Deal with unit type in generated mock (#124)

ConsumePlugin/GeneratedMock.fs

@@ -26,7 +26,7 @@ type internal PublicTypeMock =
 
     interface IPublicType with
         member this.Mem1 (arg_0_0, arg_0_1) = this.Mem1 (arg_0_0, arg_0_1)
-        member this.Mem2 (arg_0_0) = this.Mem2 (arg_0_0)
+        member this.Mem2 arg_0_0 = this.Mem2 (arg_0_0)
         member this.Mem3 (arg_0_0, arg_0_1) = this.Mem3 (arg_0_0, arg_0_1)
 namespace SomeNamespace
 
@@ -51,7 +51,7 @@ type public PublicTypeInternalFalseMock =
 
     interface IPublicTypeInternalFalse with
         member this.Mem1 (arg_0_0, arg_0_1) = this.Mem1 (arg_0_0, arg_0_1)
-        member this.Mem2 (arg_0_0) = this.Mem2 (arg_0_0)
+        member this.Mem2 arg_0_0 = this.Mem2 (arg_0_0)
         member this.Mem3 (arg_0_0, arg_0_1) = this.Mem3 (arg_0_0, arg_0_1)
 namespace SomeNamespace
 
@@ -74,7 +74,7 @@ type internal InternalTypeMock =
 
     interface InternalType with
         member this.Mem1 (arg_0_0, arg_0_1) = this.Mem1 (arg_0_0, arg_0_1)
-        member this.Mem2 (arg_0_0) = this.Mem2 (arg_0_0)
+        member this.Mem2 arg_0_0 = this.Mem2 (arg_0_0)
 namespace SomeNamespace
 
 open System
@@ -96,7 +96,7 @@ type private PrivateTypeMock =
 
     interface PrivateType with
         member this.Mem1 (arg_0_0, arg_0_1) = this.Mem1 (arg_0_0, arg_0_1)
-        member this.Mem2 (arg_0_0) = this.Mem2 (arg_0_0)
+        member this.Mem2 arg_0_0 = this.Mem2 (arg_0_0)
 namespace SomeNamespace
 
 open System
@@ -118,7 +118,7 @@ type private PrivateTypeInternalFalseMock =
 
     interface PrivateTypeInternalFalse with
         member this.Mem1 (arg_0_0, arg_0_1) = this.Mem1 (arg_0_0, arg_0_1)
-        member this.Mem2 (arg_0_0) = this.Mem2 (arg_0_0)
+        member this.Mem2 arg_0_0 = this.Mem2 (arg_0_0)
 namespace SomeNamespace
 
 open System
@@ -137,7 +137,7 @@ type internal VeryPublicTypeMock<'a, 'b> =
         }
 
     interface VeryPublicType<'a, 'b> with
-        member this.Mem1 (arg_0_0) = this.Mem1 (arg_0_0)
+        member this.Mem1 arg_0_0 = this.Mem1 (arg_0_0)
 namespace SomeNamespace
 
 open System
@@ -166,9 +166,9 @@ type internal CurriedMock<'a> =
         }
 
     interface Curried<'a> with
-        member this.Mem1 (arg_0_0) (arg_1_0) = this.Mem1 (arg_0_0) (arg_1_0)
-        member this.Mem2 (arg_0_0, arg_0_1) (arg_1_0) = this.Mem2 (arg_0_0, arg_0_1) (arg_1_0)
-        member this.Mem3 ((arg_0_0, arg_0_1)) (arg_1_0) = this.Mem3 (arg_0_0, arg_0_1) (arg_1_0)
+        member this.Mem1 arg_0_0 arg_1_0 = this.Mem1 (arg_0_0) (arg_1_0)
+        member this.Mem2 (arg_0_0, arg_0_1) arg_1_0 = this.Mem2 (arg_0_0, arg_0_1) (arg_1_0)
+        member this.Mem3 ((arg_0_0, arg_0_1)) arg_1_0 = this.Mem3 (arg_0_0, arg_0_1) (arg_1_0)
 
         member this.Mem4 ((arg_0_0, arg_0_1)) ((arg_1_0, arg_1_1)) =
             this.Mem4 (arg_0_0, arg_0_1) (arg_1_0, arg_1_1)
@@ -189,6 +189,7 @@ type internal TypeWithInterfaceMock =
         /// Implementation of IDisposable.Dispose
         Dispose : unit -> unit
         Mem1 : string option -> string[] Async
+        Mem2 : unit -> string[] Async
     }
 
