PostSharp

[morphine]

Hello Gael,

I am looking for the quickest way to debug aspects at compile-time using VS 2008. Based on documentation I need to run msbuild with param /P:PostSharpAttachDebugger=true; so I integrated this in VS as an External Tool, and now I have it available in the Tools menu. If anyone is interested in this, here are the steps:

1. Select Tools > External Tools...
2. Click Add and enter the following data:

• Title: Debug PostSharp Aspects [Compile-time]
• Command: %windir%\Microsoft.NET\Framework\v3.5\MSBuild.exe
• Arguments: /T:Rebuild $(ProjectFileName) /P:PostSharpAttachDebugger=true
• Initial Directory: $(ProjectDir)

3. Check Use Output window to display msbuild messages in VS
4. Click OK

As a result, a new menu item has been created in Tools; after clicking it, the workflow is as follows:

• PostSharp process throws exception "Launch for user" which is displayed in VS JIT
• From the list of possible debuggers, select the VS instance in which the project is loaded and click Yes
• if VS displays a message box complaining "No symbols are loaded for any call stack frame. The source code cannot be displayed.", just click OK.
• add breakpoints in aspect's compile-time logic, if you haven't already done it
• press F5 to start debugging; if breakpoints were added correctly, they will be hit

The question is: is there a faster way to achieve this? What I would like to do is:

• define a build configuration for my project: "debug aspects"
• define compilation symbol "PostSharpAttachDebugger"
  (although it would be cool if these would be available out of the box, if the project references any PostSharp assembly)
• select the newly defined configuration and hit F5; when I do this, the debugger attaches to PostSharp process automatically and, after this one exits, it reattaches to the original process...

Truth be told, I do not know if this behavior is even possible... but it would be very cool if so

[gfraiteur]

Hi Morphine,

Thank you for your contribution.


Detecting a compilation symbol "PostSharpAttachDebugger" would be possible, but I don't think it would be useful.

Another possibility is to put aspects in an separate assembly, and to configure the debugger (Project Properties / Debugger) to run msbuild as an external program. You should then use the flag

Code: Select all

/p:PostSharpUseCommandLine=False

, otherwise PostSharp will execute in a different process than MSBuild and you won't be able to set breakpoints.

So, use the following command line:

Code: Select all


C:\Windows\Microsoft.NET\Framework\v....\msbuild.exe ..\AspectTest.csproj /t:Rebuild /p:PostSharpUseCommandLine=false



Set the aspect project as the startup project, then use F5 as usually.

[morphine]

Hi Gael,

I did as you suggested: created a class library for my aspects and tried to debug it using msbuild as external program; it didn't work Passing the dll as argument to msbuild yields error "Data at the root level is invalid. Line 1, position 1."; I am no msbuild expert, but I can recognize an XmlException and that's exactly what I got here, as msbuild expects a well-formed XML as input which should be my .csproj, not the assembly, right?

I made some investigations and found another way, although way too complicated: using postsharp.exe as external program, with the same arguments as the ones received usually by Exec task (that huge long command line, I copied it from msbuild's output) Worked like a charm, no more popups but I don't feel comfortable with all arguments "hard-coded"...so I stick to the external tool for now.

[gfraiteur]

Sure, you had to pass the csproj to msbuild, not the dll. My mistake. I will edit my previous post.

[morphine]

Hi,

This doesn't work, I get these exceptions on build:

Unhandled exception: PostSharp.CodeModel.BindingException: Error while loading the assembly "obj\Debug\Before-PostSharp\MyAspects.dll": Absolute path information is required.

===== PostSharp Assembly Binder =================

Loading assembly from file {obj\Debug\Before-PostSharp\MyAspects.dll}.

System.ArgumentException: Absolute path information is required.

The post build event is:

Code: Select all

C:\Windows\Microsoft.NET\Framework\v3.5\msbuild.exe "$(ProjectPath)" /t:Rebuild /p:PostSharpUseCommandLine=false

Suppose it builds: the command should not do more than displaying messages in VS's output window rather in system's console; since I want to be able to debug the thing, I should add /p=PostSharpAttachDebugger=true, right? I did this and got VS JIT popup, only that this time it only displays "New instance of VS", which I cannot use.

Even worse: clicking No on the popup window seems to run the post build event again without closing the msbuild process, so I ended up having plenty of msbuild.exe processes in task manager; the only way to shut them down was to end process tree.