Bug 2169 - ObservableCollection's constructor is incorrect
Summary: ObservableCollection's constructor is incorrect
Alias: None
Product: Class Libraries
Classification: Mono
Component: WindowsBase ()
Version: 2.10.x
Hardware: PC Windows
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2011-11-23 09:23 UTC by Anonymous
Modified: 2011-11-24 08:00 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Anonymous 2011-11-23 09:23:42 UTC
The constructor
public ObservableCollection(List<T> list)
has an incorrect implementation: it only passes the source list to its base (which is Collection<>).

As read in the DotNet documentation, and tested in reality, this constructor should create a new list and duplicate the items (one by one) of the source list.

The practical difference is that in the current Mono implementation we have only one list with two references, but in DotNet we have two different lists.
So a program based on this wrong assumption can work fine in Mono but not in dotnet.
That provoked a bug in my program, for example.

See here for more info: http://msdn.microsoft.com/en-us/library/ms653202
"The elements are *copied* onto the ObservableCollection(Of T) in the same order they are read by the enumerator of the list."
Comment 1 Marek Safar 2011-11-24 08:00:19 UTC
Fixed in master