Error reporting on File in dart:io

runtime/bin/file_impl.dart

Index: runtime/bin/file_impl.dart
diff --git a/runtime/bin/file_impl.dart b/runtime/bin/file_impl.dart
index 8ab5bbbf29afdd5e61c5212dd2c4bdf2f46cc393..2fcf36e4829a5f91a95a291a135f030e951ad7ad 100644
--- a/runtime/bin/file_impl.dart
+++ b/runtime/bin/file_impl.dart
@@ -251,7 +251,7 @@ class _FileUtils {
   }
 
   static bool exists(String name) native "File_Exists";
-  static int open(String name, int mode) native "File_Open";
+  static open(String name, int mode) native "File_Open";

[Mads Ager (google), 2012/03/09 09:40:13]

Do we want 'void' here?

[Søren Gjesse, 2012/03/13 08:25:55]

No, open now returns either an int or an instance of OSError. We could write
Object.

   static bool create(String name) native "File_Create";
   static bool delete(String name) native "File_Delete";
   static String fullPath(String name) native "File_FullPath";
@@ -280,8 +280,14 @@ class _FileUtils {
   static SendPort newServicePort() native "File_NewServicePort";
 
   static int checkedOpen(String name, int mode) {
-    if (name is !String || mode is !int) return 0;
-    return open(name, mode);
+    if (name is !String || mode is !int) {
+      throw new IllegalArgumentException();
+    };
+    var result = open(name, mode);
+    if (result is OSError) {
+      throw new FileIOException("Cannot open file", result);
+    }
+    return result; 
   }
 
   static bool checkedCreate(String name) {
@@ -440,11 +446,14 @@ class _File implements File {
     request[0] = _FileUtils.kOpenRequest;
     request[1] = _name;
     request[2] = mode._mode;  // Direct int value for serialization.
-    _fileService.call(request).receive((id, replyTo) {
-      if (id != 0) {
+    _fileService.call(request).receive((result, replyTo) {
+      if (result is Array) {
+        if (_onError != null) {
+          _onError(new FileIOException(
+              "Cannot open file", new OSError(result[1], result[0])));
+        }
+      } else {
         callback(new _RandomAccessFile(id, _name));
-      } else if (_onError != null) {
-        _onError("Cannot open file: $_name");
       }
     });
   }
@@ -461,9 +470,7 @@ class _File implements File {
                                 "FileMode.WRITE or FileMode.APPEND.");
     }
     var id = _FileUtils.checkedOpen(_name, mode._mode);
-    if (id == 0) {
-      throw new FileIOException("Cannot open file: $_name");
-    }
+    assert(id != 0);
     return new _RandomAccessFile(id, _name);
   }