From 02bfbfeef56b45825b86ce1808695a75268f0067 Mon Sep 17 00:00:00 2001
From: Dunqing <29533304+Dunqing@users.noreply.github.com>
Date: Sun, 13 Oct 2024 08:03:37 +0000
Subject: [PATCH] fix(codegen): preserve parenthesis for `ChainExpression`
 (#6430)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

close: #6385

The fixing way was referenced from `esbuild`, it is according to these [states](https://github.com/evanw/esbuild/blob/332727499e62315cff4ecaff9fa8b86336555e46/internal/js_ast/js_ast.go#L590-L604
)(determined in the parser) to determine whether to print parenthesis

Due to differences in implementation details, we are unable to record certain information like `esbuild` does in its parser. But fortunately, The `ParenthesisExpression` AST is actually like what `esbuild` stored states.
---
 crates/oxc_ast/src/precedence.rs              | 13 +++++--
 crates/oxc_codegen/src/gen.rs                 |  4 +--
 .../oxc_codegen/tests/integration/esbuild.rs  | 34 ++++++++++++++++++-
 3 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/crates/oxc_ast/src/precedence.rs b/crates/oxc_ast/src/precedence.rs
index 56e54b46ed199..12d84eeb0f7b9 100644
--- a/crates/oxc_ast/src/precedence.rs
+++ b/crates/oxc_ast/src/precedence.rs
@@ -2,9 +2,10 @@ use oxc_syntax::precedence::{GetPrecedence, Precedence};
 
 use crate::ast::{
     match_member_expression, AssignmentExpression, AwaitExpression, BinaryExpression,
-    CallExpression, ComputedMemberExpression, ConditionalExpression, Expression, ImportExpression,
-    LogicalExpression, MemberExpression, NewExpression, PrivateFieldExpression, SequenceExpression,
-    StaticMemberExpression, TSTypeAssertion, UnaryExpression, UpdateExpression, YieldExpression,
+    CallExpression, ChainExpression, ComputedMemberExpression, ConditionalExpression, Expression,
+    ImportExpression, LogicalExpression, MemberExpression, NewExpression, PrivateFieldExpression,
+    SequenceExpression, StaticMemberExpression, TSTypeAssertion, UnaryExpression, UpdateExpression,
+    YieldExpression,
 };
 
 impl<'a> GetPrecedence for Expression<'a> {
@@ -103,6 +104,12 @@ impl<'a> GetPrecedence for NewExpression<'a> {
     }
 }
 
+impl<'a> GetPrecedence for ChainExpression<'a> {
+    fn precedence(&self) -> Precedence {
+        Precedence::Member
+    }
+}
+
 impl<'a> GetPrecedence for MemberExpression<'a> {
     fn precedence(&self) -> Precedence {
         Precedence::Member
diff --git a/crates/oxc_codegen/src/gen.rs b/crates/oxc_codegen/src/gen.rs
index 089bed38e3f1b..299b94885c0b9 100644
--- a/crates/oxc_codegen/src/gen.rs
+++ b/crates/oxc_codegen/src/gen.rs
@@ -2047,12 +2047,12 @@ impl<'a> GenExpr for AwaitExpression<'a> {
 
 impl<'a> GenExpr for ChainExpression<'a> {
     fn gen_expr(&self, p: &mut Codegen, precedence: Precedence, ctx: Context) {
-        match &self.expression {
+        p.wrap(precedence >= Precedence::Postfix, |p| match &self.expression {
             ChainElement::CallExpression(expr) => expr.print_expr(p, precedence, ctx),
             match_member_expression!(ChainElement) => {
                 self.expression.to_member_expression().print_expr(p, precedence, ctx);
             }
-        }
+        });
     }
 }
 
diff --git a/crates/oxc_codegen/tests/integration/esbuild.rs b/crates/oxc_codegen/tests/integration/esbuild.rs
index ed655a3e39778..c03e431baad49 100644
--- a/crates/oxc_codegen/tests/integration/esbuild.rs
+++ b/crates/oxc_codegen/tests/integration/esbuild.rs
@@ -1,4 +1,6 @@
-//! Tests ported from [esbuild](https://github.com/evanw/esbuild/blob/main/internal/js_printer/js_printer_test.go#L164)
+//! Tests ported from `esbuild`
+//! * <https://github.com/evanw/esbuild/blob/main/internal/js_printer/js_printer_test.go>
+//! * <https://github.com/evanw/esbuild/blob/main/internal/js_parser/js_parser_test.go>
 
 use crate::tester::{test, test_minify};
 
@@ -1155,3 +1157,33 @@ fn test_using() {
     test_minify("await using x = y", "await using x=y;");
     test_minify("await using x = y, z = _", "await using x=y,z=_;");
 }
+
+#[test]
+fn test_preserve_optional_chain_parentheses() {
+    test("a?.b.c", "a?.b.c;\n");
+    test("(a?.b).c", "(a?.b).c;\n");
+    test("a?.b.c.d", "a?.b.c.d;\n");
+    test("(a?.b.c).d", "(a?.b.c).d;\n");
+    test("a?.b[c]", "a?.b[c];\n");
+    test("(a?.b)[c]", "(a?.b)[c];\n");
+    test("a?.b(c)", "a?.b(c);\n");
+    test("(a?.b)(c)", "(a?.b)(c);\n");
+
+    test("a?.[b][c]", "a?.[b][c];\n");
+    test("(a?.[b])[c]", "(a?.[b])[c];\n");
+    test("a?.[b][c][d]", "a?.[b][c][d];\n");
+    test("(a?.[b][c])[d]", "(a?.[b][c])[d];\n");
+    test("a?.[b].c", "a?.[b].c;\n");
+    test("(a?.[b]).c", "(a?.[b]).c;\n");
+    test("a?.[b](c)", "a?.[b](c);\n");
+    test("(a?.[b])(c)", "(a?.[b])(c);\n");
+
+    test("a?.(b)(c)", "a?.(b)(c);\n");
+    test("(a?.(b))(c)", "(a?.(b))(c);\n");
+    test("a?.(b)(c)(d)", "a?.(b)(c)(d);\n");
+    test("(a?.(b)(c))(d)", "(a?.(b)(c))(d);\n");
+    test("a?.(b).c", "a?.(b).c;\n");
+    test("(a?.(b)).c", "(a?.(b)).c;\n");
+    test("a?.(b)[c]", "a?.(b)[c];\n");
+    test("(a?.(b))[c]", "(a?.(b))[c];\n");
+}