Handle URI in arg parser (#240)

.fantomasignore

@@ -0,0 +1 @@
+.direnv/

.gitignore

@@ -11,3 +11,4 @@ result
 analysis.sarif
 .direnv/
 .venv/
+.vs/

CHANGELOG.md

@@ -1,5 +1,9 @@
 Notable changes are recorded here.
 
+# WoofWare.Myriad.Plugins 2.2.1, WoofWare.Myriad.Plugins.Attributes 3.2.1
+
+New generator: `ArgParser`, a basic reflection-free argument parser.
+
 # WoofWare.Myriad.Plugins 2.1.45, WoofWare.Myriad.Plugins.Attributes 3.1.7
 
 The NuGet packages are now attested to through [GitHub Attestations](https://github.blog/2024-05-02-introducing-artifact-attestations-now-in-public-beta/).

ConsumePlugin/Args.fs

@@ -93,3 +93,45 @@ type DatesAndTimes =
         [<InvariantCulture ; ParseExact @"hh\:mm\:ss">]
         InvariantExact : TimeSpan
     }
+
+type ChildRecord =
+    {
+        Thing1 : int
+        Thing2 : string
+    }
+
+[<ArgParser true>]
+type ParentRecord =
+    {
+        Child : ChildRecord
+        AndAnother : bool
+    }
+
+type ChildRecordWithPositional =
+    {
+        Thing1 : int
+        [<PositionalArgs>]
+        Thing2 : Uri list
+    }
+
+[<ArgParser true>]
+type ParentRecordChildPos =
+    {
+        Child : ChildRecordWithPositional
+        AndAnother : bool
+    }
+
+[<ArgParser true>]
+type ParentRecordSelfPos =
+    {
+        Child : ChildRecord
+        [<PositionalArgs>]
+        AndAnother : bool list
+    }
+
+[<ArgParser true>]
+type ChoicePositionals =
+    {
+        [<PositionalArgs>]
+        Args : Choice<string, string> list
+    }

WoofWare.Myriad.Plugins.Attributes/Test/WoofWare.Myriad.Plugins.Attributes.Test.fsproj

@@ -5,6 +5,11 @@
 
       <IsPackable>false</IsPackable>
       <IsTestProject>true</IsTestProject>
+      <!--
+        Known high severity vulnerability
+        I have not yet seen a single instance where I care about this warning
+      -->
+      <NoWarn>$(NoWarn),NU1903</NoWarn>
     </PropertyGroup>
 
     <ItemGroup>

WoofWare.Myriad.Plugins.Test/TestArgParser/TestArgParser.fs

@@ -341,3 +341,94 @@ Input string was not in a correct format. (at arg --exact=11:34)
 Required argument '--exact' received no value"""
 
         count.Value |> shouldEqual 0
+
+    [<Test>]
+    let ``Can consume stacked record without positionals`` () =
+        let getEnvVar (_ : string) = failwith "should not call"
+
+        let parsed =
+            ParentRecord.parse' getEnvVar [ "--and-another=true" ; "--thing1=9" ; "--thing2=a thing!" ]
+
+        parsed
+        |> shouldEqual
+            {
+                Child =
+                    {
+                        Thing1 = 9
+                        Thing2 = "a thing!"
+                    }
+                AndAnother = true
+            }
+
+    [<Test>]
+    let ``Can consume stacked record, child has positionals`` () =
+        let getEnvVar (_ : string) = failwith "should not call"
+
+        let parsed =
+            ParentRecordChildPos.parse'
+                getEnvVar
+                [
+                    "--and-another=true"
+                    "--thing1=9"
+                    "--thing2=https://example.com"
+                    "--thing2=http://example.com"
+                ]
+
+        parsed.AndAnother |> shouldEqual true
+        parsed.Child.Thing1 |> shouldEqual 9
+
+        parsed.Child.Thing2
+        |> List.map (fun (x : Uri) -> x.ToString ())
+        |> shouldEqual [ "https://example.com/" ; "http://example.com/" ]
+
+    [<Test>]
+    let ``Can consume stacked record, child has no positionals, parent has positionals`` () =
+        let getEnvVar (_ : string) = failwith "should not call"
+
+        let parsed =
+            ParentRecordSelfPos.parse'
+                getEnvVar
+                [
+                    "--and-another=true"
+                    "--and-another=false"
+                    "--and-another=true"
+                    "--thing1=9"
+                    "--thing2=some"
+                ]
+
+        parsed
+        |> shouldEqual
+            {
+                Child =
+                    {
+                        Thing1 = 9
+                        Thing2 = "some"
+                    }
+                AndAnother = [ true ; false ; true ]
+            }
+
+    [<Test>]
+    let ``Help text for stacked records`` () =
+        let getEnvVar (_ : string) = failwith "should not call"
+
+        let exc =
+            Assert.Throws<exn> (fun () ->
+                ParentRecordSelfPos.parse' getEnvVar [ "--help" ] |> ignore<ParentRecordSelfPos>
+            )
+
+        exc.Message
+        |> shouldEqual
+            """Help text requested.
+--thing1  int32
+--thing2  string
+--and-another  bool (positional args) (can be repeated)"""
+
+    [<Test>]
+    let ``Positionals are tagged with Choice`` () =
+        let getEnvVar (_ : string) = failwith "should not call"
+
+        ChoicePositionals.parse' getEnvVar [ "a" ; "b" ; "--" ; "--c" ; "--help" ]
+        |> shouldEqual
+            {
+                Args = [ Choice1Of2 "a" ; Choice1Of2 "b" ; Choice2Of2 "--c" ; Choice2Of2 "--help" ]
+            }

WoofWare.Myriad.Plugins.Test/WoofWare.Myriad.Plugins.Test.fsproj

@@ -4,6 +4,11 @@
     <TargetFramework>net8.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <IsTestProject>true</IsTestProject>
+    <!--
+      Known high severity vulnerability
+      I have not yet seen a single instance where I care about this warning
+    -->
+    <NoWarn>$(NoWarn),NU1903</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>

WoofWare.Myriad.Plugins/ArgParserGenerator.fs

@@ -22,13 +22,13 @@ type private ArgumentDefaultSpec =
     /// we would use `MyArgs.DefaultThing () : int`.
     | FunctionCall of name : Ident
 