     /// An implementation where every method throws.
@@ -196,10 +197,12 @@ type internal TypeWithInterfaceMock =
         {
             Dispose = (fun _ -> ())
             Mem1 = (fun x -> raise (System.NotImplementedException "Unimplemented mock function"))
+            Mem2 = (fun x -> raise (System.NotImplementedException "Unimplemented mock function"))
         }
 
     interface TypeWithInterface with
-        member this.Mem1 (arg_0_0) = this.Mem1 (arg_0_0)
+        member this.Mem1 arg_0_0 = this.Mem1 (arg_0_0)
+        member this.Mem2 () = this.Mem2 (())
 
     interface System.IDisposable with
         member this.Dispose () : unit = this.Dispose ()

ConsumePlugin/MockExample.fs

@@ -47,3 +47,4 @@ type Curried<'a> =
 type TypeWithInterface =
     inherit IDisposable
     abstract Mem1 : string option -> string[] Async
+    abstract Mem2 : unit -> string[] Async

WoofWare.Myriad.Plugins/AstHelper.fs

@@ -1,5 +1,6 @@
 namespace WoofWare.Myriad.Plugins
 
+open System.IO
 open Fantomas.FCS.Syntax
 open Fantomas.FCS.SyntaxTrivia
 open Fantomas.FCS.Text.Range
@@ -132,6 +133,11 @@ module internal AstHelper =
         // TODO: consider Microsoft.FSharp.Option or whatever it is
         | _ -> false
 
+    let isUnitIdent (ident : SynLongIdent) : bool =
+        match ident.LongIdent with
+        | [ i ] when System.String.Equals (i.idText, "unit", System.StringComparison.OrdinalIgnoreCase) -> true
+        | _ -> false
+
     let isListIdent (ident : SynLongIdent) : bool =
         match ident.LongIdent with
         | [ i ] when System.String.Equals (i.idText, "list", System.StringComparison.OrdinalIgnoreCase) -> true
@@ -502,6 +508,11 @@ module internal SynTypePatterns =
             Some innerType
         | _ -> None
 
+    let (|UnitType|_|) (fieldType : SynType) : unit option =
+        match fieldType with
+        | SynType.LongIdent ident when AstHelper.isUnitIdent ident -> Some ()
+        | _ -> None
+
     let (|ListType|_|) (fieldType : SynType) =
         match fieldType with
         | SynType.App (SynType.LongIdent ident, _, [ innerType ], _, _, _, _) when AstHelper.isListIdent ident ->

WoofWare.Myriad.Plugins/InterfaceMockGenerator.fs

@@ -194,7 +194,9 @@ module internal InterfaceMockGenerator =
                                                 |> List.mapi (fun i arg ->
                                                     arg.Args
                                                     |> List.mapi (fun j arg ->
-                                                        SynArgInfo.CreateIdString $"arg_%i{i}_%i{j}"
+                                                        match arg.Type with
+                                                        | UnitType -> SynArgInfo.SynArgInfo ([], false, None)
+                                                        | _ -> SynArgInfo.CreateIdString $"arg_%i{i}_%i{j}"
                                                     )
                                                 )
                                         ],
@@ -209,10 +211,18 @@ module internal InterfaceMockGenerator =
                         |> List.mapi (fun i tupledArgs ->
                             let args =
                                 tupledArgs.Args
-                                |> List.mapi (fun j _ -> SynPat.CreateNamed (Ident.Create $"arg_%i{i}_%i{j}"))
+                                |> List.mapi (fun j ty ->
+                                    match ty.Type with
+                                    | UnitType -> SynPat.Const (SynConst.Unit, range0)
+                                    | _ -> SynPat.CreateNamed (Ident.Create $"arg_%i{i}_%i{j}")
+                                )
 
-                            SynPat.Tuple (false, args, List.replicate (args.Length - 1) range0, range0)
-                            |> SynPat.CreateParen
+                            match args with
+                            | [] -> failwith "somehow got no args at all"
+                            | [ arg ] -> arg
+                            | args ->
+                                SynPat.Tuple (false, args, List.replicate (args.Length - 1) range0, range0)
+                                |> SynPat.CreateParen
                             |> fun i -> if tupledArgs.HasParen then SynPat.Paren (i, range0) else i
                         )
 
@@ -231,7 +241,11 @@ module internal InterfaceMockGenerator =
                             memberInfo.Args
                             |> List.mapi (fun i args ->
                                 args.Args
-                                |> List.mapi (fun j args -> SynExpr.CreateIdentString $"arg_%i{i}_%i{j}")
+                                |> List.mapi (fun j arg ->
+                                    match arg.Type with
+                                    | UnitType -> SynExpr.CreateConst SynConst.Unit
+                                    | _ -> SynExpr.CreateIdentString $"arg_%i{i}_%i{j}"
+                                )
                                 |> SynExpr.CreateParenedTuple
                             )