fix(es/fixer): Preserve parenthesis for optional chaining (#8399)

**Related issue:**
 - Closes #8398

crates/swc/tests/fixture/issues-8xxx/8398/input/.swcrc

@@ -0,0 +1,15 @@
+{
+    "jsc": {
+        "parser": {
+            "syntax": "typescript",
+            "tsx": true
+        },
+        "target": "es2022",
+        "minify": {
+            "compress": true
+        },
+        "loose": false
+    },
+    "isModule": true,
+    "minify": true
+}

crates/swc/tests/fixture/issues-8xxx/8398/input/index.js

@@ -0,0 +1,12 @@
+(obj?.a).b;
+(obj?.a)();
+(obj?.a)[0];
+(obj?.a)`hello`;
+
+(obj.a?.()).a;
+(obj.a?.())();
+(obj.a?.())[0];
+(obj.a?.())`hello`;
+
+(((a?.b)));
+(((a?.())));

crates/swc/tests/fixture/issues-8xxx/8398/output/index.js

@@ -0,0 +1 @@
+(obj?.a).b,(obj?.a)(),(obj?.a)[0],(obj?.a)`hello`,(obj.a?.()).a,(obj.a?.())(),(obj.a?.())[0],(obj.a?.())`hello`,a?.b,a?.();

crates/swc/tests/tsc-references/checkObjectDefineProperty.1.normal.js

@@ -46,7 +46,7 @@ var needsExemplar = function() {
     var _ = arguments.length > 0 && arguments[0] !== void 0 ? arguments[0] : x;
     return void 0;
 };
-var expected = /** @type {{name: string, readonly middleInit: string, readonly lastName: string, zip: number, readonly houseNumber: number, zipStr: string}} */ /** @type {*} */ null;
+var expected = /** @type {*} */ null;
 /**
  * 
  * @param {typeof returnExemplar} a 

crates/swc/tests/tsc-references/deleteChain.1.normal.js

@@ -1,15 +1,15 @@
 //// [deleteChain.ts]
-var _o3_b, _o3_b1, _o4_b_c_d, _o4_b, _this, _o4_b1, _o4_b_c_d1, _o4_b2, _o5_b_c_d, _o5_b, _o5_b_c_d1, _o5_b1, _o6_b_c_d, _o6_b, _o6_b_c_d1, _o6_b1;
+var _o3_b, _o3_b1, _o4_b_c_d, _o4_b, _o4_b_c_d1, _o4_b1, _o4_b_c_d2, _o4_b2, _o5_b_c_d, _o5_b, _o5_b_c_d1, _o5_b1, _o6_b_c_d, _o6_b, _o6_b_c_d1, _o6_b1;
+o1 === null || o1 === void 0 ? true : delete o1.b;
 o1 === null || o1 === void 0 ? true : delete o1.b;
-delete (o1 === null || o1 === void 0 ? void 0 : o1.b);
 o2 === null || o2 === void 0 ? true : delete o2.b.c;
-delete (o2 === null || o2 === void 0 ? void 0 : o2.b.c);
+o2 === null || o2 === void 0 ? true : delete o2.b.c;
 (_o3_b = o3.b) === null || _o3_b === void 0 ? true : delete _o3_b.c;
-delete ((_o3_b1 = o3.b) === null || _o3_b1 === void 0 ? void 0 : _o3_b1.c);
+(_o3_b1 = o3.b) === null || _o3_b1 === void 0 ? true : delete _o3_b1.c;
 (_o4_b = o4.b) === null || _o4_b === void 0 ? true : (_o4_b_c_d = _o4_b.c.d) === null || _o4_b_c_d === void 0 ? true : delete _o4_b_c_d.e;
-(_this = (_o4_b1 = o4.b) === null || _o4_b1 === void 0 ? void 0 : _o4_b1.c.d) === null || _this === void 0 ? true : delete _this.e;
+(_o4_b1 = o4.b) === null || _o4_b1 === void 0 ? true : (_o4_b_c_d1 = _o4_b1.c.d) === null || _o4_b_c_d1 === void 0 ? true : delete _o4_b_c_d1.e;
-delete ((_o4_b2 = o4.b) === null || _o4_b2 === void 0 ? void 0 : (_o4_b_c_d1 = _o4_b2.c.d) === null || _o4_b_c_d1 === void 0 ? void 0 : _o4_b_c_d1.e);
+(_o4_b2 = o4.b) === null || _o4_b2 === void 0 ? true : (_o4_b_c_d2 = _o4_b2.c.d) === null || _o4_b_c_d2 === void 0 ? true : delete _o4_b_c_d2.e;
 (_o5_b = o5.b) === null || _o5_b === void 0 ? true : (_o5_b_c_d = _o5_b.call(o5).c.d) === null || _o5_b_c_d === void 0 ? true : delete _o5_b_c_d.e;
-delete ((_o5_b1 = o5.b) === null || _o5_b1 === void 0 ? void 0 : (_o5_b_c_d1 = _o5_b1.call(o5).c.d) === null || _o5_b_c_d1 === void 0 ? void 0 : _o5_b_c_d1.e);
+(_o5_b1 = o5.b) === null || _o5_b1 === void 0 ? true : (_o5_b_c_d1 = _o5_b1.call(o5).c.d) === null || _o5_b_c_d1 === void 0 ? true : delete _o5_b_c_d1.e;
 (_o6_b = o6.b) === null || _o6_b === void 0 ? true : (_o6_b_c_d = _o6_b["c"].d) === null || _o6_b_c_d === void 0 ? true : delete _o6_b_c_d["e"];
-delete ((_o6_b1 = o6.b) === null || _o6_b1 === void 0 ? void 0 : (_o6_b_c_d1 = _o6_b1["c"].d) === null || _o6_b_c_d1 === void 0 ? void 0 : _o6_b_c_d1["e"]);
+(_o6_b1 = o6.b) === null || _o6_b1 === void 0 ? true : (_o6_b_c_d1 = _o6_b1["c"].d) === null || _o6_b_c_d1 === void 0 ? true : delete _o6_b_c_d1["e"];

