Self {
+        Self { ast }
+    }
+
+    pub fn transform_object_property<'b>(&mut self, obj_prop: &'b mut ObjectProperty<'a>) {
+        if obj_prop.shorthand {
+            obj_prop.shorthand = false;
+
+            if obj_prop.key.is_specific_id("__proto__") {
+                debug_assert!(
+                    !obj_prop.computed,
+                    "shorthand and computed cannot be true at the same time"
+                );
+                obj_prop.computed = true;
+
+                let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };
+                let expr = self.ast.literal_string_expression(proto);
+                obj_prop.key = PropertyKey::Expression(expr);
+            }
+        }
+    }
+}
diff --git a/crates/oxc_transformer/src/lib.rs b/crates/oxc_transformer/src/lib.rs
index b771e9f9e94d4..94a34042d54d5 100644
--- a/crates/oxc_transformer/src/lib.rs
+++ b/crates/oxc_transformer/src/lib.rs
@@ -7,6 +7,7 @@
 //! * <https://babel.dev/docs/presets>
 //! * <https://github.com/microsoft/TypeScript/blob/main/src/compiler/transformer.ts>
 
+mod es2015;
 mod es2016;
 mod es2019;
 mod es2021;
@@ -19,6 +20,7 @@ use oxc_ast::{ast::*, AstBuilder, VisitMut};
 use oxc_span::SourceType;
 use std::rc::Rc;
 
+use es2015::ShorthandProperties;
 use es2016::ExponentiationOperator;
 use es2019::OptionalCatchBinding;
 use es2021::LogicalAssignmentOperators;
@@ -39,6 +41,8 @@ pub struct Transformer<'a> {
     es2019_optional_catch_binding: Option<OptionalCatchBinding<'a>>,
     // es2016
     es2016_exponentiation_operator: Option<ExponentiationOperator<'a>>,
+    // es2015
+    es2015_shorthand_properties: Option<ShorthandProperties<'a>>,
 }
 
 impl<'a> Transformer<'a> {
@@ -66,6 +70,9 @@ impl<'a> Transformer<'a> {
         if options.target < TransformTarget::ES2016 {
             t.es2016_exponentiation_operator.replace(ExponentiationOperator::new(Rc::clone(&ast)));
         }
+        if options.target < TransformTarget::ES2015 {
+            t.es2015_shorthand_properties.replace(ShorthandProperties::new(Rc::clone(&ast)));
+        }
         t
     }
 
@@ -92,4 +99,8 @@ impl<'a, 'b> VisitMut<'a, 'b> for Transformer<'a> {
         }
         self.visit_statements(&mut clause.body.body);
     }
+
+    fn visit_object_property(&mut self, prop: &'b mut ObjectProperty<'a>) {
+        self.es2015_shorthand_properties.as_mut().map(|t| t.transform_object_property(prop));
+    }
 }

From 1ceaaed6b751640bffe1522c10ed2314e7f223d1 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 22:15:01 +0800
Subject: [PATCH 2/9] fix: visit children of `ObjectProperty`

---
 crates/oxc_transformer/src/lib.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/crates/oxc_transformer/src/lib.rs b/crates/oxc_transformer/src/lib.rs
index 94a34042d54d5..ca941a6d03be9 100644
--- a/crates/oxc_transformer/src/lib.rs
+++ b/crates/oxc_transformer/src/lib.rs
@@ -102,5 +102,11 @@ impl<'a, 'b> VisitMut<'a, 'b> for Transformer<'a> {
 
     fn visit_object_property(&mut self, prop: &'b mut ObjectProperty<'a>) {
         self.es2015_shorthand_properties.as_mut().map(|t| t.transform_object_property(prop));
+
+        self.visit_property_key(&mut prop.key);
+        self.visit_expression(&mut prop.value);
+        if let Some(init) = &mut prop.init {
+            self.visit_expression(init);
+        }
     }
 }

