Add flag to disable reflection

Author: alfonsogarciacaro

src/Fable.AST/Plugins.fs

@@ -26,6 +26,7 @@ type CompilerOptions =
         Verbosity: Verbosity
         FileExtension: string
         TriggeredByDependency: bool
+        NoReflection: bool
     }
 
 type PluginHelper =

src/Fable.Cli/Entry.fs

@@ -6,9 +6,11 @@ open Fable
 
 type CliArgs(args: string list) =
     let argsMap =
-        let even = List.length args % 2 = 0
-        // If arguments are odd, assume last has true value in case it's a flag
-        let args = if even then args else args @ ["true"]
+        let args =
+            // Assume last arg has true value in case it's a flag
+            match List.tryLast args with
+            | Some key when key.StartsWith("-") -> args @ ["true"]
+            | _ -> args
         (Map.empty, List.windowed 2 args) ||> List.fold (fun map pair ->
             match pair with
             | [key; value] when key.StartsWith("-") ->
@@ -73,6 +75,7 @@ let knownCliArgs() = [
 
   // Hidden args
   ["--precompiledLib"], []
+  ["--noReflection"], []
   ["--typescript"], []
   ["--trimRootModule"], []
   ["--fableLib"], []
@@ -231,6 +234,7 @@ type Runner =
                                    define = define,
                                    debugMode = (configuration = "Debug"),
                                    optimizeFSharpAst = args.FlagEnabled "--optimize",
+                                   noReflection = args.FlagEnabled "--noReflection",
                                    verbosity = verbosity)
 
     let cliArgs =

src/Fable.Cli/Main.fs

@@ -484,12 +484,15 @@ and FableCompiler(projCracked: ProjectCracked, fableProj: Project, checker: Inte
         agent.PostAndAsyncReply(GetFableProject)
 
     member _.StartCompilation(sourceFiles, filesToCompile, pathResolver, isSilent, isTriggeredByDependency) = async {
-        if not isSilent then
-            Log.always "Started Fable compilation..."
-        let! results, ms = Performance.measureAsync <| fun () ->
-            agent.PostAndAsyncReply(fun channel -> StartCompilation(sourceFiles, filesToCompile, pathResolver, isSilent, isTriggeredByDependency, channel))
-        Log.always $"Fable compilation finished in %i{ms}ms{Log.newLine}"
-        return results
+        if Array.isEmpty filesToCompile then
+            return [||], []
+        else
+            if not isSilent then
+                Log.always "Started Fable compilation..."
+            let! results, ms = Performance.measureAsync <| fun () ->
+                agent.PostAndAsyncReply(fun channel -> StartCompilation(sourceFiles, filesToCompile, pathResolver, isSilent, isTriggeredByDependency, channel))
+            Log.always $"Fable compilation finished in %i{ms}ms{Log.newLine}"
+            return results
     }
 
     static member CheckIfCompilationIsFinished(state: FableCompilerState) =

src/Fable.Transforms/Fable2Babel.fs

@@ -951,7 +951,9 @@ module Util =
         | Fable.BaseValue(None,_) -> Super(None)
         | Fable.BaseValue(Some boundIdent,_) -> identAsExpr boundIdent
         | Fable.ThisValue _ -> Expression.thisExpression()
-        | Fable.TypeInfo t -> transformTypeInfo com ctx r (Some Map.empty) t
+        | Fable.TypeInfo t ->
+            if com.Options.NoReflection then addErrorAndReturnNull com r "Reflection is disabled"
+            else transformTypeInfo com ctx r (Some Map.empty) t
         | Fable.Null _t ->
             // if com.Options.typescript
             //     let ta = typeAnnotation com ctx t |> TypeAnnotation |> Some
@@ -1971,20 +1973,23 @@ module Util =
 
     let declareType (com: IBabelCompiler) ctx (ent: Fable.Entity) entName (consArgs: Pattern[]) (consBody: BlockStatement) baseExpr classMembers: ModuleDeclaration list =
         let typeDeclaration = declareClassType com ctx ent entName consArgs consBody baseExpr classMembers
-        let reflectionDeclaration =
-            let ta =
-                if com.Options.Language = TypeScript then
-                    makeImportTypeAnnotation com ctx [] "Reflection" "TypeInfo"
-                    |> TypeAnnotation |> Some
-                else None
-            let genArgs = Array.init (ent.GenericParameters.Length) (fun i -> "gen" + string i |> makeIdent)
-            let generics = genArgs |> Array.map identAsExpr
-            let body = transformReflectionInfo com ctx None ent generics
-            let args = genArgs |> Array.map (fun x -> Pattern.identifier(x.Name, ?typeAnnotation=ta))
-            let returnType = ta
-            makeFunctionExpression None (args, body, returnType, None)
-            |> declareModuleMember ent.IsPublic (entName + Naming.reflectionSuffix) false
-        [typeDeclaration; reflectionDeclaration]
+        if com.Options.NoReflection then
+            [typeDeclaration]
+        else
+            let reflectionDeclaration =
+                let ta =
+                    if com.Options.Language = TypeScript then
+                        makeImportTypeAnnotation com ctx [] "Reflection" "TypeInfo"
+                        |> TypeAnnotation |> Some
+                    else None
+                let genArgs = Array.init (ent.GenericParameters.Length) (fun i -> "gen" + string i |> makeIdent)
+                let generics = genArgs |> Array.map identAsExpr
+                let body = transformReflectionInfo com ctx None ent generics
+                let args = genArgs |> Array.map (fun x -> Pattern.identifier(x.Name, ?typeAnnotation=ta))
+                let returnType = ta
+                makeFunctionExpression None (args, body, returnType, None)
+                |> declareModuleMember ent.IsPublic (entName + Naming.reflectionSuffix) false
+            [typeDeclaration; reflectionDeclaration]
 
     let transformModuleFunction (com: IBabelCompiler) ctx (info: Fable.MemberInfo) (membName: string) args body =
         let args, body, returnType, typeParamDecl =

src/Fable.Transforms/Global/Compiler.fs

@@ -12,7 +12,8 @@ type CompilerOptionsHelper =
                        ?optimizeFSharpAst,
                        ?verbosity,
                        ?fileExtension,
-                       ?clampByteArrays) =
+                       ?clampByteArrays,
+                       ?noReflection) =
         {
             CompilerOptions.Define = defaultArg define []
             DebugMode = defaultArg debugMode true
@@ -23,6 +24,7 @@ type CompilerOptionsHelper =
             Verbosity = defaultArg verbosity Verbosity.Normal
             FileExtension = defaultArg fileExtension CompilerOptionsHelper.DefaultExtension
             ClampByteArrays = defaultArg clampByteArrays false
+            NoReflection = defaultArg noReflection false
             TriggeredByDependency = false
         }