-type private Accumulation =
+type private Accumulation<'choice> =
     | Required
     | Optional
-    | Choice of ArgumentDefaultSpec
-    | List
+    | Choice of 'choice
+    | List of Accumulation<'choice>
 
-type private ParseFunction =
+type private ParseFunction<'acc> =
     {
         FieldName : Ident
         TargetVariable : Ident
@@ -42,20 +42,183 @@ type private ParseFunction =
         /// If `Accumulation` is `List`, then this is the type of the list *element*; analogously for optionals
         /// and choices and so on.
         TargetType : SynType
-        Accumulation : Accumulation
+        Accumulation : 'acc
     }
 
+[<RequireQualifiedAccess>]
+type private ChoicePositional =
+    | Normal
+    | Choice
+
+type private ParseFunctionPositional = ParseFunction<ChoicePositional>
+type private ParseFunctionNonPositional = ParseFunction<Accumulation<ArgumentDefaultSpec>>
+
 type private ParserSpec =
     {
-        NonPositionals : ParseFunction list
+        NonPositionals : ParseFunctionNonPositional list
         /// The variable into which positional arguments will be accumulated.
         /// In this case, the TargetVariable is a `ResizeArray` rather than the usual `option`.
-        Positionals : ParseFunction option
+        Positionals : ParseFunctionPositional option
     }
 
-type private ArgToParse =
-    | Positional of ParseFunction
-    | NonPositional of ParseFunction
+type private HasPositional = HasPositional
+type private HasNoPositional = HasNoPositional
+
+[<AutoOpen>]
+module private TeqUtils =
+    let exFalso<'a> (_ : Teq<HasNoPositional, HasPositional>) : 'a = failwith "LOGIC ERROR!"
+    let exFalso'<'a> (_ : Teq<HasPositional, HasNoPositional>) : 'a = failwith "LOGIC ERROR!"
+
+[<RequireQualifiedAccess>]
+type private ParseTree<'hasPositional> =
+    | NonPositionalLeaf of ParseFunctionNonPositional * Teq<'hasPositional, HasNoPositional>
+    | PositionalLeaf of ParseFunctionPositional * Teq<'hasPositional, HasPositional>
+    /// `assemble` takes the SynExpr's (e.g. each record field contents) corresponding to each `Ident` in
+    /// the branch (e.g. each record field name),
+    /// and composes them into a `SynExpr` (e.g. the record-typed object).
+    | Branch of
+        fields : (Ident * ParseTree<HasNoPositional>) list *
+        assemble : (Map<string, SynExpr> -> SynExpr) *
+        Teq<'hasPositional, HasNoPositional>
+    /// `assemble` takes the SynExpr's (e.g. each record field contents) corresponding to each `Ident` in
+    /// the branch (e.g. each record field name),
+    /// and composes them into a `SynExpr` (e.g. the record-typed object).
+    | BranchPos of
+        posField : Ident *
+        fields : ParseTree<HasPositional> *
+        (Ident * ParseTree<HasNoPositional>) list *
+        assemble : (Map<string, SynExpr> -> SynExpr) *
+        Teq<'hasPositional, HasPositional>
+
+type private ParseTreeEval<'ret> =
+    abstract Eval<'a> : ParseTree<'a> -> 'ret
+
+type private ParseTreeCrate =
+    abstract Apply<'ret> : ParseTreeEval<'ret> -> 'ret
+
+[<RequireQualifiedAccess>]
+module private ParseTreeCrate =
+    let make<'a> (p : ParseTree<'a>) =
+        { new ParseTreeCrate with
+            member _.Apply a = a.Eval p
+        }
+
+[<RequireQualifiedAccess>]
+module private ParseTree =
+    [<RequireQualifiedAccess>]
+    type State =
+        | Positional of ParseTree<HasPositional> * ParseTree<HasNoPositional> list
+        | NoPositional of ParseTree<HasNoPositional> list
+
+    let private cast (t : Teq<'a, 'b>) : Teq<ParseTree<'a>, ParseTree<'b>> = Teq.Cong.believeMe t
+
+    /// The `Ident` here is the field name.
+    let branch (assemble : Map<string, SynExpr> -> SynExpr) (subs : (Ident * ParseTreeCrate) list) : ParseTreeCrate =
+        let rec go
+            (selfIdent : Ident option)
+            (acc : (Ident * ParseTree<HasNoPositional>) list, pos : (Ident * ParseTree<HasPositional>) option)
+            (subs : (Ident * ParseTreeCrate) list)
+            : ParseTreeCrate
+            =
+            match subs with
+            | [] ->
+                match pos with
+                | None -> ParseTree.Branch (List.rev acc, assemble, Teq.refl) |> ParseTreeCrate.make
+                | Some (posField, pos) ->
+                    ParseTree.BranchPos (posField, pos, List.rev acc, assemble, Teq.refl)
+                    |> ParseTreeCrate.make
+            | (fieldName, sub) :: subs ->
+                { new ParseTreeEval<_> with
+                    member _.Eval (t : ParseTree<'a>) =
+                        match t with
+                        | ParseTree.NonPositionalLeaf (_, teq)
+                        | ParseTree.Branch (_, _, teq) ->
+                            go selfIdent (((fieldName, Teq.cast (cast teq) t) :: acc), pos) subs
+                        | ParseTree.PositionalLeaf (_, teq)
+                        | ParseTree.BranchPos (_, _, _, _, teq) ->
+                            match pos with
+                            | None -> go selfIdent (acc, Some (fieldName, Teq.cast (cast teq) t)) subs
+                            | Some (ident, _) ->
+                                failwith
+                                    $"Multiple entries tried to claim positional args! %s{ident.idText} and %s{fieldName.idText}"
+                }
+                |> sub.Apply
+
+        go None ([], None) subs
+
+    let rec accumulatorsNonPos (tree : ParseTree<HasNoPositional>) : ParseFunctionNonPositional list =
+        match tree with
+        | ParseTree.PositionalLeaf (_, teq) -> exFalso teq
+        | ParseTree.BranchPos (_, _, _, _, teq) -> exFalso teq
+        | ParseTree.NonPositionalLeaf (pf, _) -> [ pf ]
+        | ParseTree.Branch (trees, _, _) -> trees |> List.collect (snd >> accumulatorsNonPos)
+
+    /// Returns the positional arg separately.
+    let rec accumulatorsPos
+        (tree : ParseTree<HasPositional>)
+        : ParseFunctionNonPositional list * ParseFunctionPositional
+        =
+        match tree with
+        | ParseTree.PositionalLeaf (pf, _) -> [], pf
+        | ParseTree.NonPositionalLeaf (_, teq) -> exFalso' teq
+        | ParseTree.Branch (_, _, teq) -> exFalso' teq
+        | ParseTree.BranchPos (_, tree, trees, _, _) ->
+            let nonPos = trees |> List.collect (snd >> accumulatorsNonPos)
+
+            let nonPos2, pos = accumulatorsPos tree
+            nonPos @ nonPos2, pos
+
+    /// Collect all the ParseFunctions which are necessary to define variables, throwing away
+    /// all information relevant to composing the resulting variables into records.
+    /// Returns the list of non-positional parsers, and any positional parser that exists.
+    let accumulators<'a> (tree : ParseTree<'a>) : ParseFunctionNonPositional list * ParseFunctionPositional option =
+        // Sad duplication of some code here, but it was the easiest way to make it type-safe :(
+        match tree with
+        | ParseTree.PositionalLeaf (pf, _) -> [], Some pf
+        | ParseTree.NonPositionalLeaf (pf, _) -> [ pf ], None
+        | ParseTree.Branch (trees, _, _) -> trees |> List.collect (snd >> accumulatorsNonPos) |> (fun i -> i, None)
+        | ParseTree.BranchPos (_, tree, trees, _, _) ->
+            let nonPos = trees |> List.collect (snd >> accumulatorsNonPos)
+
+            let nonPos2, pos = accumulatorsPos tree
+            nonPos @ nonPos2, Some pos
+
+        |> fun (nonPos, pos) ->
+            let duplicateArgs =
+                Option.toList (pos |> Option.map _.ArgForm) @ (nonPos |> List.map _.ArgForm)
+                |> List.groupBy id
+                |> List.choose (fun (key, v) -> if v.Length > 1 then Some key else None)
+
+            match duplicateArgs with
+            | [] -> nonPos, pos
+            | dups ->
+                let dups = dups |> String.concat " "
+                failwith $"Duplicate args detected! %s{dups}"
+
+    /// Build the return value.
+    let rec instantiate<'a> (tree : ParseTree<'a>) : SynExpr =
+        match tree with
+        | ParseTree.NonPositionalLeaf (pf, _) -> SynExpr.createIdent' pf.TargetVariable
+        | ParseTree.PositionalLeaf (pf, _) -> SynExpr.createIdent' pf.TargetVariable
+        | ParseTree.Branch (trees, assemble, _) ->
+            trees
+            |> List.map (fun (fieldName, contents) ->
+                let instantiated = instantiate contents
+                fieldName.idText, instantiated
+            )
+            |> Map.ofList
+            |> assemble
+        | ParseTree.BranchPos (posField, tree, trees, assemble, _) ->
+            let withPos = instantiate tree
+
+            trees
+            |> List.map (fun (fieldName, contents) ->
+                let instantiated = instantiate contents
+                fieldName.idText, instantiated
+            )
+            |> Map.ofList
+            |> Map.add posField.idText withPos
+            |> assemble
 
