Build script finds the latest version of msbuild, instead of relying …

…on similar logic in psake, as a step towards phasing out psake. Lookup logic adapted from https://github.com/ligershark/psbuild/blob/master/src/psbuild.psm1.

build.ps1

@@ -48,8 +48,9 @@ task Test {
 }
 
 function compile-solution {
-  exec { msbuild /t:clean /v:q /nologo /p:Configuration=$configuration src\Parsley.sln }
-  exec { msbuild /t:build /v:q /nologo /p:Configuration=$configuration src\Parsley.sln }
+    Set-Alias msbuild (get-msbuild-path)
+    exec { msbuild /t:clean /v:q /nologo /p:Configuration=$configuration src\Parsley.sln }
+    exec { msbuild /t:build /v:q /nologo /p:Configuration=$configuration src\Parsley.sln }
 }
 
 function generate-assembly-info {
@@ -115,3 +116,32 @@ function regenerate-file($path, $newContent) {
         [System.IO.File]::WriteAllText($path, $newContent, [System.Text.Encoding]::UTF8)
     }
 }
+
+function get-msbuild-path {
+    [cmdletbinding()]
+    param(
+        [Parameter(Position=0)]
+        [ValidateSet('32bit','64bit')]
+        [string]$bitness = '32bit'
+    )
+    process{
+
+        # Find the highest installed version of msbuild.exe.
+
+        $regLocalKey = $null
+
+        if($bitness -eq '32bit'){
+            $regLocalKey = [Microsoft.Win32.RegistryKey]::OpenBaseKey([Microsoft.Win32.RegistryHive]::LocalMachine,[Microsoft.Win32.RegistryView]::Registry32)
+        } else {
+            $regLocalKey = [Microsoft.Win32.RegistryKey]::OpenBaseKey([Microsoft.Win32.RegistryHive]::LocalMachine,[Microsoft.Win32.RegistryView]::Registry64)
+        }
+
+        $versionKeyName = $regLocalKey.OpenSubKey('SOFTWARE\Microsoft\MSBuild\ToolsVersions\').GetSubKeyNames() | Sort-Object {[double]$_} -Descending
+
+        $keyToReturn = ('SOFTWARE\Microsoft\MSBuild\ToolsVersions\{0}' -f $versionKeyName)
+
+        $path = ( '{0}msbuild.exe' -f $regLocalKey.OpenSubKey($keyToReturn).GetValue('MSBuildToolsPath'))
+
+        return $path
+    }
+}