crates/swc/tests/tsc-references/deleteChain.2.minified.js

@@ -1,3 +1,3 @@
 //// [deleteChain.ts]
-var _o3_b, _o3_b1, _o4_b_c_d, _o4_b, _this, _o4_b1, _o4_b_c_d1, _o4_b2, _o5_b_c_d, _o5_b, _o5_b_c_d1, _o5_b1, _o6_b_c_d, _o6_b, _o6_b_c_d1, _o6_b1;
+var _o3_b, _o3_b1, _o4_b_c_d, _o4_b, _o4_b_c_d1, _o4_b1, _o4_b_c_d2, _o4_b2, _o5_b_c_d, _o5_b, _o5_b_c_d1, _o5_b1, _o6_b_c_d, _o6_b, _o6_b_c_d1, _o6_b1;
-null == o1 || delete o1.b, delete (null == o1 ? void 0 : o1.b), null == o2 || delete o2.b.c, delete (null == o2 ? void 0 : o2.b.c), null === (_o3_b = o3.b) || void 0 === _o3_b || delete _o3_b.c, delete (null === (_o3_b1 = o3.b) || void 0 === _o3_b1 ? void 0 : _o3_b1.c), null === (_o4_b = o4.b) || void 0 === _o4_b || null === (_o4_b_c_d = _o4_b.c.d) || void 0 === _o4_b_c_d || delete _o4_b_c_d.e, null === (_this = null === (_o4_b1 = o4.b) || void 0 === _o4_b1 ? void 0 : _o4_b1.c.d) || void 0 === _this || delete _this.e, delete (null === (_o4_b2 = o4.b) || void 0 === _o4_b2 ? void 0 : null === (_o4_b_c_d1 = _o4_b2.c.d) || void 0 === _o4_b_c_d1 ? void 0 : _o4_b_c_d1.e), null === (_o5_b = o5.b) || void 0 === _o5_b || null === (_o5_b_c_d = _o5_b.call(o5).c.d) || void 0 === _o5_b_c_d || delete _o5_b_c_d.e, delete (null === (_o5_b1 = o5.b) || void 0 === _o5_b1 ? void 0 : null === (_o5_b_c_d1 = _o5_b1.call(o5).c.d) || void 0 === _o5_b_c_d1 ? void 0 : _o5_b_c_d1.e), null === (_o6_b = o6.b) || void 0 === _o6_b || null === (_o6_b_c_d = _o6_b.c.d) || void 0 === _o6_b_c_d || delete _o6_b_c_d.e, delete (null === (_o6_b1 = o6.b) || void 0 === _o6_b1 ? void 0 : null === (_o6_b_c_d1 = _o6_b1.c.d) || void 0 === _o6_b_c_d1 ? void 0 : _o6_b_c_d1.e);
+null == o1 || delete o1.b, null == o1 || delete o1.b, null == o2 || delete o2.b.c, null == o2 || delete o2.b.c, null === (_o3_b = o3.b) || void 0 === _o3_b || delete _o3_b.c, null === (_o3_b1 = o3.b) || void 0 === _o3_b1 || delete _o3_b1.c, null === (_o4_b = o4.b) || void 0 === _o4_b || null === (_o4_b_c_d = _o4_b.c.d) || void 0 === _o4_b_c_d || delete _o4_b_c_d.e, null === (_o4_b1 = o4.b) || void 0 === _o4_b1 || null === (_o4_b_c_d1 = _o4_b1.c.d) || void 0 === _o4_b_c_d1 || delete _o4_b_c_d1.e, null === (_o4_b2 = o4.b) || void 0 === _o4_b2 || null === (_o4_b_c_d2 = _o4_b2.c.d) || void 0 === _o4_b_c_d2 || delete _o4_b_c_d2.e, null === (_o5_b = o5.b) || void 0 === _o5_b || null === (_o5_b_c_d = _o5_b.call(o5).c.d) || void 0 === _o5_b_c_d || delete _o5_b_c_d.e, null === (_o5_b1 = o5.b) || void 0 === _o5_b1 || null === (_o5_b_c_d1 = _o5_b1.call(o5).c.d) || void 0 === _o5_b_c_d1 || delete _o5_b_c_d1.e, null === (_o6_b = o6.b) || void 0 === _o6_b || null === (_o6_b_c_d = _o6_b.c.d) || void 0 === _o6_b_c_d || delete _o6_b_c_d.e, null === (_o6_b1 = o6.b) || void 0 === _o6_b1 || null === (_o6_b_c_d1 = _o6_b1.c.d) || void 0 === _o6_b_c_d1 || delete _o6_b_c_d1.e;

crates/swc/tests/tsc-references/importTypeInJSDoc.1.normal.js

@@ -11,7 +11,7 @@
 //// [index.js]
 /**
  * @typedef {import("./externs")} Foo
- */ let a = /** @type {Foo} */ /** @type {*} */ undefined;
+ */ let a = /** @type {*} */ undefined;
 a = new Foo({
     doer: Foo.Bar
 });

crates/swc/tests/tsc-references/optionalChainingInTypeAssertions(target=es2015).1.normal.js

@@ -8,8 +8,8 @@ const foo = new Foo();
 (_foo_m1 = foo.m) === null || _foo_m1 === void 0 ? void 0 : _foo_m1.call(foo);
 (_foo_m2 = foo.m) === null || _foo_m2 === void 0 ? void 0 : _foo_m2.call(foo);
 (_foo_m3 = foo.m) === null || _foo_m3 === void 0 ? void 0 : _foo_m3.call(foo);
-// https://github.com/microsoft/TypeScript/issues/50148
+(// https://github.com/microsoft/TypeScript/issues/50148
-(foo === null || foo === void 0 ? void 0 : foo.m).length;
+foo === null || foo === void 0 ? void 0 : foo.m).length;
 (foo === null || foo === void 0 ? void 0 : foo.m).length;
 (foo === null || foo === void 0 ? void 0 : foo["m"]).length;
 (foo === null || foo === void 0 ? void 0 : foo["m"]).length;

crates/swc/tests/tsc-references/optionalChainingInTypeAssertions(target=es2022).2.minified.js

@@ -2,4 +2,4 @@
 const foo = new class {
     m() {}
 }();
-foo.m?.(), foo.m?.(), foo.m?.(), foo.m?.(), foo?.m.length, foo?.m.length, foo?.m.length, foo?.m.length;
+foo.m?.(), foo.m?.(), foo.m?.(), foo.m?.(), (foo?.m).length, (foo?.m).length, (foo?.m).length, (foo?.m).length;

crates/swc_ecma_minifier/src/compress/pure/mod.rs

@@ -334,10 +334,6 @@ impl VisitMut for Pure<'_> {
     }
 
     fn visit_mut_expr(&mut self, e: &mut Expr) {
-        if let Expr::Paren(p) = e {
-            *e = *p.expr.take();
-        }
-
         {
             let ctx = Ctx {
                 in_first_expr: false,

crates/swc_ecma_minifier/src/metadata/mod.rs

@@ -97,7 +97,13 @@ impl VisitMut for InfoMarker<'_> {
     fn visit_mut_call_expr(&mut self, n: &mut CallExpr) {
         n.visit_mut_children_with(self);
 
-        if has_noinline(self.comments, n.span) {
+        // TODO: remove after we figure out how to move comments properly
+        if has_noinline(self.comments, n.span)
+            || match &n.callee {
+                Callee::Expr(e) => has_noinline(self.comments, e.span()),
+                _ => false,
+            }
+        {
             n.span = n.span.apply_mark(self.marks.noinline);
         }
 

crates/swc_ecma_minifier/src/pass/precompress.rs

@@ -8,6 +8,7 @@ use crate::HEAVY_TASK_PARALLELS;
 /// Optimizer invoked before invoking compressor.
 ///
 /// - Remove parens.
+/// TODO: remove completely after #8333
 pub(crate) fn precompress_optimizer<'a>() -> impl 'a + VisitMut {
     PrecompressOptimizer {}
 }
@@ -26,14 +27,6 @@ impl Parallel for PrecompressOptimizer {
 impl VisitMut for PrecompressOptimizer {
     noop_visit_mut_type!();
 
-    fn visit_mut_expr(&mut self, e: &mut Expr) {
-        e.visit_mut_children_with(self);
-
-        if let Expr::Paren(p) = e {
-            *e = *p.expr.take();
-        }
-    }
-
     fn visit_mut_pat_or_expr(&mut self, n: &mut PatOrExpr) {
         n.visit_mut_children_with(self);
 

crates/swc_ecma_minifier/tests/compress.rs

@@ -39,7 +39,11 @@ use swc_ecma_parser::{
     EsConfig, Parser, Syntax,
 };
 use swc_ecma_testing::{exec_node_js, JsExecOptions};
-use swc_ecma_transforms_base::{fixer::fixer, hygiene::hygiene, resolver};
+use swc_ecma_transforms_base::{
+    fixer::{fixer, paren_remover},
+    hygiene::hygiene,
+    resolver,
+};
 use swc_ecma_utils::drop_span;
 use swc_ecma_visit::{FoldWith, Visit, VisitMut, VisitMutWith, VisitWith};
 use testing::{assert_eq, unignore_fixture, DebugUsingDisplay, NormalizedOutput};
@@ -194,7 +198,12 @@ fn run(
             .map_err(|err| {
                 err.into_diagnostic(handler).emit();
             })
-            .map(|module| module.fold_with(&mut resolver(unresolved_mark, top_level_mark, false)));
+            .map(|mut module| {
+                module.visit_mut_with(&mut paren_remover(Some(&comments)));
+                module.visit_mut_with(&mut resolver(unresolved_mark, top_level_mark, false));
+
+                module
+            });
 
         // Ignore parser errors.
         //

crates/swc_ecma_minifier/tests/fixture/issues/8398/input.js

@@ -0,0 +1 @@
+(obj?.a).b;

crates/swc_ecma_minifier/tests/fixture/issues/8398/output.js

@@ -0,0 +1 @@
+(obj?.a).b;

crates/swc_ecma_minifier/tests/terser_exec.rs

@@ -32,7 +32,11 @@ use swc_ecma_parser::{
     lexer::{input::SourceFileInput, Lexer},
     EsConfig, Parser, Syntax,
 };
-use swc_ecma_transforms_base::{fixer::fixer, hygiene::hygiene, resolver};
+use swc_ecma_transforms_base::{
+    fixer::{fixer, paren_remover},
+    hygiene::hygiene,
+    resolver,
+};
 use swc_ecma_visit::{FoldWith, VisitMutWith};
 use testing::assert_eq;
 
@@ -197,7 +201,12 @@ fn run(cm: Lrc<SourceMap>, handler: &Handler, input: &Path, config: &str) -> Opt
             .map_err(|err| {
                 err.into_diagnostic(handler).emit();
             })
-            .map(|module| module.fold_with(&mut resolver(unresolved_mark, top_level_mark, false)));
+            .map(|mut module| {
+                module.visit_mut_with(&mut paren_remover(Some(&comments)));
+                module.visit_mut_with(&mut resolver(unresolved_mark, top_level_mark, false));
+
+                module
+            });
 
