feat: Correctly handle computed object assignments

Author: kamilogorek

src/swc.rs

@@ -338,6 +338,7 @@ fn prefix_getters_setters(kind: ast::MethodKind, scope_name: &mut ScopeName) {
 /// This is only possible if the expression is an identifier or a member expression.
 fn infer_name_from_expr(mut expr: &ast::Expr) -> Option<ScopeName> {
     let mut scope_name = ScopeName::new();
+
     loop {
         match expr {
             ast::Expr::Ident(ident) => {
@@ -354,6 +355,18 @@ fn infer_name_from_expr(mut expr: &ast::Expr) -> Option<ScopeName> {
                         .push_front(NameComponent::ident(ident.clone()));
                     scope_name.components.push_front(NameComponent::interp("."));
                 }
+
+                if let Some(computed_prop) = member.prop.as_computed() {
+                    if let Some((computed_name, need_delimiter)) =
+                        computed_prop_name_to_component(computed_prop)
+                    {
+                        scope_name.components.push_front(computed_name);
+                        if need_delimiter {
+                            scope_name.components.push_front(NameComponent::interp("."));
+                        }
+                    }
+                }
+
                 expr = &member.obj;
             }
 
@@ -369,6 +382,24 @@ fn infer_name_from_expr(mut expr: &ast::Expr) -> Option<ScopeName> {
     }
 }
 
+fn computed_prop_name_to_component(prop: &ast::ComputedPropName) -> Option<(NameComponent, bool)> {
+    if let Some(lit) = prop.expr.as_lit() {
+        if let ast::Lit::Str(prop) = lit {
+            return Some((NameComponent::interp(prop.value.to_string()), true));
+        }
+
+        if let ast::Lit::Num(prop) = lit {
+            return Some((NameComponent::interp(format!("[{}]", prop.value)), false));
+        }
+    }
+
+    if let Some(ident) = prop.expr.as_ident() {
+        return Some((NameComponent::interp(format!("[{}]", ident.sym)), false));
+    }
+
+    None
+}
+
 fn prop_name_to_component(prop: &ast::PropName) -> NameComponent {
     match prop {
         ast::PropName::Ident(ref i) => NameComponent::ident(i.clone()),

tests/fixtures/trace/sync.mjs

@@ -84,3 +84,17 @@ let obj = {
     throw new Error();
   },
 };
+
+Klass.prototype[42] = function () {
+  beepBoop();
+};
+
+Klass.prototype["method"] = function () {
+  beepBoop();
+};
+
+const method = "computedMethod";
+
+Klass.prototype[method] = function () {
+  beepBoop();
+};

tests/integration.rs

@@ -69,6 +69,10 @@ fn resolves_scope_names() {
         index.lookup(offset)
     };
 
+    assert_eq!(lookup(99, 3), NamedScope("Klass.prototype[method]"));
+    assert_eq!(lookup(93, 3), NamedScope("Klass.prototype.method"));
+    assert_eq!(lookup(89, 3), NamedScope("Klass.prototype[42]"));
+
     // objectLiteralAnon@http://127.0.0.1:8080/sync.mjs:84:11
     // at Object.objectLiteralAnon (http://127.0.0.1:8080/sync.mjs:84:11)
     assert_eq!(lookup(84, 11), NamedScope("obj.objectLiteralAnon"));