 [<RequireQualifiedAccess>]
 module internal ArgParserGenerator =
@@ -77,11 +240,12 @@ module internal ArgParserGenerator =
     /// for example, maybe it returns a `ty option` or a `ty list`).
     /// The resulting SynType is the type of the *element* being parsed; so if the Accumulation is List, the SynType
     /// is the list element.
-    let rec private createParseFunction
+    let rec private createParseFunction<'choice>
+        (choice : ArgumentDefaultSpec option -> 'choice)
         (fieldName : Ident)
         (attrs : SynAttribute list)
         (ty : SynType)
-        : SynExpr * Accumulation * SynType
+        : SynExpr * Accumulation<'choice> * SynType
         =
         match ty with
         | String -> SynExpr.createLambda "x" (SynExpr.createIdent "x"), Accumulation.Required, SynType.string
@@ -93,6 +257,12 @@ module internal ArgParserGenerator =
                     (SynExpr.createIdent "x")),
             Accumulation.Required,
             ty
+        | Uri ->
+            SynExpr.createLambda
+                "x"
+                (SynExpr.applyFunction (SynExpr.createLongIdent [ "System" ; "Uri" ]) (SynExpr.createIdent "x")),
+            Accumulation.Required,
+            ty
         | TimeSpan ->
             let parseExact =
                 attrs
@@ -164,7 +334,7 @@ module internal ArgParserGenerator =
             Accumulation.Required,
             ty
         | OptionType eltTy ->
-            let parseElt, acc, childTy = createParseFunction fieldName attrs eltTy
+            let parseElt, acc, childTy = createParseFunction choice fieldName attrs eltTy
 
             match acc with
             | Accumulation.Optional ->
@@ -173,7 +343,7 @@ module internal ArgParserGenerator =
             | Accumulation.Choice _ ->
                 failwith
                     $"ArgParser does not support optionals containing choices at field %s{fieldName.idText}: %O{ty}"
-            | Accumulation.List ->
+            | Accumulation.List _ ->
                 failwith $"ArgParser does not support optional lists at field %s{fieldName.idText}: %O{ty}"
             | Accumulation.Required -> parseElt, Accumulation.Optional, childTy
         | ChoiceType elts ->
@@ -183,13 +353,13 @@ module internal ArgParserGenerator =
                     failwith
                         $"ArgParser was unable to prove types %O{elt1} and %O{elt2} to be equal in a Choice. We require them to be equal."
 
