[flow][refactor] Move assert_export_is_type from ImportExport to …

…`TypeAssertions` module

Summary:
Instead of leaving the only one behind, let's re-organize.

Changelog: [internal]

Reviewed By: gkz

Differential Revision: D69140885

fbshipit-source-id: bc5c9941a12b4797fcc0bd01f9c6c8c50421ace1

src/typing/statement.ml

@@ -944,7 +944,7 @@ module Make
     let export_ref loc local_name =
       let t = Type_env.var_ref ~lookup_mode cx local_name loc in
       match export_kind with
-      | Ast.Statement.ExportType -> (None, Import_export.assert_export_is_type cx local_name t)
+      | Ast.Statement.ExportType -> (None, TypeAssertions.assert_export_is_type cx local_name t)
       | Ast.Statement.ExportValue -> (None, t)
     in
     (* [declare] export [type] {foo [as bar]} from 'module' *)

src/typing/type_operation_utils.ml

@@ -89,19 +89,6 @@ module DistributeUnionIntersection = struct
            )
 end
 
-module Import_export = struct
-  let assert_export_is_type cx name t =
-    let reason = TypeUtil.reason_of_t t in
-    Tvar_resolver.mk_tvar_and_fully_resolve_where cx reason (fun tout ->
-        let t =
-          t
-          |> Flow.singleton_concretize_type_for_imports_exports cx reason
-          |> Flow_js_utils.AssertExportIsTypeTKit.on_concrete_type cx name
-        in
-        Flow.flow_t cx (t, tout)
-    )
-end
-
 module Operators = struct
   let arith cx reason kind t1 t2 =
     Tvar_resolver.mk_tvar_and_fully_resolve_where cx reason (fun tout ->
@@ -536,6 +523,17 @@ module TypeAssertions = struct
       | l -> add_output cx (Error_message.EBinaryInRHS (reason_of_t l))
     )
 
+  let assert_export_is_type cx name t =
+    let reason = TypeUtil.reason_of_t t in
+    Tvar_resolver.mk_tvar_and_fully_resolve_where cx reason (fun tout ->
+        let t =
+          t
+          |> Flow.singleton_concretize_type_for_imports_exports cx reason
+          |> Flow_js_utils.AssertExportIsTypeTKit.on_concrete_type cx name
+        in
+        Flow.flow_t cx (t, tout)
+    )
+
   let assert_for_in_rhs cx t =
     DistributeUnionIntersection.distribute
       cx

src/typing/type_operation_utils.mli

@@ -31,10 +31,6 @@ module DistributeUnionIntersection : sig
     unit
 end
 
-module Import_export : sig
-  val assert_export_is_type : Context.t -> Reason.name -> Type.t -> Type.t
-end
-
 module Operators : sig
   val arith : Context.t -> reason -> Type.ArithKind.t -> Type.t -> Type.t -> Type.t
 
@@ -65,6 +61,8 @@ module TypeAssertions : sig
 
   val assert_binary_in_rhs : Context.t -> Type.t -> unit
 
+  val assert_export_is_type : Context.t -> Reason.name -> Type.t -> Type.t
+
   val assert_for_in_rhs : Context.t -> Type.t -> unit
 
   val assert_non_component_like_base :