Fable support

Author: ncave

.gitignore

@@ -191,7 +191,7 @@ artifacts/*.nupkg
 *.orig
 *.mdf
 *.ldf
-.paket/paket.exe
+fcs/.paket/paket.exe
 paket-files
 docsrc/tools/FSharp.Formatting.svclog
 src/fsharp/FSharp.Compiler.Service/pplex.fs
@@ -201,6 +201,7 @@ src/fsharp/FSharp.Compiler.Service/pppars.fsi
 *.cto
 *.vstman
 project.lock.json
+.vscode
 
 src/fsharp/FSharp.Compiler.Service/FSComp.fs
 src/fsharp/FSharp.Compiler.Service/FSComp.resx

fcs/build.fsx

@@ -87,6 +87,10 @@ Target "BuildVersion" (fun _ ->
     Shell.Exec("appveyor", sprintf "UpdateBuild -Version \"%s\"" buildVersion) |> ignore
 )
 
+Target "BuildTools" (fun _ ->
+    runDotnet __SOURCE_DIRECTORY__ "build ../src/buildtools/buildtools.proj -v n -c Proto"
+)
+
 Target "Build" (fun _ ->
     runDotnet __SOURCE_DIRECTORY__ "build ../src/buildtools/buildtools.proj -v n -c Proto"
     runDotnet __SOURCE_DIRECTORY__ "build FSharp.Compiler.Service.sln -v n -c release"
@@ -105,6 +109,25 @@ Target "NuGet" (fun _ ->
     runDotnet __SOURCE_DIRECTORY__ "pack FSharp.Compiler.Service.sln -v n -c release"
 )
 
+Target "CodeGen.Fable" (fun _ ->
+    let outDir = __SOURCE_DIRECTORY__ + "/fcs-fable/codegen/"
+
+    // run FCS codegen (except that fssrgen runs without .resx output to inline it)
+    runDotnet outDir "run -- ../../../src/fsharp/FSComp.txt FSComp.fs"
+    runDotnet outDir "run -- ../../../src/fsharp/fsi/FSIstrings.txt FSIstrings.fs"
+
+    // Fable-specific (comment the #line directive as it is not supported)
+    ["lex.fs"; "pplex.fs"; "illex.fs"; "ilpars.fs"; "pars.fs"; "pppars.fs"]
+    |> Seq.map (fun fileName -> outDir + fileName)
+    |> RegexReplaceInFilesWithEncoding @"(?<!/)# (?=\d)" "//# " Text.Encoding.UTF8
+
+    // prevent stack overflows on large files (make lexer rules inline)
+    let pattern = @"(?<=and )(?!inline )([a-zA-Z]+ )+ *\(lexbuf "
+    ["lex.fs"; "pplex.fs"; "illex.fs"]
+    |> Seq.map (fun fileName -> outDir + fileName)
+    |> RegexReplaceInFilesWithEncoding pattern @"inline $0" Text.Encoding.UTF8
+)
+
 Target "GenerateDocsEn" (fun _ ->
     executeFSIWithArgs "docsrc/tools" "generate.fsx" [] [] |> ignore
 )
@@ -132,6 +155,10 @@ Target "Release" DoNothing
 Target "GenerateDocs" DoNothing
 Target "TestAndNuGet" DoNothing
 
+"Clean"
+  ==> "BuildTools"
+  ==> "CodeGen.Fable"
+
 "Start"
   =?> ("BuildVersion", isAppVeyorBuild)
   ==> "Restore"

fcs/fcs-fable/.gitignore

@@ -0,0 +1,3 @@
+# Codegen
+codegen/*.fs
+codegen/*.fsi