-                let parseElt, acc, childTy = createParseFunction fieldName attrs elt1
+                let parseElt, acc, childTy = createParseFunction choice fieldName attrs elt1
 
                 match acc with
                 | Accumulation.Optional ->
                     failwith
                         $"ArgParser does not support choices containing options at field %s{fieldName.idText}: %O{ty}"
-                | Accumulation.List ->
+                | Accumulation.List _ ->
                     failwith
                         $"ArgParser does not support choices containing lists at field %s{fieldName.idText}: %O{ty}"
                 | Accumulation.Choice _ ->
@@ -227,43 +397,39 @@ module internal ArgParserGenerator =
 
                 let relevantAttr =
                     match relevantAttrs with
-                    | [] ->
-                        failwith
-                            $"Expected Choice to be annotated with ArgumentDefaultFunction or similar, but it was not. Field: %s{fieldName.idText}"
-                    | [ x ] -> x
+                    | [] -> None
+                    | [ x ] -> Some x
                     | _ ->
                         failwith
-                            $"Expected Choice to be annotated with exactly one ArgumentDefaultFunction or similar, but it was annotated with multiple. Field: %s{fieldName.idText}"
+                            $"Expected Choice to be annotated with at most one ArgumentDefaultFunction or similar, but it was annotated with multiple. Field: %s{fieldName.idText}"
 
-                parseElt, Accumulation.Choice relevantAttr, childTy
+                parseElt, Accumulation.Choice (choice relevantAttr), childTy
             | elts ->
                 let elts = elts |> List.map string<SynType> |> String.concat ", "
 
                 failwith
                     $"ArgParser requires Choice to be of the form Choice<'a, 'a>; that is, two arguments, both the same. For field %s{fieldName.idText}, got: %s{elts}"
         | ListType eltTy ->
-            let parseElt, acc, childTy = createParseFunction fieldName attrs eltTy
+            let parseElt, acc, childTy = createParseFunction choice fieldName attrs eltTy
 
-            match acc with
-            | Accumulation.List ->
-                failwith $"ArgParser does not support nested lists at field %s{fieldName.idText}: %O{ty}"
-            | Accumulation.Choice _ ->
-                failwith $"ArgParser does not support lists containing choices at field %s{fieldName.idText}: %O{ty}"
-            | Accumulation.Optional ->
-                failwith $"ArgParser does not support lists of options at field %s{fieldName.idText}: %O{ty}"
-            | Accumulation.Required -> parseElt, Accumulation.List, childTy
+            parseElt, Accumulation.List acc, childTy
         | _ -> failwith $"Could not decide how to parse arguments for field %s{fieldName.idText} of type %O{ty}"
 
-    let private toParseSpec (finalRecord : RecordType) : ParserSpec =
+    let rec private toParseSpec
+        (counter : int)
+        (ambientRecords : RecordType list)
+        (finalRecord : RecordType)
+        : ParseTreeCrate * int
+        =
         finalRecord.Fields
         |> List.iter (fun (SynField.SynField (isStatic = isStatic)) ->
             if isStatic then
                 failwith "No static record fields allowed in ArgParserGenerator"
         )
 
-        let args : ArgToParse list =
-            finalRecord.Fields
-            |> List.map (fun (SynField.SynField (attrs, _, identOption, fieldType, _, _, _, _, _)) ->
+        let counter, contents =
+            ((counter, []), finalRecord.Fields)
+            ||> List.fold (fun (counter, acc) (SynField.SynField (attrs, _, identOption, fieldType, _, _, _, _, _)) ->
                 let attrs = attrs |> List.collect (fun a -> a.Attributes)
 
                 let positionalArgAttr =
@@ -313,77 +479,110 @@ module internal ArgParserGenerator =
                     | None -> failwith "expected args field to have a name, but it did not"
                     | Some i -> i
 
-                let parser, accumulation, parseTy = createParseFunction ident attrs fieldType
+                let ambientRecordMatch =
+                    match fieldType with
+                    | SynType.LongIdent (SynLongIdent.SynLongIdent (id, _, _)) ->
+                        let target = List.last(id).idText
+                        ambientRecords |> List.tryFind (fun r -> r.Name.idText = target)
+                    | _ -> None
+
+                match ambientRecordMatch with
+                | Some ambient ->
+                    // This field has a type we need to obtain from parsing another record.
+                    let spec, counter = toParseSpec counter ambientRecords ambient
+                    counter, (ident, spec) :: acc
+                | None ->
 
                 match positionalArgAttr with
                 | Some _ ->
+                    let getChoice (spec : ArgumentDefaultSpec option) : unit =
+                        match spec with
+                        | Some _ ->
+                            failwith
+                                "Positional Choice args cannot have default values. Remove [<ArgumentDefault*>] from the positional arg."
+                        | None -> ()
+
+                    let parser, accumulation, parseTy =
+                        createParseFunction<unit> getChoice ident attrs fieldType
+
                     match accumulation with
-                    | Accumulation.List ->
+                    | Accumulation.List (Accumulation.List _) ->
+                        failwith "A list of positional args cannot contain lists."
+                    | Accumulation.List Accumulation.Optional ->
+                        failwith "A list of positional args cannot contain optionals. What would that even mean?"
+                    | Accumulation.List (Accumulation.Choice ()) ->
                         {
                             FieldName = ident
                             Parser = parser
-                            TargetVariable = ident
-                            Accumulation = accumulation
+                            TargetVariable = Ident.create $"arg_%i{counter}"
+                            Accumulation = ChoicePositional.Choice
                             TargetType = parseTy
                             ArgForm = argify ident
                             Help = helpText
                         }
-                        |> ArgToParse.Positional
-                    | _ -> failwith $"Expected positional arg accumulation type to be List, but it was %O{fieldType}"
+                        |> fun t -> ParseTree.PositionalLeaf (t, Teq.refl)
+                    | Accumulation.List Accumulation.Required ->
+                        {
+                            FieldName = ident
+                            Parser = parser
+                            TargetVariable = Ident.create $"arg_%i{counter}"
+                            Accumulation = ChoicePositional.Normal
+                            TargetType = parseTy
+                            ArgForm = argify ident
+                            Help = helpText
+                        }
+                        |> fun t -> ParseTree.PositionalLeaf (t, Teq.refl)
+                    | Accumulation.Choice _
+                    | Accumulation.Optional
+                    | Accumulation.Required ->
+                        failwith $"Expected positional arg accumulation type to be List, but it was %O{fieldType}"
+                    |> ParseTreeCrate.make
                 | None ->
+                    let getChoice (spec : ArgumentDefaultSpec option) : ArgumentDefaultSpec =
+                        match spec with
+                        | None ->
+                            failwith
+                                "Non-positional Choice args must have an `[<ArgumentDefault*>]` attribute on them."
+                        | Some spec -> spec
+
+                    let parser, accumulation, parseTy =
+                        createParseFunction getChoice ident attrs fieldType
+
                     {
                         FieldName = ident
                         Parser = parser
-                        TargetVariable = ident
+                        TargetVariable = Ident.create $"arg_%i{counter}"
                         Accumulation = accumulation
                         TargetType = parseTy
                         ArgForm = argify ident
                         Help = helpText
                     }
-                    |> ArgToParse.NonPositional
+                    |> fun t -> ParseTree.NonPositionalLeaf (t, Teq.refl)
+                    |> ParseTreeCrate.make
+                |> fun tree -> counter + 1, (ident, tree) :: acc
             )
 