From de2dcfded886ba157685ea398c350885aab8b617 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 22:19:26 +0800
Subject: [PATCH 3/9] chore: early return, less nested

---
 .../src/es2015/shorthand_properties.rs        | 29 ++++++++++---------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index a8dfd0a59667e..b82c1775b7447 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -18,20 +18,21 @@ impl<'a> ShorthandProperties<'a> {
     }
 
     pub fn transform_object_property<'b>(&mut self, obj_prop: &'b mut ObjectProperty<'a>) {
-        if obj_prop.shorthand {
-            obj_prop.shorthand = false;
-
-            if obj_prop.key.is_specific_id("__proto__") {
-                debug_assert!(
-                    !obj_prop.computed,
-                    "shorthand and computed cannot be true at the same time"
-                );
-                obj_prop.computed = true;
-
-                let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };
-                let expr = self.ast.literal_string_expression(proto);
-                obj_prop.key = PropertyKey::Expression(expr);
-            }
+        if !obj_prop.shorthand {
+            return;
         }
+
+        obj_prop.shorthand = false;
+
+        if !obj_prop.key.is_specific_id("__proto__") {
+            return;
+        }
+
+        debug_assert!(!obj_prop.computed, "shorthand and computed cannot be true at the same time");
+        obj_prop.computed = true;
+
+        let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };
+        let expr = self.ast.literal_string_expression(proto);
+        obj_prop.key = PropertyKey::Expression(expr);
     }
 }

From c81faebb51db1f0cad69561504931513954c4bdb Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 22:52:01 +0800
Subject: [PATCH 4/9] fix: `shorthand` of method

---
 crates/oxc_transformer/src/es2015/shorthand_properties.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index b82c1775b7447..e8a3181e49fa6 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -18,17 +18,17 @@ impl<'a> ShorthandProperties<'a> {
     }
 
     pub fn transform_object_property<'b>(&mut self, obj_prop: &'b mut ObjectProperty<'a>) {
-        if !obj_prop.shorthand {
+        if !obj_prop.shorthand && !obj_prop.method {
             return;
         }
 
         obj_prop.shorthand = false;
+        obj_prop.method = false;
 
-        if !obj_prop.key.is_specific_id("__proto__") {
+        if !obj_prop.key.is_specific_id("__proto__") || obj_prop.computed {
             return;
         }
 
-        debug_assert!(!obj_prop.computed, "shorthand and computed cannot be true at the same time");
         obj_prop.computed = true;
 
         let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };

From c42656633bd0a3a5f48c39e552d293344f19e958 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 23:16:35 +0800
Subject: [PATCH 5/9] fix: handle string literal of `__proto__`

---
 crates/oxc_ast/src/ast/js.rs                              | 7 +++++++
 crates/oxc_transformer/src/es2015/shorthand_properties.rs | 8 +++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/crates/oxc_ast/src/ast/js.rs b/crates/oxc_ast/src/ast/js.rs
index 394ed08cac265..14bbe1adf5ded 100644
--- a/crates/oxc_ast/src/ast/js.rs
+++ b/crates/oxc_ast/src/ast/js.rs
@@ -420,6 +420,13 @@ impl<'a> PropertyKey<'a> {
             _ => false,
         }
     }
+
+    pub fn is_specific_string_literal(&self, string: &str) -> bool {
+        match self {
+            PropertyKey::Expression(expr) => expr.is_specific_string_literal(string),
+            _ => false,
+        }
+    }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index e8a3181e49fa6..50e20186bcc8c 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -25,7 +25,13 @@ impl<'a> ShorthandProperties<'a> {
         obj_prop.shorthand = false;
         obj_prop.method = false;
 
-        if !obj_prop.key.is_specific_id("__proto__") || obj_prop.computed {
+        if obj_prop.computed {
+            return;
+        }
+
+        if !obj_prop.key.is_specific_id("__proto__")
+            && !obj_prop.key.is_specific_string_literal("__proto__")
+        {
             return;
         }
 

