Deferred prefix support in metadata

runtime/vm/parser.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/parser.h"
 
 #include "lib/invocation_mirror.h"
 #include "platform/utils.h"
 #include "vm/bootstrap.h"
 #include "vm/class_finalizer.h"
@@ skipping 888 matching lines @@
 RawArray* Parser::EvaluateMetadata() {
   CheckToken(Token::kAT, "Metadata character '@' expected");
   GrowableObjectArray& meta_values =
       GrowableObjectArray::Handle(GrowableObjectArray::New());
   while (CurrentToken() == Token::kAT) {
     ConsumeToken();
     intptr_t expr_pos = TokenPos();
     if (!IsIdentifier()) {
       ExpectIdentifier("identifier expected");
     }
+    // Reject expressions with deferred library prefix eagerly.
+    Object& obj = Object::Handle(library_.LookupLocalObject(*CurrentLiteral()));
+    if (!obj.IsNull() && obj.IsLibraryPrefix()) {
+      if (LibraryPrefix::Cast(obj).is_deferred_load()) {
+        ErrorMsg("Metadata must be compile-time constant");
+      }
+    }
     AstNode* expr = NULL;
     if ((LookaheadToken(1) == Token::kLPAREN) ||
         ((LookaheadToken(1) == Token::kPERIOD) &&
             (LookaheadToken(3) == Token::kLPAREN)) ||
         ((LookaheadToken(1) == Token::kPERIOD) &&
             (LookaheadToken(3) == Token::kPERIOD) &&
             (LookaheadToken(5) == Token::kLPAREN))) {
       expr = ParseNewOperator(Token::kCONST);
     } else {
       // Can be x, C.x, or L.C.x.
@@ skipping 8321 matching lines @@
 AstNode* Parser::ResolveIdentInPrefixScope(intptr_t ident_pos,
                                            const LibraryPrefix& prefix,
                                            const String& ident) {
   TRACE_PARSER("ResolveIdentInPrefixScope");
   HANDLESCOPE(isolate());
   Object& obj = Object::Handle();
   if (prefix.is_loaded()) {
     obj = prefix.LookupObject(ident);
   } else {
     // Remember that this function depends on an import prefix of an
-    // unloaded deferred library.
-    parsed_function()->AddDeferredPrefix(prefix);
+    // unloaded deferred library. Note that parsed_function() can be
+    // NULL when parsing expressions outside the scope of a function.
+    if (parsed_function() != NULL) {
+      parsed_function()->AddDeferredPrefix(prefix);
+    }
   }
   if (obj.IsNull()) {
     // Unresolved prefixed primary identifier.
     return NULL;
   } else if (obj.IsClass()) {
     const Class& cls = Class::Cast(obj);
     return new PrimaryNode(ident_pos, Class::ZoneHandle(cls.raw()));
   } else if (obj.IsField()) {
     const Field& field = Field::Cast(obj);
     ASSERT(field.is_static());
@@ skipping 1608 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart