- Properly load the core libraries as libraries and not as scripts.

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 "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
@@ skipping 4234 matching lines @@
     }
     const String& name = *CurrentLiteral();
     ConsumeToken();
     ExpectToken(Token::kRPAREN);
     ExpectToken(Token::kSEMICOLON);
     library_.SetName(name);
   }
 }
 
 
-Dart_Handle Parser::CallLibraryTagHandler(Dart_LibraryTag tag,
+RawObject* Parser::CallLibraryTagHandler(Dart_LibraryTag tag,
                                           intptr_t token_pos,
                                           const String& url) {
   Isolate* isolate = Isolate::Current();
   Dart_LibraryTagHandler handler = isolate->library_tag_handler();
   if (handler == NULL) {
+    if (url.StartsWith(Symbols::DartScheme())) {
+      if (tag == kCanonicalizeUrl) {
+        return url.raw();
+      }
+      return Object::null();
+    }
     ErrorMsg(token_pos, "no library handler registered");
   }
   Dart_Handle result = handler(tag,
                                Api::NewHandle(isolate, library_.raw()),
                                Api::NewHandle(isolate, url.raw()));
   if (Dart_IsError(result)) {
     Error& prev_error = Error::Handle();
     prev_error ^= Api::UnwrapHandle(result);
     AppendErrorMsg(prev_error, token_pos, "library handler failed");
+    UNREACHABLE();

[siva, 2013/02/23 00:11:03]

Why UNREACHABLE here (AppendErrorMsg already has one)?

[Ivan Posva, 2013/02/25 22:20:14]

I wanted to make it clear that we will not be able to continue below. Instead I
will add an appropriate comment.

   }
-  return result;
+  if (tag == kCanonicalizeUrl) {
+    if (!Dart_IsString(result)) {
+      ErrorMsg(token_pos, "library handler failed URI canonicalization");
+    }
+  }
+  return Api::UnwrapHandle(result);
 }
 
 
 // TODO(hausner): Remove support for old library definition syntax.
 void Parser::ParseLibraryImportObsoleteSyntax() {
   while (CurrentToken() == Token::kLEGACY_IMPORT) {
     const intptr_t import_pos = TokenPos();
     ConsumeToken();
     ExpectToken(Token::kLPAREN);
     if (CurrentToken() != Token::kSTRING) {
@@ skipping 14 matching lines @@
       }
       prefix = CurrentLiteral()->raw();
       // TODO(asiva): Need to also check that prefix is not a reserved keyword.
       if (!Scanner::IsIdent(prefix)) {
         ErrorMsg("prefix should be an identifier");
       }
       ConsumeToken();
     }
     ExpectToken(Token::kRPAREN);
     ExpectToken(Token::kSEMICOLON);
-    Dart_Handle handle = CallLibraryTagHandler(kCanonicalizeUrl,
-                                               import_pos,
-                                               url);
-    const String& canon_url = String::CheckedHandle(Api::UnwrapHandle(handle));
+    const String& canon_url = String::CheckedHandle(
+        CallLibraryTagHandler(kCanonicalizeUrl, import_pos, url));
     // Lookup the library URL.
     Library& library = Library::Handle(Library::LookupLibrary(canon_url));
     if (library.IsNull()) {
       // Call the library tag handler to load the library.
       CallLibraryTagHandler(kImportTag, import_pos, canon_url);
       // If the library tag handler succeded without registering the
       // library we create an empty library to import.
       library = Library::LookupLibrary(canon_url);
       if (library.IsNull()) {
         library = Library::New(canon_url);
@@ skipping 25 matching lines @@
     const intptr_t source_pos = TokenPos();
     ConsumeToken();
     ExpectToken(Token::kLPAREN);
     if (CurrentToken() != Token::kSTRING) {
       ErrorMsg("source url expected");
     }
     const String& url = *CurrentLiteral();
     ConsumeToken();
     ExpectToken(Token::kRPAREN);
     ExpectToken(Token::kSEMICOLON);
-    Dart_Handle handle = CallLibraryTagHandler(kCanonicalizeUrl,
-                                               source_pos,
-                                               url);
-    const String& canon_url = String::CheckedHandle(Api::UnwrapHandle(handle));
+    const String& canon_url = String::CheckedHandle(
+        CallLibraryTagHandler(kCanonicalizeUrl, source_pos, url));
     CallLibraryTagHandler(kSourceTag, source_pos, canon_url);
   }
 }
 
 
 void Parser::ParseLibraryName() {
   ASSERT(CurrentToken() == Token::kLIBRARY);
   ConsumeToken();
   String& lib_name = *ExpectIdentifier("library name expected");
   if (CurrentToken() == Token::kPERIOD) {
@@ skipping 66 matching lines @@
     if (show_list.Length() > 0) {
       show_names = Array::MakeArray(show_list);
     }
     if (hide_list.Length() > 0) {
       hide_names = Array::MakeArray(hide_list);
     }
   }
   ExpectSemicolon();
 
   // Canonicalize library URL.
-  Dart_Handle handle =
-      CallLibraryTagHandler(kCanonicalizeUrl, import_pos, url);
-  const String& canon_url = String::CheckedHandle(Api::UnwrapHandle(handle));
+  const String& canon_url = String::CheckedHandle(
+      CallLibraryTagHandler(kCanonicalizeUrl, import_pos, url));
   // Lookup the library URL.
   Library& library = Library::Handle(Library::LookupLibrary(canon_url));
   if (library.IsNull()) {
     // Call the library tag handler to load the library.
     CallLibraryTagHandler(kImportTag, import_pos, canon_url);
     // If the library tag handler succeded without registering the
     // library we create an empty library to import.
     library = Library::LookupLibrary(canon_url);
     if (library.IsNull()) {
       library = Library::New(canon_url);
@@ skipping 31 matching lines @@
 
 void Parser::ParseLibraryPart() {
   const intptr_t source_pos = TokenPos();
   ConsumeToken();  // Consume "part".
   if (CurrentToken() != Token::kSTRING) {
     ErrorMsg("url expected");
   }
   const String& url = *CurrentLiteral();
   ConsumeToken();
   ExpectSemicolon();
-  Dart_Handle handle =
-      CallLibraryTagHandler(kCanonicalizeUrl, source_pos, url);
-  const String& canon_url = String::CheckedHandle(Api::UnwrapHandle(handle));
+  const String& canon_url = String::CheckedHandle(
+      CallLibraryTagHandler(kCanonicalizeUrl, source_pos, url));
   CallLibraryTagHandler(kSourceTag, source_pos, canon_url);
 }
 
 
 void Parser::ParseLibraryDefinition() {
   TRACE_PARSER("ParseLibraryDefinition");
 
   // Handle the script tag.
   if (CurrentToken() == Token::kSCRIPTTAG) {
     // Nothing to do for script tags except to skip them.
@@ skipping 5530 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart