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f#nunitcililasm

Is there a way to run ILASM from F# code?


I am making a compiler from (a small subset of) Java to CIL (MSIL) in F# and I was thinking about writing some unit tests for the actual compilation part. Is there a way I could run ilasm on the generated IL code and the run the .exe file from a unit test? I am using NUnit.

Concretely, is there a way to do the following?

[<Test>]
member this.TestSimpleMain () = 
            let fileName = __SOURCE_DIRECTORY__.Replace("code", "examples\SimpleMain.cil")
            // run ilasm on fileName -> should produce ...\SimpleMain.exe
            let actualResult = // run ...\SimpleMain.exe file
            Assert.That(actualResult , Is.EqualTo("Program returned value 5!")))

Solution

  • If you want to use ilasm make sure you create SimpleMain.cil in IL assembly format (text representation of CIL). Then you should create PE (exe/dll) file from your il file.

    here is an example for the nunit test with output and exit code verification:

    [<Test>]
    member this.TestSimpleMain() =
        // Code that creates SimpleMain.il
    
        let p1 = new System.Diagnostics.Process()
        p1.StartInfo.FileName <- "C:/Windows/Microsoft.NET/Framework64/v4.0.30319/ilasm.exe"
        p1.StartInfo.Arguments <- "SimpleMain.il /exe /output=SimpleMain.exe"
        p1.Start()
        p1.WaitForExit()
    
        let p2 = new System.Diagnostics.Process()
        p2.StartInfo.FileName <- "SimpleMain.exe"
        p2.StartInfo.RedirectStandardOutput <- true // For output verification
        p2.Start()
        p2.WaitForExit()
    
        let resultA = p2.ExitCode // For exit code verification
        let resultB = p2.StandardOutput.ReadToEnd() // For output verification
        Assert.That(result, Is.EqualTo(expectedResult))