fix: detect bound require reexports in cjs analysis (#328)

Author: Hajime-san

src/cjs_parse.rs

@@ -184,8 +184,10 @@ impl Visit for CjsVisitor {
       self.visit_object_define(call_expr)
     } else if is_export_callee(&call_expr.callee) {
       // __export, __exportStar, tslib.__export, etc...
-      if let Some(name) = get_export_require_arg(call_expr) {
-        self.add_reexport(name);
+      if let Some(name) =
+        get_export_require_arg(call_expr, &self.var_assignments)
+      {
+        self.add_reexport(&name);
       }
     }
 
@@ -223,7 +225,10 @@ impl Visit for CjsVisitor {
       false
     }
 
-    fn get_export_require_arg(call_expr: &CallExpr) -> Option<&str> {
+    fn get_export_require_arg(
+      call_expr: &CallExpr,
+      var_assignments: &HashMap<String, String>,
+    ) -> Option<String> {
       if call_expr.args.iter().any(|a| a.spread.is_some()) {
         return None;
       }
@@ -233,10 +238,19 @@ impl Visit for CjsVisitor {
         // (0, tslib_1.__exportStar)(require("./file"), exports);
         || call_expr.args.len() == 2 && is_exports_expr(&call_expr.args[1].expr)
       {
-        get_expr_require_value(&call_expr.args[0].expr)
-      } else {
-        None
+        if let Some(require_value) =
+          get_expr_require_value(&call_expr.args[0].expr)
+        {
+          return Some(require_value.to_string());
+        }
+        if let Some(ident) = call_expr.args[0].expr.as_ident() {
+          // Handle __export(require("something"))
+          // https://github.com/nodejs/node/blob/65df9ad6438ca0c852a8f208361ae9507e072c9e/deps/merve/merve.h#L99
+          return var_assignments.get(&*ident.sym).cloned();
+        }
       }
+
+      None
     }
   }
 
@@ -250,8 +264,6 @@ impl Visit for CjsVisitor {
       AssignTarget::Simple(SimpleAssignTarget::Ident(left_ident)) => {
         if is_exports_ident(&left_ident.id) {
           self.visit_exports_right_expr(&assign_expr.right);
-        } else if let Some(right_expr) = assign_expr.right.as_assign() {
-          self.visit_assign_expr(right_expr);
         }
       }
       AssignTarget::Simple(SimpleAssignTarget::Member(left_member)) => {
@@ -263,9 +275,6 @@ impl Visit for CjsVisitor {
           // * `exports.something = other`
           if let Some(prop_name) = get_member_prop_text(&left_member.prop) {
             self.add_export(prop_name);
-            if let Some(right_expr) = assign_expr.right.as_assign() {
-              self.visit_assign_expr(right_expr);
-            }
           } else if let Some(right_member) = assign_expr.right.as_member() {
             // check for:
             // * `exports[key] = _something[key];
@@ -278,16 +287,12 @@ impl Visit for CjsVisitor {
               self.add_reexport(&require_value);
             }
           }
-        } else if let Some(right_expr) = assign_expr.right.as_assign() {
-          self.visit_assign_expr(right_expr);
-        }
-      }
-      _ => {
-        if let Some(right_expr) = assign_expr.right.as_assign() {
-          self.visit_assign_expr(right_expr);
         }
       }
+      _ => {}
     }
+
+    assign_expr.visit_children_with(self);
   }
 }
 
@@ -683,6 +688,49 @@ mod test {
     ]);
   }
 
+  #[test]
+  fn typescript_reexports_via_bound_ident() {
+    let tester = parse_cjs(
+      r#"
+    "use strict";
+      var reexported_1 = require("./reexported");
+      __export(reexported_1);
+    "#,
+    );
+
+    tester.assert_reexports(vec!["./reexported"]);
+  }
+
+  #[test]
+  fn typescript_enum_exports() {
+    let tester = parse_cjs(
+      r#"
+    "use strict";
+      var MyEnum;
+      (function (MyEnum) {
+        MyEnum[MyEnum["A"] = 0] = "A";
+        MyEnum[MyEnum["B"] = 1] = "B";
+      })(MyEnum || (MyEnum = {}));
+      exports.MyEnum = MyEnum;
+      exports.Outer = (exports.Inner = {});
+    "#,
+    );
+
+    tester.assert_exports(vec!["Inner", "MyEnum", "Outer"]);
+  }
+
+  #[test]
+  fn nested_exports_assignment_in_expression() {
+    let tester = parse_cjs(
+      r#"
+    "use strict";
+      exports.A = (exports.B = (exports.C = {}));
+    "#,
+    );
+
+    tester.assert_exports(vec!["A", "B", "C"]);
+  }
+
   #[test]
   fn rollup_babel_reexport_getter() {
     let tester = parse_cjs(