make SourceLink.dll buildable on Mono

[ctaggart]

Starting where #23 left off, the current error when building on Mono is about missing method for OpenMappedExeConfiguration.

fsharpi -d:MONO build.fsx
Missing method System.Configuration.ConfigurationManager::OpenMappedExeConfiguration(ExeConfigurationFileMap,ConfigurationUserLevel,bool) in assembly /Library/Frameworks/Mono.framework/Versions/3.2.6/lib/mono/gac/System.Configuration/4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll, referenced in assembly /Users/cameron_taggart/Projects/SourceLink4/packages/SourceLink.Fake/tools/SourceLink.dll
System.MissingMethodException: Method not found: 'System.Configuration.ConfigurationManager.OpenMappedExeConfiguration'.

[ctaggart]

Mono 3.2.5 doesn't support ToolsVersion 12.0 or TargetFSharpCoreVersion 4.3.1.0. May have to conditionally enable ToolsVersion 4.0 and TargetFSharpCoreVersion 4.3.0.0.

[ctaggart]

Using Xamarin Studio 4.2.3 (latest stable), it kept corrupting the SourceLink.sln file. I'd often see:

because it put {0} palceholders in where the versions go.

Does Xamarin Studio not work correctly with Visual Studio 2013 .sln files yet?

[ctaggart]

$ mono .nuget/NuGet.exe restore SourceLink.sln not working

[ctaggart]

The current issue running the build script on Mono on Mac OS X is that the git2-b5e9dc6 library is not found.

The static initializer in LibGit2Sharp/Core/NativeMethods.cs has code for adding to the PATH env var on Windows, but I don't see any equivalent for Linux and Mac OS X.

If System.Environment.OSVersion.Platform is Unix, it is possible to detect Mac OS X by seeing if uname = "Darwin".

open System
open System.Runtime.InteropServices

module Libc =
    [<DllImport("libc")>]
    extern int uname (IntPtr buf)

let uname() =
    let buf = Marshal.AllocHGlobal 8192
    let nm = if Libc.uname buf = 0 then Marshal.PtrToStringAnsi buf else ""
    Marshal.FreeHGlobal buf
    nm

[<EntryPoint>]
let main args = 
    let nm = uname()
    printfn "nm: %A" nm
    0

• https://github.com/mono/mono/blob/master/mcs/class/System/System/Platform.cs
• http://stackoverflow.com/questions/8408467/where-is-mono-unix-native
• http://mono.1490590.n4.nabble.com/Detecting-if-platform-is-Mac-td1504460.html

Mono docs on interop with native libraries shows a couple of approaches, but does a .dll extension work or is a .so required?

@nulltoken How do I use LibGit2Sharp on Mac OS X and Linux?

[nulltoken]

@ctaggart You'll have to build the libgit2 binary first. See build.libgit2sharp.sh for some inspiration.

FWIW @ben made sure that LibGit2sharp tests were running on MacOS X (cf. libgit2/libgit2sharp#560)

[ben]

You'll want a .so or a .dylib, and you'll need to modify the LD_LIBRARY_PATH and DY LD_LIBRARY_PATH environment variables so mono can find the native binaries.

[ctaggart]

Would like to see all the native libraries included in the LibGit2Sharp nupkg.

Current error on Travis CI is:

/Users/travis/build/ctaggart/SourceLink/SourceLink/VsProj.fs(15,38): warning FS1125: The instantiation of the generic type 'Dictionary' is missing and can't be inferred from the arguments or return type of this member. Consider providing a type instantiation when accessing this type, e.g. 'Dictionary<_,_>'.

I guess F# 3.1 has improved type inference with generics. It is erroring on this line:
Project(proj, globalProps |> Dictionary.ofTuples, null, pc)

ofTuples may actually need the generics adjusted.

[ctaggart]

I did want CI builds for this project, but I'm going to go with AppVeyor instead #25. Another thing I wanted to make sure of was that adding SourceLink to a project will not prevent you from using Travis CI. FAKE's support for #if MONO, that I helped add, works well. Anything that uses LibGit2Sharp or TFS needs to be #if'd out.