Bug 10391 - Better handling of anonymous types
Summary: Better handling of anonymous types
Alias: None
Product: Runtime
Classification: Mono
Component: Debugger ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2013-02-18 16:56 UTC by Mikayla Hutchinson [MSFT]
Modified: 2017-07-07 19:09 UTC (History)
6 users (show)

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

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Description Mikayla Hutchinson [MSFT] 2013-02-18 16:56:00 UTC
Anonymous types have auto properties back by a field named "<Foo>" where Foo is the property name.

Currently the debugger shows the fields and the properties, which is redundant. We should treat them like other auto properties - hide the backing field entirely, and make debugger calls to the property get/set the backing field directly.
Comment 1 Marek Safar 2013-02-20 15:45:05 UTC
No need for any special hacking they have DebuggerBrowsable set (at least tested with mono 3.0)
Comment 2 Jeffrey Stedfast 2013-02-20 17:23:04 UTC
For some reason, FieldInfoMirror.GetCustomAttributes (true) is retuning an empty array of CustomAttributeMirrors for fields in anonymous types even though I can clearly see DebuggerBrowsableAttributes in the disassembled IL.

We can probably work around this in MonoDevelop, but it'd be nice if the runtime returned the proper attributes.

I've updated the MonoDevelop logic to shortcut evaluation of the anonymous type's properties by just poking the appropriate field value, though.
Comment 3 Marek Safar 2013-02-21 03:50:37 UTC
I tested simple "var a = new X { foo = 3 } and it worked for me on Mono 3
Comment 4 Zoltan Varga 2013-02-23 17:33:06 UTC
Jeff: I can't reproduce this with master, I can repro with 2.10, but only because mcs doesn't seem to generate the DebuggerBrowsable attribute there.
Comment 5 Zoltan Varga 2013-09-16 15:19:16 UTC
Jeff: Does the problem in #2 still happens ?
Comment 6 Ludovic Henry 2017-07-07 19:09:06 UTC
If you can still reproduce with latest mono version, please feel free to reopen the bug. Thank you.