From cf7fe6fd38fa23baafea89dad6c46ec997f1d348 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Fri, 6 Oct 2023 23:24:12 +0800
Subject: [PATCH 6/9] chore: early return for `"__proto__"() {}`

---
 .../src/es2015/shorthand_properties.rs            | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index 50e20186bcc8c..392f9f2ab41b6 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -29,14 +29,23 @@ impl<'a> ShorthandProperties<'a> {
             return;
         }
 
-        if !obj_prop.key.is_specific_id("__proto__")
-            && !obj_prop.key.is_specific_string_literal("__proto__")
-        {
+        let is_proto_id = obj_prop.key.is_specific_id("__proto__");
+        let is_proto_string = obj_prop.key.is_specific_string_literal("__proto__");
+
+        if !is_proto_id && !is_proto_string {
             return;
         }
 
         obj_prop.computed = true;
 
+        if is_proto_string {
+            // input:
+            // "__proto__"() {}
+            // output:
+            // ["__proto__"]: function() {}
+            return;
+        }
+
         let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };
         let expr = self.ast.literal_string_expression(proto);
         obj_prop.key = PropertyKey::Expression(expr);

From 52481268ff77a38da64d3e0089e9d1bf5980e21d Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Sat, 7 Oct 2023 14:28:39 +0800
Subject: [PATCH 7/9] chore: add test results

---
 crates/oxc_transformer/src/options.rs     |  1 +
 tasks/transform_conformance/babel.snap.md | 11 ++++++++++-
 tasks/transform_conformance/src/lib.rs    |  6 ++++--
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/crates/oxc_transformer/src/options.rs b/crates/oxc_transformer/src/options.rs
index 0059aaffb0ffb..c633716f6b165 100644
--- a/crates/oxc_transformer/src/options.rs
+++ b/crates/oxc_transformer/src/options.rs
@@ -7,6 +7,7 @@ pub struct TransformOptions {
 /// See <https://www.typescriptlang.org/tsconfig#target>
 #[derive(Debug, Default, Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
 pub enum TransformTarget {
+    ES5,
     ES2015,
     ES2016,
     ES2019,
diff --git a/tasks/transform_conformance/babel.snap.md b/tasks/transform_conformance/babel.snap.md
index 7a1c45439971d..1a879b2590a6f 100644
--- a/tasks/transform_conformance/babel.snap.md
+++ b/tasks/transform_conformance/babel.snap.md
@@ -1,4 +1,4 @@
-Passed: 86/1071
+Passed: 91/1078
 
 # babel-plugin-transform-class-properties
 * Failed: assumption-constantSuper/complex-super-class/input.js
@@ -750,6 +750,15 @@ Passed: 86/1071
 * Failed: regression/4403/input.js
 * Passed: exponentiation-operator/binary/input.js
 
+# babel-plugin-transform-shorthand-properties
+* Failed: shorthand-properties/method-type-annotations/input.js
+* Failed: shorthand-properties/shorthand-comments/input.js
+* Passed: shorthand-properties/method-plain/input.js
+* Passed: shorthand-properties/proto/input.js
+* Passed: shorthand-properties/shorthand-mixed/input.js
+* Passed: shorthand-properties/shorthand-multiple/input.js
+* Passed: shorthand-properties/shorthand-single/input.js
+
 # babel-plugin-transform-typescript
 * Failed: class/abstract-class-decorated/input.ts
 * Failed: class/abstract-class-decorated-method/input.ts
diff --git a/tasks/transform_conformance/src/lib.rs b/tasks/transform_conformance/src/lib.rs
index 0e02a5eb023e1..764d9a3d8b644 100644
--- a/tasks/transform_conformance/src/lib.rs
+++ b/tasks/transform_conformance/src/lib.rs
@@ -54,6 +54,8 @@ pub fn babel(options: &BabelOptions) {
         "babel-plugin-transform-async-to-generator",
         // ES2016
         "babel-plugin-transform-exponentiation-operator",
+        // ES2015
+        "babel-plugin-transform-shorthand-properties",
         // TypeScript
         "babel-plugin-transform-typescript",
         // React
@@ -133,7 +135,7 @@ fn babel_test(input_path: &Path, options: &BabelOptions) -> bool {
     let expected = output_path.and_then(|path| fs::read_to_string(path).ok());
     if let Some(expected) = &expected {
         let transform_options = TransformOptions {
-            target: TransformTarget::ES2015,
+            target: TransformTarget::ES5,
             react: Some(TransformReactOptions::default()),
         };
         let program = allocator.alloc(ret.program);
@@ -146,7 +148,7 @@ fn babel_test(input_path: &Path, options: &BabelOptions) -> bool {
         let passed = trim_transformed == trim_expected;
         if filtered {
             println!("Expected:\n");
-            println!("{expected:?}\n");
+            println!("{expected}\n");
             println!("Transformed:\n");
             println!("{transformed}\n");
             println!("Diff:\n");

