Refactor URI processing of native extensions directive #import("dart-ext:foo").

runtime/bin/main.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 <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 #include "include/dart_debugger_api.h"
@@ skipping 245 matching lines @@
     }
     // Resolve the url within the context of the library's URL.
     Dart_Handle builtin_lib = Builtin::LoadLibrary(Builtin::kBuiltinLibrary);
     Dart_Handle library_url = Dart_LibraryUrl(library);
     if (Dart_IsError(library_url)) {
       return library_url;
     }
     Dart_Handle dart_args[2];
     dart_args[0] = library_url;
     dart_args[1] = url;
-    if (is_dart_extension_url) {
-      return Dart_Invoke(
-          builtin_lib, Dart_NewString("_resolveExtensionUri"), 2, dart_args);
-    } else {
-      return Dart_Invoke(
-          builtin_lib, Dart_NewString("_resolveUri"), 2, dart_args);
-    }
+    return Dart_Invoke(
+        builtin_lib, Dart_NewString("_resolveUri"), 2, dart_args);
   }
   if (is_dart_scheme_url) {
     ASSERT(tag == kImportTag);
     // Handle imports of other built-in libraries present in the SDK.
     if (DartUtils::IsDartIOLibURL(url_string)) {
       return Builtin::LoadLibrary(Builtin::kIOLibrary);
     } else if (DartUtils::IsDartJsonLibURL(url_string)) {
       return Builtin::LoadLibrary(Builtin::kJsonLibrary);
     } else if (DartUtils::IsDartUriLibURL(url_string)) {
       return Builtin::LoadLibrary(Builtin::kUriLibrary);
     } else if (DartUtils::IsDartUtfLibURL(url_string)) {
       return Builtin::LoadLibrary(Builtin::kUtfLibrary);
     } else {
       return Dart_Error("Do not know how to load '%s'", url_string);
     }
-  } else if (is_dart_extension_url) {
-    if (tag != kImportTag) {
-      return Dart_Error("Dart extensions must use import: '%s'", url_string);
-    }
-    return Extensions::LoadExtension(url_string, library);
   } else {
     // Get the file path out of the url.
     Dart_Handle builtin_lib = Builtin::LoadLibrary(Builtin::kBuiltinLibrary);
     Dart_Handle dart_args[1];
     dart_args[0] = url;
     Dart_Handle file_path = Dart_Invoke(
         builtin_lib, Dart_NewString("_filePathFromUri"), 1, dart_args);
     if (Dart_IsError(file_path)) {
       return file_path;
     }
     Dart_StringToCString(file_path, &url_string);
   }
+  if (is_dart_extension_url) {
+    if (tag != kImportTag) {
+      return Dart_Error("Dart extensions must use import: '%s'", url_string);
+    }
+    return Extensions::LoadExtension(url_string, library);
+  }
   result = DartUtils::LoadSource(NULL,
                                  library,
                                  url,
                                  tag,
                                  url_string,
                                  import_map);
   if (!Dart_IsError(result) && (tag == kImportTag)) {
     Builtin::ImportLibrary(result, Builtin::kBuiltinLibrary);
   }
   return result;
@@ skipping 291 matching lines @@
   Dart_ShutdownIsolate();
   // Terminate process exit-code handler.
   Process::TerminateExitCodeHandler();
 
   free(const_cast<char*>(original_script_name));
   free(const_cast<char*>(original_working_directory));
   free(const_cast<char*>(original_script_url));
 
   return 0;
 }