         // Ignore parser errors.
         //

crates/swc_ecma_transforms_base/src/fixer.rs

@@ -1,4 +1,4 @@
-use std::{hash::BuildHasherDefault, ops::RangeFull};
+use std::{hash::BuildHasherDefault, mem, ops::RangeFull};
 
 use indexmap::IndexMap;
 use rustc_hash::FxHasher;
@@ -18,6 +18,7 @@ pub fn fixer(comments: Option<&dyn Comments>) -> impl '_ + Fold + VisitMut {
         ctx: Default::default(),
         span_map: Default::default(),
         in_for_stmt_head: Default::default(),
+        in_opt_chain: Default::default(),
         remove_only: false,
     })
 }
@@ -28,6 +29,7 @@ pub fn paren_remover(comments: Option<&dyn Comments>) -> impl '_ + Fold + VisitM
         ctx: Default::default(),
         span_map: Default::default(),
         in_for_stmt_head: Default::default(),
+        in_opt_chain: Default::default(),
         remove_only: true,
     })
 }
@@ -42,6 +44,7 @@ struct Fixer<'a> {
     span_map: IndexMap<Span, Span, BuildHasherDefault<FxHasher>>,
 
     in_for_stmt_head: bool,
+    in_opt_chain: bool,
 
     remove_only: bool,
 }
@@ -84,21 +87,6 @@ macro_rules! array {
 }
 
 impl Fixer<'_> {
-    fn visit_call<T: VisitMutWith<Self>>(
-        &mut self,
-        args: &mut Vec<ExprOrSpread>,
-        callee: &mut T,
-    ) -> Context {
-        let old = self.ctx;
-        self.ctx = Context::ForcedExpr;
-        args.visit_mut_with(self);
-
-        self.ctx = Context::Callee { is_new: false };
-        callee.visit_mut_with(self);
-
-        old
-    }
-
     fn wrap_callee(&mut self, e: &mut Expr) {
         match e {
             Expr::Lit(Lit::Num(..) | Lit::Str(..)) => (),
@@ -397,24 +385,47 @@ impl VisitMut for Fixer<'_> {
     }
 
     fn visit_mut_call_expr(&mut self, node: &mut CallExpr) {
-        let old = self.visit_call(&mut node.args, &mut node.callee);
+        let ctx = mem::replace(&mut self.ctx, Context::Callee { is_new: false });
+
+        node.callee.visit_mut_with(self);
         if let Callee::Expr(e) = &mut node.callee {
-            if let Expr::OptChain(_) = &**e {
+            match &**e {
-                self.wrap(e)
+                Expr::OptChain(_) if !self.in_opt_chain => self.wrap(e),
-            } else {
+                _ => self.wrap_callee(e),
-                self.wrap_callee(e)
             }
         }
 
-        self.ctx = old;
+        self.ctx = Context::ForcedExpr;
+
+        node.args.visit_mut_with(self);
+
+        self.ctx = ctx;
+    }
+
+    fn visit_mut_opt_chain_base(&mut self, n: &mut OptChainBase) {
+        if !n.is_member() {
+            n.visit_mut_children_with(self);
+            return;
+        }
+
+        let in_opt_chain = mem::replace(&mut self.in_opt_chain, true);
+        n.visit_mut_children_with(self);
+        self.in_opt_chain = in_opt_chain;
     }
 
     fn visit_mut_opt_call(&mut self, node: &mut OptCall) {
-        let old = self.visit_call(&mut node.args, &mut node.callee);
+        let ctx = mem::replace(&mut self.ctx, Context::Callee { is_new: false });
+        let in_opt_chain = mem::replace(&mut self.in_opt_chain, true);
 
+        node.callee.visit_mut_with(self);
         self.wrap_callee(&mut node.callee);
 
-        self.ctx = old;
+        self.in_opt_chain = in_opt_chain;
+
+        self.ctx = Context::ForcedExpr;
+        node.args.visit_mut_with(self);
+
+        self.ctx = ctx;
     }
 
     fn visit_mut_class(&mut self, node: &mut Class) {
@@ -471,6 +482,7 @@ impl VisitMut for Fixer<'_> {
             }
         }
         self.unwrap_expr(e);
+
         e.visit_mut_children_with(self);
 
         self.ctx = ctx;
@@ -575,32 +587,31 @@ impl VisitMut for Fixer<'_> {
     }
 
     fn visit_mut_member_expr(&mut self, n: &mut MemberExpr) {
-        n.obj.visit_mut_with(self);
+        n.visit_mut_children_with(self);
-        n.prop.visit_mut_with(self);
 