-        let positional, nonPositionals =
-            let mutable p = None
-            let n = ResizeArray ()
+        let tree =
+            contents
+            |> List.rev
+            |> ParseTree.branch (fun args ->
+                args
+                |> Map.toList
+                |> List.map (fun (ident, expr) -> SynLongIdent.create [ Ident.create ident ], expr)
+                |> AstHelper.instantiateRecord
+            )
 
-            for arg in args do
-                match arg with
-                | ArgToParse.Positional arg ->
-                    match p with
-                    | None -> p <- Some arg
-                    | Some existing ->
-                        failwith
-                            $"Multiple args were tagged with `Positional`: %s{existing.TargetVariable.idText}, %s{arg.TargetVariable.idText}"
-                | ArgToParse.NonPositional arg -> n.Add arg
-
-            p, List.ofSeq n
-
-        {
-            NonPositionals = nonPositionals
-            Positionals = positional
-        }
+        tree, counter
 
     /// let helpText : string = ...
     let private helpText
         (typeName : Ident)
-        (positional : ParseFunction option)
-        (args : ParseFunction list)
+        (positional : ParseFunctionPositional option)
+        (args : ParseFunctionNonPositional list)
         : SynBinding
         =
-        let toPrintable (prefix : string) (arg : ParseFunction) : SynExpr =
-            let ty = arg.TargetType |> SynType.toHumanReadableString
-
-            let helpText =
-                match arg.Help with
-                | None -> SynExpr.CreateConst ""
-                | Some helpText ->
-                    SynExpr.applyFunction (SynExpr.createIdent "sprintf") (SynExpr.CreateConst " : %s")
-                    |> SynExpr.applyTo (SynExpr.paren helpText)
-                    |> SynExpr.paren
-
-            let descriptor =
-                match arg.Accumulation with
+        let describeNonPositional (acc : Accumulation<ArgumentDefaultSpec>) : SynExpr =
+            match acc with
             | Accumulation.Required -> SynExpr.CreateConst ""
             | Accumulation.Optional -> SynExpr.CreateConst " (optional)"
             | Accumulation.Choice (ArgumentDefaultSpec.EnvironmentVariable var) ->
@@ -399,14 +598,28 @@ module internal ArgParserGenerator =
             | Accumulation.Choice (ArgumentDefaultSpec.FunctionCall var) ->
                 SynExpr.callMethod var.idText (SynExpr.createIdent' typeName)
                 |> SynExpr.pipeThroughFunction (
-                        SynExpr.applyFunction
-                            (SynExpr.createIdent "sprintf")
-                            (SynExpr.CreateConst " (default value: %O)")
+                    SynExpr.applyFunction (SynExpr.createIdent "sprintf") (SynExpr.CreateConst " (default value: %O)")
                 )
                 |> SynExpr.paren
-                | Accumulation.List -> SynExpr.CreateConst " (can be repeated)"
+            | Accumulation.List _ -> SynExpr.CreateConst " (can be repeated)"
 
-            let prefix = $"%s{arg.ArgForm}  %s{ty}%s{prefix}"
+        let describePositional _ =
+            SynExpr.CreateConst " (positional args) (can be repeated)"
+
+        let toPrintable (describe : 'a -> SynExpr) (arg : ParseFunction<'a>) : SynExpr =
+            let ty = arg.TargetType |> SynType.toHumanReadableString
+
+            let helpText =
+                match arg.Help with
+                | None -> SynExpr.CreateConst ""
+                | Some helpText ->
+                    SynExpr.applyFunction (SynExpr.createIdent "sprintf") (SynExpr.CreateConst " : %s")
+                    |> SynExpr.applyTo (SynExpr.paren helpText)
+                    |> SynExpr.paren
+
+            let descriptor = describe arg.Accumulation
+
+            let prefix = $"%s{arg.ArgForm}  %s{ty}"
 
             SynExpr.applyFunction (SynExpr.createIdent "sprintf") (SynExpr.CreateConst (prefix + "%s%s"))
             |> SynExpr.applyTo descriptor
@@ -414,11 +627,11 @@ module internal ArgParserGenerator =
             |> SynExpr.paren
 
