[modules] Detect all indirect exports and represent them as such.

src/ast/modules.h

Index: src/ast/modules.h
diff --git a/src/ast/modules.h b/src/ast/modules.h
index 4c63df9dfad2569125bb34b3fa309c0f03f0430b..a3bbb09a26832a7f94ac08d106f813fb46cc537f 100644
--- a/src/ast/modules.h
+++ b/src/ast/modules.h
@@ -62,6 +62,24 @@ class ModuleDescriptor : public ZoneObject {
     const AstRawString* module_request, const Scanner::Location loc,
     Zone* zone);
 
+  // Find any implicitly indirect exports and make them explicit.
+  //
+  // An explicitly indirect export is an export entry arising from an export
+  // statement of the following form:
+  //   export {a as c} from "X";
+  // An implicitly indirect export corresponds to
+  //   export {b as c};
+  // in the presence of an import statement of the form
+  //   import {a as b} from "X";
+  // This function finds such implicitly indirect export entries and rewrites
+  // them by filling in the import name and module request, as well as nulling
+  // out the local name.  Effectively, it turns
+  //   import {a as b} from "X"; export {b as c};
+  // into:
+  //   import {a as b} from "X"; export {a as c} from "X";
+  // (The import entry is never deleted.)
+  void MakeIndirectExportsExplicit();
+
   // Check if module is well-formed and report error if not.
   bool Validate(DeclarationScope* module_scope,
                 PendingCompilationErrorHandler* error_handler,
@@ -82,7 +100,7 @@ class ModuleDescriptor : public ZoneObject {
           module_request(nullptr) {}
   };
 
-  const ZoneList<const ModuleEntry*>& exports() const { return exports_; }
+  const ZoneList<ModuleEntry*>& exports() const { return exports_; }

[adamk, 2016/08/09 16:52:51]

Maybe remove the const-ness of this method? I realize it's still C++-const, but
it's no longer conceptually-const.

[neis, 2016/08/10 11:53:30]

I don't understand, it's just a getter.

[adamk, 2016/08/10 17:30:28]

But it now lets callers mutate the internal state of the class (the ModuleEntry
objects).

Anyway, this really doesn't matter too much, just one of those C++ things that's
easy to have different opinions on.

 
   // Empty imports and namespace imports.
   const ZoneList<const ModuleEntry*>& special_imports() const {
@@ -96,7 +114,7 @@ class ModuleDescriptor : public ZoneObject {
   }
 
  private:
-  ZoneList<const ModuleEntry*> exports_;
+  ZoneList<ModuleEntry*> exports_;
   ZoneList<const ModuleEntry*> special_imports_;
   ZoneMap<const AstRawString*, const ModuleEntry*> regular_imports_;
 };