From 6ed809dbdc98eb91c1ea325f9d86c3c128f85779 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Sat, 7 Oct 2023 16:35:38 +0800
Subject: [PATCH 8/9] chore: add more comments

---
 .../src/es2015/shorthand_properties.rs            | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index 392f9f2ab41b6..f5deed2a8400c 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -26,19 +26,28 @@ impl<'a> ShorthandProperties<'a> {
         obj_prop.method = false;
 
         if obj_prop.computed {
+            // all computed key can never be transformed to `__proto__` setter unexpectedly
             return;
         }
 
-        let is_proto_id = obj_prop.key.is_specific_id("__proto__");
+        // We should handle the edge case of `__proto__` property.
+        // All shorthand properties with key `__proto__` can never be `__proto__` setter.
+        // But the transformed result can be `__proto__` setter unexpectedly.
+        // It's easy to fix it by using computed property.
+
         let is_proto_string = obj_prop.key.is_specific_string_literal("__proto__");
 
-        if !is_proto_id && !is_proto_string {
+        if !is_proto_string && obj_prop.key.is_specific_id("__proto__") {
             return;
         }
+        // We reach here, it means that the key is `__proto__` or `"__proto__"`.
 
+        // Transform `__proto__`/`"__proto__"` to computed property.
         obj_prop.computed = true;
 
         if is_proto_string {
+            // After the transformation, the string literal `"__proto__"` is already expected result.
+            //
             // input:
             // "__proto__"() {}
             // output:
@@ -46,6 +55,8 @@ impl<'a> ShorthandProperties<'a> {
             return;
         }
 
+        // Convert `[__proto__]` to `["__proto__"]`
+
         let proto = StringLiteral { span: obj_prop.key.span(), value: "__proto__".into() };
         let expr = self.ast.literal_string_expression(proto);
         obj_prop.key = PropertyKey::Expression(expr);

From 83bb58232051796dde04c55008ee31e813f295c3 Mon Sep 17 00:00:00 2001
From: magic-akari <akari.ccino@gmail.com>
Date: Sat, 7 Oct 2023 16:37:45 +0800
Subject: [PATCH 9/9] fix

---
 crates/oxc_transformer/src/es2015/shorthand_properties.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/oxc_transformer/src/es2015/shorthand_properties.rs b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
index f5deed2a8400c..9442412890c55 100644
--- a/crates/oxc_transformer/src/es2015/shorthand_properties.rs
+++ b/crates/oxc_transformer/src/es2015/shorthand_properties.rs
@@ -37,7 +37,7 @@ impl<'a> ShorthandProperties<'a> {
 
         let is_proto_string = obj_prop.key.is_specific_string_literal("__proto__");
 
-        if !is_proto_string && obj_prop.key.is_specific_id("__proto__") {
+        if !is_proto_string && !obj_prop.key.is_specific_id("__proto__") {
             return;
         }
         // We reach here, it means that the key is `__proto__` or `"__proto__"`.