         args
-        |> List.map (toPrintable "")
+        |> List.map (toPrintable describeNonPositional)
         |> fun l ->
             match positional with
             | None -> l
-            | Some pos -> l @ [ toPrintable " (positional args)" pos ]
+            | Some pos -> l @ [ toPrintable describePositional pos ]
         |> SynExpr.listLiteral
         |> SynExpr.pipeThroughFunction (
             SynExpr.applyFunction (SynExpr.createLongIdent [ "String" ; "concat" ]) (SynExpr.CreateConst @"\n")
@@ -429,9 +642,15 @@ module internal ArgParserGenerator =
     /// Returns a possible error.
     /// A parse failure might not be fatal (e.g. maybe the input was optionally of arity 0, and we failed to do
     /// the parse because in fact the key decided not to take this argument); in that case we return Error None.
-    let private processKeyValue (argParseErrors : Ident) (args : ParseFunction list) : SynBinding =
-        (SynExpr.applyFunction (SynExpr.createIdent "Error") (SynExpr.createIdent "None"), args)
-        ||> List.fold (fun finalBranch arg ->
+    let private processKeyValue
+        (argParseErrors : Ident)
+        (pos : ParseFunctionPositional option)
+        (args : ParseFunctionNonPositional list)
+        : SynBinding
+        =
+        let args =
+            args
+            |> List.map (fun arg ->
                 match arg.Accumulation with
                 | Accumulation.Required
                 | Accumulation.Choice _
@@ -475,23 +694,54 @@ module internal ArgParserGenerator =
                                 performAssignment)
                     ]
                     |> SynExpr.createMatch (SynExpr.createIdent' arg.TargetVariable)
-            | Accumulation.List ->
+                | Accumulation.List (Accumulation.List _)
+                | Accumulation.List Accumulation.Optional
+                | Accumulation.List (Accumulation.Choice _) ->
+                    failwith
+                        "WoofWare.Myriad invariant violated: expected a list to contain only a Required accumulation. Non-positional lists cannot be optional or Choice, nor can they themselves contain lists."
+                | Accumulation.List Accumulation.Required ->
                     [
                         SynExpr.createIdent "value"
+                        |> SynExpr.pipeThroughFunction arg.Parser
                         |> SynExpr.pipeThroughFunction (
                             SynExpr.createLongIdent' [ arg.TargetVariable ; Ident.create "Add" ]
                         )
-                    |> SynExpr.applyFunction arg.Parser
                         SynExpr.CreateConst () |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Ok")
                     ]
                     |> SynExpr.sequential
+                |> fun expr -> arg.ArgForm, expr
+            )
+
+        let posArg =
+            match pos with
+            | None -> []
+            | Some pos ->
+                [
+                    SynExpr.createIdent "value"
+                    |> SynExpr.pipeThroughFunction pos.Parser
+                    |> fun p ->
+                        match pos.Accumulation with
+                        | ChoicePositional.Choice -> p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
+                        | ChoicePositional.Normal -> p
+                    |> SynExpr.pipeThroughFunction (
+                        SynExpr.createLongIdent' [ pos.TargetVariable ; Ident.create "Add" ]
+                    )
+                    SynExpr.CreateConst () |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Ok")
+                ]
+                |> SynExpr.sequential
+                |> fun expr -> pos.ArgForm, expr
+                |> List.singleton
+
+        (SynExpr.applyFunction (SynExpr.createIdent "Error") (SynExpr.createIdent "None"), posArg @ args)
+        ||> List.fold (fun finalBranch (argForm, arg) ->
+            arg
             |> SynExpr.ifThenElse
                 (SynExpr.applyFunction
                     (SynExpr.createLongIdent [ "System" ; "String" ; "Equals" ])
                     (SynExpr.tuple
                         [
                             SynExpr.createIdent "key"
-                            SynExpr.CreateConst arg.ArgForm
+                            SynExpr.CreateConst argForm
                             SynExpr.createLongIdent [ "System" ; "StringComparison" ; "OrdinalIgnoreCase" ]
                         ]))
                 finalBranch
@@ -508,14 +758,14 @@ module internal ArgParserGenerator =
         |> SynBinding.withXmlDoc (
             [
                 " Processes the key-value pair, returning Error if no key was matched."
-                " If the key is an arg which can arity 1, but throws when consuming that arg, we return Error(<the message>)."
+                " If the key is an arg which can have arity 1, but throws when consuming that arg, we return Error(<the message>)."
                 " This can nevertheless be a successful parse, e.g. when the key may have arity 0."
             ]
             |> PreXmlDoc.create'
         )
 
     /// `let setFlagValue (key : string) : bool = ...`
-    let private setFlagValue (parseState : Ident) (argParseErrors : Ident) (flags : ParseFunction list) : SynBinding =
+    let private setFlagValue (argParseErrors : Ident) (flags : ParseFunction<'a> list) : SynBinding =
         (SynExpr.CreateConst false, flags)
         ||> List.fold (fun finalExpr flag ->
             let multipleErrorMessage =
@@ -564,11 +814,12 @@ module internal ArgParserGenerator =
     let private mainLoop
         (parseState : Ident)
         (errorAcc : Ident)
+        (leftoverArgAcc : ChoicePositional)
         (leftoverArgs : Ident)
         (leftoverArgParser : SynExpr)
         : SynBinding
         =
-        /// `go (AwaitingValue arg) args
+        /// `go (AwaitingValue arg) args`
         let recurseValue =
             SynExpr.createIdent "go"
             |> SynExpr.applyTo (
@@ -608,9 +859,14 @@ module internal ArgParserGenerator =
                 argStartsWithDashes
                 (SynExpr.sequential
                     [
-                        (SynExpr.createIdent "arg"
+                        SynExpr.createIdent "arg"
                         |> SynExpr.pipeThroughFunction leftoverArgParser
-                         |> SynExpr.pipeThroughFunction (SynExpr.createLongIdent' [ leftoverArgs ; Ident.create "Add" ]))
+                        |> fun p ->
+                            match leftoverArgAcc with
+                            | ChoicePositional.Normal -> p
+                            | ChoicePositional.Choice ->
+                                p |> SynExpr.pipeThroughFunction (SynExpr.createIdent "Choice1Of2")
+                        |> SynExpr.pipeThroughFunction (SynExpr.createLongIdent' [ leftoverArgs ; Ident.create "Add" ])
 
                         recurseKey
                     ])
@@ -775,6 +1031,16 @@ module internal ArgParserGenerator =
                             |> SynExpr.pipeThroughFunction (
                                 SynExpr.applyFunction (SynExpr.createLongIdent [ "Seq" ; "map" ]) leftoverArgParser
                             )
+                            |> fun p ->
+                                match leftoverArgAcc with
+                                | ChoicePositional.Normal -> p
+                                | ChoicePositional.Choice ->
+                                    p
+                                    |> SynExpr.pipeThroughFunction (
+                                        SynExpr.applyFunction
+                                            (SynExpr.createLongIdent [ "Seq" ; "map" ])
+                                            (SynExpr.createIdent "Choice2Of2")
+                                    )
                         ))
                         (SynExpr.createIdent' leftoverArgs))
                 SynMatchClause.create (SynPat.listCons (SynPat.named "arg") (SynPat.named "args")) argBody
@@ -786,18 +1052,24 @@ module internal ArgParserGenerator =
                 SynPat.named "state"
                 |> SynPat.annotateType (SynType.createLongIdent [ parseState ])
                 SynPat.named "args"
-                |> SynPat.annotateType (SynType.appPostfix "list" (SynType.string))
+                |> SynPat.annotateType (SynType.appPostfix "list" SynType.string)
             ]
 
