feat(minifier): minimize foo(...[]) -> foo()

Author: Boshen

crates/oxc_minifier/src/peephole/mod.rs

@@ -306,6 +306,14 @@ impl<'a> Traverse<'a> for LatePeepholeOptimizations {
     fn exit_catch_clause(&mut self, catch: &mut CatchClause<'a>, ctx: &mut TraverseCtx<'a>) {
         self.substitute_catch_clause(catch, Ctx(ctx));
     }
+
+    fn exit_call_expression(&mut self, e: &mut CallExpression<'a>, _ctx: &mut TraverseCtx<'a>) {
+        Self::remove_empty_spread_arguments(&mut e.arguments);
+    }
+
+    fn exit_new_expression(&mut self, e: &mut NewExpression<'a>, _ctx: &mut TraverseCtx<'a>) {
+        Self::remove_empty_spread_arguments(&mut e.arguments);
+    }
 }
 
 pub struct DeadCodeElimination {

crates/oxc_minifier/src/peephole/remove_dead_code.rs

@@ -620,6 +620,17 @@ impl<'a> LatePeepholeOptimizations {
     pub fn remove_dead_code_exit_class_body(body: &mut ClassBody<'a>, _ctx: Ctx<'a, '_>) {
         body.body.retain(|e| !matches!(e, ClassElement::StaticBlock(s) if s.body.is_empty()));
     }
+
+    pub fn remove_empty_spread_arguments(args: &mut Vec<'a, Argument<'a>>) {
+        if args.len() != 1 {
+            return;
+        }
+        let Argument::SpreadElement(e) = &args[0] else { return };
+        let Expression::ArrayExpression(e) = &e.argument else { return };
+        if e.elements.is_empty() {
+            args.drain(..);
+        }
+    }
 }
 
 /// <https://github.com/google/closure-compiler/blob/v20240609/test/com/google/javascript/jscomp/PeepholeRemoveDeadCodeTest.java>
@@ -898,4 +909,10 @@ mod test {
         test_same("throw foo; export let bar");
         test_same("throw foo; export default bar");
     }
+
+    #[test]
+    fn remove_empty_spread_arguments() {
+        test("foo(...[])", "foo()");
+        test("new Foo(...[])", "new Foo()");
+    }
 }