-        match n {
+        match *n.obj {
-            MemberExpr { obj, .. }
+            Expr::Object(..) if self.ctx == Context::ForcedExpr => {}
-                if obj.is_object() && matches!(self.ctx, Context::ForcedExpr) => {}
+            Expr::Fn(..)
-
+            | Expr::Cond(..)
-            MemberExpr { obj, .. }
+            | Expr::Unary(..)
-                if obj.is_fn_expr()
+            | Expr::Seq(..)
-                    || obj.is_cond()
+            | Expr::Update(..)
-                    || obj.is_unary()
+            | Expr::Bin(..)
-                    || obj.is_seq()
+            | Expr::Object(..)
-                    || obj.is_update()
+            | Expr::Assign(..)
-                    || obj.is_bin()
+            | Expr::Arrow(..)
-                    || obj.is_object()
+            | Expr::Class(..)
-                    || obj.is_assign()
+            | Expr::Yield(..)
-                    || obj.is_arrow()
+            | Expr::Await(..)
-                    || obj.is_class()
+            | Expr::New(NewExpr { args: None, .. }) => {
-                    || obj.is_yield_expr()
+                self.wrap(&mut n.obj);
-                    || obj.is_await_expr()
+            }
-                    || (obj.is_call() && matches!(self.ctx, Context::Callee { is_new: true }))
+            Expr::Call(..) if self.ctx == Context::Callee { is_new: true } => {
-                    || matches!(**obj, Expr::New(NewExpr { args: None, .. })) =>
+                self.wrap(&mut n.obj);
-            {
+            }
-                self.wrap(obj);
+            Expr::OptChain(..) if !self.in_opt_chain => {
+                self.wrap(&mut n.obj);
             }
-
             _ => {}
         }
     }
@@ -691,7 +702,8 @@ impl VisitMut for Fixer<'_> {
         e.visit_mut_children_with(self);
 
         match &*e.tag {
-            Expr::Arrow(..)
+            Expr::OptChain(..)
+            | Expr::Arrow(..)
             | Expr::Cond(..)
             | Expr::Bin(..)
             | Expr::Seq(..)
@@ -857,17 +869,13 @@ impl Fixer<'_> {
                     }
                 }
 
-                let expr = Expr::Seq(SeqExpr { span: *span, exprs });
+                let mut expr = Expr::Seq(SeqExpr { span: *span, exprs });
 
-                match self.ctx {
+                if let Context::ForcedExpr = self.ctx {
-                    Context::ForcedExpr => {
+                    self.wrap(&mut expr);
-                        *e = Expr::Paren(ParenExpr {
-                            span: *span,
-                            expr: Box::new(expr),
-                        })
-                    }
-                    _ => *e = expr,
                 };
+
+                *e = expr;
             }
 
             Expr::Cond(expr) => {
@@ -907,10 +915,7 @@ impl Fixer<'_> {
                 || callee.is_await_expr()
                 || callee.is_assign() =>
             {
-                *callee = Box::new(Expr::Paren(ParenExpr {
+                self.wrap(callee);
-                    span: callee.span(),
-                    expr: callee.take(),
-                }))
             }
             Expr::OptChain(OptChainExpr { base, .. }) => match &mut **base {
                 OptChainBase::Call(OptCall { callee, .. })
@@ -919,10 +924,7 @@ impl Fixer<'_> {
                         || callee.is_await_expr()
                         || callee.is_assign() =>
                 {
-                    *callee = Box::new(Expr::Paren(ParenExpr {
+                    self.wrap(callee);
-                        span: callee.span(),
-                        expr: callee.take(),
-                    }))
                 }
 
                 OptChainBase::Call(OptCall { callee, .. }) if callee.is_fn_expr() => match self.ctx
@@ -974,51 +976,31 @@ impl Fixer<'_> {
         };
 
         let expr = Box::new(e.take());
-        *e = Expr::Paren(ParenExpr { expr, span })
+        *e = Expr::Paren(ParenExpr { expr, span });
     }
 