         SynBinding.basic [ Ident.create "go" ] args body
         |> SynBinding.withRecursion true
 
     /// Takes a single argument, `args : string list`, and returns something of the type indicated by `recordType`.
-    let createRecordParse (parseState : Ident) (recordType : RecordType) : SynExpr =
-        let spec = toParseSpec recordType
+    let createRecordParse (parseState : Ident) (ambientRecords : RecordType list) (recordType : RecordType) : SynExpr =
+        let spec, _ = toParseSpec 0 ambientRecords recordType
         // For each argument (positional and non-positional), create an accumulator for it.
+        let nonPos, pos =
+            { new ParseTreeEval<_> with
+                member _.Eval tree = ParseTree.accumulators tree
+            }
+            |> spec.Apply
+
         let bindings =
-            spec.NonPositionals
+            nonPos
             |> List.map (fun pf ->
                 match pf.Accumulation with
                 | Accumulation.Required
@@ -807,7 +1079,12 @@ module internal ArgParserGenerator =
                     |> SynBinding.basic [ pf.TargetVariable ] []
                     |> SynBinding.withMutability true
                     |> SynBinding.withReturnAnnotation (SynType.appPostfix "option" pf.TargetType)
-                | Accumulation.List ->
+                | Accumulation.List (Accumulation.List _)
+                | Accumulation.List Accumulation.Optional
+                | Accumulation.List (Accumulation.Choice _) ->
+                    failwith
+                        "WoofWare.Myriad invariant violated: expected a list to contain only a Required accumulation. Non-positional lists cannot be optional or Choice, nor can they themselves contain lists."
+                | Accumulation.List Accumulation.Required ->
                     SynExpr.createIdent "ResizeArray"
                     |> SynExpr.applyTo (SynExpr.CreateConst ())
                     |> SynBinding.basic [ pf.TargetVariable ] []
@@ -816,12 +1093,16 @@ module internal ArgParserGenerator =
 
         let bindings, leftoverArgsName, leftoverArgsParser =
             let bindingName, leftoverArgsParser, leftoverArgsType =
-                match spec.Positionals with
+                match pos with
                 | None ->
                     Ident.create "parser_LeftoverArgs",
                     (SynExpr.createLambda "x" (SynExpr.createIdent "x")),
                     SynType.string
-                | Some pf -> pf.TargetVariable, pf.Parser, pf.TargetType
+                | Some pf ->
+                    match pf.Accumulation with
+                    | ChoicePositional.Choice ->
+                        pf.TargetVariable, pf.Parser, SynType.app "Choice" [ pf.TargetType ; pf.TargetType ]
+                    | ChoicePositional.Normal -> pf.TargetVariable, pf.Parser, pf.TargetType
 
             let bindings =
                 SynExpr.createIdent "ResizeArray"
@@ -839,7 +1120,7 @@ module internal ArgParserGenerator =
             |> SynExpr.applyTo (SynExpr.CreateConst ())
             |> SynBinding.basic [ argParseErrors ] []
 
-        let helpText = helpText recordType.Name spec.Positionals spec.NonPositionals
+        let helpText = helpText recordType.Name pos nonPos
 
         let bindings = errorCollection :: helpText :: bindings
 
@@ -849,7 +1130,7 @@ module internal ArgParserGenerator =
 
         // Determine whether any required arg is missing, and freeze args into immutable form.
         let freezeNonPositionalArgs =
-            spec.NonPositionals
+            nonPos
             |> List.map (fun pf ->
                 match pf.Accumulation with
                 | Accumulation.Choice spec ->
@@ -902,7 +1183,12 @@ module internal ArgParserGenerator =
                     |> SynBinding.basic [ pf.TargetVariable ] []
                 | Accumulation.Optional ->
                     SynBinding.basic [ pf.TargetVariable ] [] (SynExpr.createIdent' pf.TargetVariable)
-                | Accumulation.List ->
+                | Accumulation.List (Accumulation.List _)
+                | Accumulation.List Accumulation.Optional
+                | Accumulation.List (Accumulation.Choice _) ->
+                    failwith
+                        "WoofWare.Myriad invariant violated: expected a list to contain only a Required accumulation. Non-positional lists cannot be optional or Choice, nor can they themselves contain lists."
+                | Accumulation.List Accumulation.Required ->
                     SynBinding.basic
                         [ pf.TargetVariable ]
                         []
@@ -912,7 +1198,7 @@ module internal ArgParserGenerator =
                     let errorMessage =
                         SynExpr.createIdent "sprintf"
                         |> SynExpr.applyTo (SynExpr.CreateConst "Required argument '%s' received no value")
-                        |> SynExpr.applyTo (SynExpr.CreateConst (argify pf.TargetVariable))
+                        |> SynExpr.applyTo (SynExpr.CreateConst pf.ArgForm)
 
                     [
                         SynMatchClause.create
@@ -935,7 +1221,7 @@ module internal ArgParserGenerator =
             )
 
         let freezePositional =
-            match spec.Positionals with
+            match pos with
             | None ->
                 // Check if there are leftover args. If there are, throw.
                 let errorMessage =
@@ -969,20 +1255,12 @@ module internal ArgParserGenerator =
 
         let freezeArgs = freezePositional @ freezeNonPositionalArgs
 
-        let retPositional =
-            match spec.Positionals with
-            | None -> []
-            | Some pf ->
-                [
-                    SynLongIdent.createI pf.TargetVariable, SynExpr.createIdent' pf.TargetVariable
-                ]
-
         let retValue =
             let happyPath =
-                spec.NonPositionals
-                |> List.map (fun pf -> SynLongIdent.createI pf.TargetVariable, SynExpr.createIdent' pf.TargetVariable)
-                |> fun np -> retPositional @ np
-                |> AstHelper.instantiateRecord
+                { new ParseTreeEval<_> with
+                    member _.Eval tree = ParseTree.instantiate tree
+                }
+                |> spec.Apply
 
             let sadPath =
                 SynExpr.createIdent' argParseErrors
@@ -1001,13 +1279,18 @@ module internal ArgParserGenerator =
             SynExpr.ifThenElse areErrors sadPath happyPath
 
         let flags =
-            spec.NonPositionals
+            nonPos
             |> List.filter (fun pf ->
                 match pf.TargetType with
                 | PrimitiveType pt -> (pt |> List.map _.idText) = [ "System" ; "Boolean" ]
                 | _ -> false
             )
 
