Referencing an assembly in a T4 template

Question

It's been a while since I last used T4 and this is probably a silly question...

Is it possible to reference an arbitrary assembly from a template?

Example:

• I have a class that I'd like to use in Project X
• Project X.Test references X and contains the .tt file

I assume the following should work

<#@ assembly name="X" #>

But I get the following error on save:

Compiling transformation: Metadata file 'X' could not be found

What am I doing wrong?

(In case anyone's interested: I'm trying to automatically generate a particular type of tests based on some metadata that I get from X)

Update: it looks like VS2010 has broken the assembly resolution behavior that I was expecting. From Link:

T4's assembly set is completely separated from the containing project's assembly set to avoid picking up the wrong assemblies when a project targets previous framework versions. Project assemblies are no longer used to resolve template assembly directives.

Are there any workarounds, besides using absolute paths?

Loess

Have you tried using the fully qualified path for that assembly? The text templating tool is an external tool and probably doesn't know about projects you have loaded into VS. – Miliaria

That works, but I need this to run in multiple machines that might have the project in a different path. – Loess

Answer 1

You can use VS macro variables such as $(SolutionDir) in your reference as of VS2010 e.g.

<#@ assembly name="$(SolutionDir)\Project1\bin\debug\Foo.dll" #>

Preparative

This isn't working for me. Any ideas on what I'm doing wrong? My assembly ref is as follows: <#@ assembly name="$(SolutionDir)\DataObjects\bin\Debug\DataObjects.dll" #> – Anabaptist

That shoudl work just fine, but it sounds from the otehr threads liek you are using VS 2008, not VS2010? If you're usign VS2008, the recommended approach is to add the assembly as a project reference in the hosting project instead. – Preparative

+1 very useful. I had to reference the current assembly and used the following <#@ assembly name="$(TargetPath)"#> – Billybillycock

How about when editing the scaffolding tts in Mvc? MVCWebApplication1\CodeTemplates\AddView\CSHTML\Edit.tt. Get folowing to work in a simple .tt but not in Edit.tt: <#@ assembly name="$(TargetDir)\ToSpinitLibraryModel.dll"#> Also tried via "$(SolutionDir) – Gubernatorial

No, I'm afraid not, as that uses a different host at present. You could log a connect bug or post on asp.net uservoice to request this. – Preparative

Answer 2

You can also check here on SO: Can't reference an assembly in a T4 template

Nibbs

Answer 3

@GarethJ gives a good answer but for all the methods of referencing an assembly from a T4 template try this: T4 Template error - Assembly Directive cannot locate referenced assembly in Visual Studio 2010 project.

And if you like the VS Macro solution then you can find 'em all here: Macros for Build Commands and Properties

Udometer