fix(es/minifier): typeof class should be function (#9522)

**Related issue:**

Closes #9453

Author: CPunisher

.changeset/six-hounds-hammer.md

@@ -0,0 +1,6 @@
+---
+swc_core: patch
+swc_ecma_minifier: patch
+---
+
+fix(es/minifier): typeof class should be function rather than object

crates/swc_ecma_minifier/src/compress/optimize/inline.rs

@@ -156,7 +156,7 @@ impl Optimizer<'_> {
 
             if !usage.reassigned {
                 match init {
-                    Expr::Fn(..) | Expr::Arrow(..) => {
+                    Expr::Fn(..) | Expr::Arrow(..) | Expr::Class(..) => {
                         self.typeofs.insert(ident.to_id(), "function".into());
                     }
                     Expr::Array(..) | Expr::Object(..) => {
@@ -569,12 +569,9 @@ impl Optimizer<'_> {
             if !usage.reassigned {
                 trace_op!("typeofs: Storing typeof `{}{:?}`", i.sym, i.ctxt);
                 match &*decl {
-                    Decl::Fn(..) => {
+                    Decl::Fn(..) | Decl::Class(..) => {
                         self.typeofs.insert(i.to_id(), "function".into());
                     }
-                    Decl::Class(..) => {
-                        self.typeofs.insert(i.to_id(), "object".into());
-                    }
                     _ => {}
                 }
             }

crates/swc_ecma_minifier/src/compress/optimize/ops.rs

@@ -370,7 +370,7 @@ impl Optimizer<'_> {
                     }
                 }
 
-                Expr::Arrow(..) | Expr::Fn(..) => {
+                Expr::Arrow(..) | Expr::Fn(..) | Expr::Class(..) => {
                     report_change!("Converting typeof to 'function' as we know the value");
                     self.changed = true;
                     *e = Lit::Str(Str {

crates/swc_ecma_minifier/tests/fixture/issues/9453/input.js

@@ -0,0 +1,8 @@
+"use strict";
+class x {}
+const y = x;
+const z = class {};
+console.log(typeof x);
+console.log(typeof y);
+console.log(typeof z);
+console.log(typeof class {});

crates/swc_ecma_minifier/tests/fixture/issues/9453/output.js

@@ -0,0 +1,2 @@
+"use strict";
+console.log("function"), console.log("function"), console.log("function"), console.log("function");