+        let leftoverArgAcc =
+            match pos with
+            | None -> ChoicePositional.Normal
+            | Some pos -> pos.Accumulation
+
         [
             SynExpr.createIdent "go"
             |> SynExpr.applyTo (SynExpr.createLongIdent' [ parseState ; Ident.create "AwaitingKey" ])
@@ -1019,9 +1302,9 @@ module internal ArgParserGenerator =
         |> SynExpr.createLet (
             bindings
             @ [
-                processKeyValue argParseErrors (Option.toList spec.Positionals @ spec.NonPositionals)
-                setFlagValue parseState argParseErrors flags
-                mainLoop parseState argParseErrors leftoverArgsName leftoverArgsParser
+                processKeyValue argParseErrors pos nonPos
+                setFlagValue argParseErrors flags
+                mainLoop parseState argParseErrors leftoverArgAcc leftoverArgsName leftoverArgsParser
             ]
         )
 
@@ -1029,10 +1312,13 @@ module internal ArgParserGenerator =
         (opens : SynOpenDeclTarget list)
         (ns : LongIdent)
         ((taggedType : SynTypeDefn, spec : ArgParserOutputSpec))
-        (_allUnionTypesTODO : SynTypeDefn list)
+        (allUnionTypes : SynTypeDefn list)
         (allRecordTypes : SynTypeDefn list)
         : SynModuleOrNamespace
         =
+        // The type for which we're generating args may refer to any of these records/unions.
+        let allRecordTypes = allRecordTypes |> List.map RecordType.OfRecord
+
         let taggedType = RecordType.OfRecord taggedType
 
         let modAttrs, modName =
@@ -1086,7 +1372,7 @@ module internal ArgParserGenerator =
                 |> SynPat.annotateType (SynType.appPostfix "list" SynType.string)
 
             let parsePrime =
-                createRecordParse parseStateIdent taggedType
+                createRecordParse parseStateIdent allRecordTypes taggedType
                 |> SynBinding.basic
                     [ Ident.create "parse'" ]
                     [
@@ -1146,16 +1432,19 @@ module internal ArgParserGenerator =
         let ast, _ =
             Ast.fromFilename context.InputFilename |> Async.RunSynchronously |> Array.head
 
-        let types = Ast.extractTypeDefn ast
+        let types =
+            Ast.extractTypeDefn ast
+            |> List.groupBy (fst >> List.map _.idText >> String.concat ".")
+            |> List.map (fun (_, v) -> fst (List.head v), List.collect snd v)
 
         let opens = AstHelper.extractOpens ast
 
         let namespaceAndTypes =
             types
-            |> List.choose (fun (ns, types) ->
+            |> List.collect (fun (ns, types) ->
                 let typeWithAttr =
                     types
-                    |> List.tryPick (fun ty ->
+                    |> List.choose (fun ty ->
                         match Ast.getAttribute<ArgParserAttribute> ty with
                         | None -> None
                         | Some attr ->
@@ -1175,8 +1464,8 @@ module internal ArgParserGenerator =
                             Some (ty, spec)
                     )
 
-                match typeWithAttr with
-                | Some taggedType ->
+                typeWithAttr
+                |> List.map (fun taggedType ->
                     let unions, records, others =
                         (([], [], []), types)
                         ||> List.fold (fun
@@ -1194,8 +1483,8 @@ module internal ArgParserGenerator =
                         failwith
                             $"Error: all types recursively defined together with an ArgParserGenerator type must be discriminated unions or records. %+A{others}"
 
-                    Some (ns, taggedType, unions, records)
-                | _ -> None
+                    (ns, taggedType, unions, records)
+                )
             )
 
         let modules =

WoofWare.Myriad.Plugins/Teq.fs

@@ -0,0 +1,18 @@
+namespace WoofWare.Myriad.Plugins
+
+// Extracted from https://github.com/G-Research/TypeEquality
+// which is Apache-2.0 licenced. See `TeqLicence.txt`.
+// We inline this code because Myriad doesn't seem to reliably load package references in the generator.
+// I have reformatted a little, and stripped out all the code I don't use.
+
+type internal Teq<'a, 'b> = private | Teq of ('a -> 'b) * ('b -> 'a)
+
+[<RequireQualifiedAccess>]
+module internal Teq =
+
+    let refl<'a> : Teq<'a, 'a> = Teq (id, id)
+    let cast (Teq (f, _)) a = f a
+
+    [<RequireQualifiedAccess>]
+    module Cong =
+        let believeMe<'a, 'b, 'a2, 'b2> (_ : Teq<'a, 'b>) : Teq<'a2, 'b2> = unbox <| (refl : Teq<'a2, 'a2>)

WoofWare.Myriad.Plugins/TeqLicence.txt

@@ -0,0 +1,201 @@
+Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
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+
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WoofWare.Myriad.Plugins/WoofWare.Myriad.Plugins.fsproj

@@ -25,6 +25,7 @@
 
   <ItemGroup>
     <Compile Include="List.fs"/>
+    <Compile Include="Teq.fs" />
     <Compile Include="Primitives.fs" />
     <Compile Include="SynExpr\SynAttributes.fs" />
     <Compile Include="SynExpr\PreXmlDoc.fs" />
@@ -56,6 +57,7 @@
     <Compile Include="HttpClientGenerator.fs"/>
     <Compile Include="CataGenerator.fs" />
     <Compile Include="ArgParserGenerator.fs" />
+    <None Include="TeqLicence.txt" />
     <EmbeddedResource Include="version.json"/>
     <EmbeddedResource Include="SurfaceBaseline.txt"/>
     <None Include="..\README.md">

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
     "version": "8.0.100",
-    "rollForward": "latestFeature"
+    "rollForward": "latestMajor"
   }
 }