     /// Removes paren
     fn unwrap_expr(&mut self, e: &mut Expr) {
-        match e {
+        loop {
-            Expr::Seq(SeqExpr { exprs, .. }) if exprs.len() == 1 => {
+            match e {
-                self.unwrap_expr(exprs.last_mut().unwrap());
+                Expr::Seq(SeqExpr { exprs, .. }) if exprs.len() == 1 => {
-                *e = *exprs.last_mut().unwrap().take();
+                    *e = *exprs[0].take();
-            }
-
-            Expr::Paren(ParenExpr {
-                span: paren_span,
-                expr,
-                ..
-            }) => {
-                // `(a?.b).c !== a?.b.c`
-                if expr.is_opt_chain() {
-                    return;
                 }
 
-                // `(a?.b.c)() !== a?.b.c()`
+                Expr::Paren(ParenExpr {
-                if Self::contain_opt_chain(expr) {
+                    span: paren_span,
-                    return;
+                    expr,
+                    ..
+                }) => {
+                    let expr_span = expr.span();
+                    let paren_span = *paren_span;
+                    *e = *expr.take();
+
+                    self.span_map.insert(expr_span, paren_span);
                 }
 
-                let expr_span = expr.span();
+                _ => return,
-                let paren_span = *paren_span;
-                self.unwrap_expr(expr);
-                *e = *expr.take();
-
-                self.span_map.insert(expr_span, paren_span);
             }
-            _ => {}
-        }
-    }
-
-    fn contain_opt_chain(e: &Expr) -> bool {
-        match e {
-            Expr::Member(member) => Self::contain_opt_chain(&member.obj),
-            Expr::OptChain(_) => true,
-            Expr::Call(CallExpr { callee, .. }) if callee.is_expr() => {
-                Self::contain_opt_chain(callee.as_expr().unwrap())
-            }
-            _ => false,
         }
     }
 

crates/swc_ecma_transforms_optimization/src/simplify/branch/tests.rs

@@ -1,5 +1,5 @@
 use swc_common::{chain, Mark, SyntaxContext};
-use swc_ecma_transforms_base::resolver;
+use swc_ecma_transforms_base::{fixer::paren_remover, resolver};
 use swc_ecma_utils::ExprCtx;
 use swc_ecma_visit::as_folder;
 
@@ -15,6 +15,7 @@ macro_rules! test_stmt {
 
                 chain!(
                     resolver(unresolved_mark, top_level_mark, false),
+                    paren_remover(None),
                     expr_simplifier(top_level_mark, Default::default()),
                     as_folder(super::Remover {
                         changed: false,

crates/swc_ecma_transforms_optimization/src/simplify/expr/mod.rs

@@ -1278,15 +1278,8 @@ impl VisitMut for SimplifyExpr {
 
         match expr {
             // Do nothing.
-            Expr::Lit(_) | Expr::This(..) => return,
+            // Note: Paren should be handled in fixer
-
+            Expr::Lit(_) | Expr::This(..) | Expr::Paren(..) => return,
-            // Remove parenthesis. This may break ast, but it will be fixed up later.
-            Expr::Paren(ParenExpr { expr: e, .. }) => {
-                self.changed = true;
-
-                *expr = *e.take();
-                return;
-            }
 
             Expr::Seq(seq) if seq.exprs.is_empty() => return,
 

crates/swc_ecma_transforms_optimization/src/simplify/expr/tests.rs

@@ -1,5 +1,5 @@
 use swc_common::{chain, Mark, SyntaxContext};
-use swc_ecma_transforms_base::resolver;
+use swc_ecma_transforms_base::{fixer::paren_remover, resolver};
 use swc_ecma_transforms_testing::test_transform;
 use swc_ecma_utils::ExprCtx;
 use swc_ecma_visit::as_folder;
@@ -15,6 +15,7 @@ fn fold(src: &str, expected: &str) {
 
             chain!(
                 resolver(unresolved_mark, top_level_mark, false),
+                paren_remover(None),
                 as_folder(SimplifyExpr {
                     expr_ctx: ExprCtx {
                         unresolved_ctxt: SyntaxContext::empty().apply_mark(unresolved_mark),

crates/swc_html_minifier/src/lib.rs

@@ -2032,6 +2032,11 @@ impl Minifier<'_> {
             &mut swc_ecma_transforms_base::resolver(unresolved_mark, top_level_mark, false),
         );
 
+        let program = swc_ecma_visit::FoldWith::fold_with(
+            program,
+            &mut swc_ecma_transforms_base::fixer::paren_remover(Some(&comments)),
+        );
+
         let program = swc_ecma_minifier::optimize(
             program,
             cm.clone(),