fix(es/minifier): Fix evaluation of array literals with void 0 (#8733)

**Related issue:** - Closes #8706
swc-project · Mar 12, 2024 · aa0154d · aa0154d
1 parent d9c49d8
commit aa0154d
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diff --git a/crates/swc_ecma_minifier/tests/fixture/issues/8706/config.json b/crates/swc_ecma_minifier/tests/fixture/issues/8706/config.json
@@ -0,0 +1,3 @@
+{
+    "defaults": true
+}
diff --git a/crates/swc_ecma_minifier/tests/fixture/issues/8706/input.js b/crates/swc_ecma_minifier/tests/fixture/issues/8706/input.js
@@ -0,0 +1 @@
+console.log([void 0] + 'swc');
diff --git a/crates/swc_ecma_minifier/tests/fixture/issues/8706/output.js b/crates/swc_ecma_minifier/tests/fixture/issues/8706/output.js
@@ -0,0 +1 @@
+console.log("swc");
diff --git a/crates/swc_ecma_utils/src/lib.rs b/crates/swc_ecma_utils/src/lib.rs
@@ -1027,6 +1027,16 @@ pub trait ExprExt {
                             let ExprOrSpread { ref expr, .. } = *elem;
                             match &**expr {
                                 Expr::Lit(Lit::Null(..)) => Cow::Borrowed(""),
+                                Expr::Unary(UnaryExpr {
+                                    op: op!("void"),
+                                    arg,
+                                    ..
+                                }) => {
+                                    if arg.may_have_side_effects(ctx) {
+                                        return Value::Unknown;
+                                    }
+                                    Cow::Borrowed("")
+                                }
                                 Expr::Ident(Ident { sym: undefined, .. })
                                     if &**undefined == "undefined" =>
                                 {