Use source-map-sharp

.gitignore

@@ -4,6 +4,7 @@
 node_modules/
 temp/
 *.fs.js
+*.fs.js.map
 src/fable-library/*.js
 src/fable-library/BigInt/*.js
 

src/Fable.Cli/Entry.fs

@@ -53,6 +53,7 @@ Arguments:
   --cwd             Working directory
   -o|--outDir       Redirect compilation output to a directory
   --extension       Extension for generated JS files (default .fs.js)
+  -s|--sourceMaps   Enable source maps
 
   --define          Defines a symbol for use in conditional compilation
   --verbose         Print more info during compilation
@@ -159,6 +160,7 @@ type Runner =
               FableLibraryPath = argValue "--fableLib" args
               RootDir = rootDir
               OutDir = argValueMulti ["-o"; "--outDir"] args |> Option.map normalizeAbsolutePath
+              SourceMaps = flagEnabled "-s" args || flagEnabled "--sourceMaps" args
               ForcePkgs = flagEnabled "--forcePkgs" args
               NoRestore = flagEnabled "--noRestore" args
               Exclude = argValue "--exclude" args
@@ -190,7 +192,7 @@ let clean args dir =
         argValue "--extension" args |> Option.defaultValue (defaultFileExt typescript args)
 
     // clean is a potentially destructive operation, we need a permission before proceeding
-    Console.WriteLine("This will recursively delete all *{0} files in {1}", fileExt, dir)
+    Console.WriteLine("This will recursively delete all *{0}[.map] files in {1}", fileExt, dir)
     if not(flagEnabled "--yes" args) then
         Console.WriteLine("Please press 'Y' or 'y' if you want to continue: ")
         let keyInfo = Console.ReadKey()
@@ -201,8 +203,11 @@ let clean args dir =
 
     let mutable fileCount = 0
     let rec recClean dir =
-        IO.Directory.GetFiles(dir, "*" + fileExt)
-        |> Array.iter (fun file ->
+        seq {
+            yield! IO.Directory.GetFiles(dir, "*" + fileExt)
+            yield! IO.Directory.GetFiles(dir, "*" + fileExt + ".map")
+        }
+        |> Seq.iter (fun file ->
             IO.File.Delete(file)
             fileCount <- fileCount + 1
             Log.verbose(lazy ("Deleted " + file)))

src/Fable.Cli/Fable.Cli.fsproj

@@ -3,8 +3,8 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFramework>netcoreapp3.1</TargetFramework>
-    <Version>3.0.5</Version>
-    <PackageVersion>3.0.5</PackageVersion>
+    <Version>3.1.0</Version>
+    <PackageVersion>3.1.0-beta-001</PackageVersion>
     <!-- Allow users with newer dotnet SDK to run Fable, see #1910 -->
     <RollForward>Major</RollForward>
     <DisableImplicitFSharpCoreReference>true</DisableImplicitFSharpCoreReference>
@@ -37,6 +37,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Dotnet.ProjInfo" Version="0.44.0" />
+    <PackageReference Include="source-map-sharp" Version="1.0.2" />
     <!-- <PackageReference Include="FSharp.Core" Version="5.0.0" /> -->
   </ItemGroup>
 </Project>

src/Fable.Cli/Main.fs

@@ -160,10 +160,27 @@ module private Util =
                 |> FableTransforms.transformFile com
                 |> Fable2Babel.Compiler.transformFile com
 
-            // TODO: Dummy interface until we have a dotnet port of SourceMapGenerator
-            // https://github.com/mozilla/source-map#with-sourcemapgenerator-low-level-api
-            let map = { new BabelPrinter.SourceMapGenerator with
-                            member _.AddMapping(_,_,_,_,_) = () }
+            let mapPrinter, mapGen =
+                if cliArgs.SourceMaps then
+                    let mapGenerator = SourceMapSharp.SourceMapGenerator()
+
+                    let print outPath = async {
+                        let mapPath = outPath + ".map"
+                        do! IO.File.AppendAllLinesAsync(outPath, [$"//# sourceMappingURL={IO.Path.GetFileName(mapPath)}"]) |> Async.AwaitTask
+                        use sw = IO.File.OpenWrite(mapPath)
+                        do! Text.Json.JsonSerializer.SerializeAsync(sw, mapGenerator.toJSON()) |> Async.AwaitTask
+                    }
+
+                    print, { new BabelPrinter.SourceMapGenerator with
+                        member _.AddMapping(orLine, orCol, genLine, genCol, name) =
+                            let generated: SourceMapSharp.Util.MappingIndex =
+                                {line = genLine; column = genCol}
+                            let original: SourceMapSharp.Util.MappingIndex =
+                                {line = orLine; column = orCol}
+                            mapGenerator.AddMapping(generated, original, source=com.CurrentFile, ?name=name) }
+                else
+                    Async.ignore, { new BabelPrinter.SourceMapGenerator with
+                        member _.AddMapping(_,_,_,_,_) = () }
 
             let outPath = getOutJsPath cliArgs dedupTargetDir com.CurrentFile
 
@@ -173,7 +190,8 @@ module private Util =
 
             // write output to file
             let writer = new FileWriter(com.CurrentFile, outPath, cliArgs, dedupTargetDir)
-            do! BabelPrinter.run writer map babel
+            do! BabelPrinter.run writer mapGen babel
+            do! mapPrinter outPath
 
             Log.always("Compiled " + File.getRelativePathFromCwd com.CurrentFile)
 

src/Fable.Cli/RELEASE_NOTES.md

@@ -1,3 +1,8 @@
+### 3.1.0-beta-001
+
+* Source map support @delneg
+* Fix #2332: watch broken for certain directory structures @jwosty
+
 ### 3.0.5
 
 * Fixed compiler option parsing @ncave

src/Fable.Cli/Util.fs

@@ -15,6 +15,7 @@ type CliArgs =
       FableLibraryPath: string option
       ForcePkgs: bool
       NoRestore: bool
+      SourceMaps: bool
       Exclude: string option
       Replace: Map<string, string>
       RunProcess: RunProcess option
@@ -211,6 +212,10 @@ module Async =
                 disp.Dispose()
                 onSuccess(v)))
 
+    let ignore (_: 'a) = async {
+        return ()
+    }
+
 module Imports =
     open Fable
 

src/Fable.Transforms/Global/Compiler.fs

@@ -1,7 +1,7 @@
 namespace Fable
 
 module Literals =
-    let [<Literal>] VERSION = "3.0.5"
+    let [<Literal>] VERSION = "3.1.0-beta-001"
 
 type CompilerOptionsHelper =
     static member DefaultExtension = ".fs.js"