implement import function

lib/ast.ml

@@ -51,6 +51,16 @@ module ReadSpreadsheet = struct
   ;;
 end
 
+module Import = struct
+  type t =
+    { var : Variable.T.t
+    ; from : Variable.T.t
+    }
+  [@@deriving sexp]
+
+  let to_string node = Printf.sprintf "Import %s from %s" node.var node.from
+end
+
 module Export = struct
   type t =
     | File of string
@@ -71,6 +81,7 @@ module Node = struct
     | ReadConstant of ReadConstant.t
     | ReadVariable of ReadVariable.t
     | ReadSpreadsheet of ReadSpreadsheet.t
+    | Import of Import.t
     | Export of Export.t
   [@@deriving sexp]
 
@@ -79,6 +90,7 @@ module Node = struct
     | ReadConstant n -> ReadConstant.to_string n
     | ReadVariable n -> ReadVariable.to_string n
     | ReadSpreadsheet n -> ReadSpreadsheet.to_string n
+    | Import n -> Import.to_string n
     | Export n -> Export.to_string n
   ;;
 end

lib/ast.mli

@@ -32,6 +32,17 @@ module ReadSpreadsheet : sig
   val to_string : t -> string
 end
 
+module Import : sig
+  type t =
+    { var : Variable.T.t
+    ; from : Variable.T.t
+    }
+
+  val t_of_sexp : Sexplib0.Sexp.t -> t
+  val sexp_of_t : t -> Sexplib0.Sexp.t
+  val to_string : t -> string
+end
+
 module Export : sig
   type t =
     | File of string
@@ -47,6 +58,7 @@ module Node : sig
     | ReadConstant of ReadConstant.t
     | ReadVariable of ReadVariable.t
     | ReadSpreadsheet of ReadSpreadsheet.t
+    | Import of Import.t
     | Export of Export.t
 
   val t_of_sexp : Sexplib0.Sexp.t -> t

lib/import.ml

@@ -0,0 +1,3 @@
+module T = struct
+  let to_string (var, from) = Printf.sprintf "import { %s } from \"%s\";" var from
+end

lib/import.mli

@@ -0,0 +1,3 @@
+module T : sig
+  val to_string : string * Variable.T.t -> string
+end

lib/interpreter.ml

@@ -3,6 +3,7 @@ module T = struct
     { variable_store : Literal.T.v Store.T.t
     ; spreadsheet_store : Spreadsheet.t Store.T.t
     ; interface_set : Variable.T.t Store.T.t
+    ; import_store : Variable.T.t Store.T.t
     }
 
   let interpret_read_constant state (node : Ast.ReadConstant.t) =
@@ -39,7 +40,15 @@ module T = struct
     | Csv p -> interpret_csv_spreadsheet state variable interface p
   ;;
 
+  let interpret_import state (node : Ast.Import.t) =
+    let target, from = node.var, node.from in
+    if not (Variable.T.is_valid target)
+    then failwith ("invalid import value name " ^ target);
+    Store.T.set_key state.import_store target from
+  ;;
+
   let interpret_export state (node : Ast.Export.t) =
+    let import_contents = Store.T.to_string state.import_store Import.T.to_string in
     let var_contents = Store.T.to_string state.variable_store Literal.T.to_string in
     let spreadsheet_contents =
       Store.T.to_string state.spreadsheet_store Spreadsheet.Writer.to_string
@@ -48,8 +57,10 @@ module T = struct
       Printf.sprintf
         {|
 %s
+%s
 %s
       |}
+        import_contents
         var_contents
         spreadsheet_contents
     in
@@ -69,6 +80,7 @@ module T = struct
     | Ast.Node.ReadConstant n -> interpret_read_constant state n
     | Ast.Node.ReadVariable n -> interpret_read_variable state n
     | Ast.Node.ReadSpreadsheet n -> interpret_read_spreadsheet state n
+    | Ast.Node.Import n -> interpret_import state n
     | Ast.Node.Export n ->
       interpret_export state n;
       reset_state state
@@ -78,6 +90,7 @@ module T = struct
     { variable_store = Store.T.create ()
     ; spreadsheet_store = Store.T.create ()
     ; interface_set = Store.T.create ()
+    ; import_store = Store.T.create ()
     }
   ;;
 

lib/interpreter.mli

@@ -3,6 +3,7 @@ module T : sig
     { variable_store : Literal.T.v Store.T.t
     ; spreadsheet_store : Spreadsheet.t Store.T.t
     ; interface_set : Variable.T.t Store.T.t
+    ; import_store : Variable.T.t Store.T.t
     }
 
   val interpret_node : state -> Ast.Node.t -> unit

test/expect_tests/cases/basic_program_test.sexp

@@ -1,4 +1,5 @@
 (
+	(Import ((var SomeEnum) (from some-file.ts)))
 	(ReadConstant ((var "thing") (value (String "ABCDEF"))))
 	(ReadConstant ((var "thing2") (value (Integer 123))))
 	(ReadVariable ((var "thing3") (value (Float 3.14))))

test/expect_tests/cases/fail_dupe_import.sexp

@@ -0,0 +1,5 @@
+(
+	(Import ((var SomeEnum) (from some-file.ts)))
+	(Import ((var SomeEnum) (from some-file-2.ts)))
+	(Export Stdout)
+)

test/expect_tests/cases/long_program_test.sexp

@@ -1,4 +1,7 @@
 (
+	(Import ((var SomeEnum) (from some-file.ts)))
+	(Import ((var SomeOtherEnum) (from some-other-file.ts)))
+	(Import ((var SomeOtherEnum2) (from some-other-file.ts)))
 	(ReadConstant ((var "thing") (value (String "ABCDEF"))))
 	(ReadConstant ((var "thing2") (value (Integer 123))))
 	(ReadSpreadsheet ((var "spreadsheet_123") (interface "SomeType") (path (Csv "./data/sample_spreadsheet.csv"))))

test/expect_tests/cases/medium_program_test.sexp

@@ -1,4 +1,6 @@
 (
+	(Import ((var SomeEnum) (from some-file.ts)))
+	(Import ((var SomeOtherEnum) (from some-other-file.ts)))
 	(ReadConstant ((var "dataset_name") (value (String "PEOPLE_NAMES"))))
 	(ReadSpreadsheet ((var "people_names") (interface "Person") (path (Csv "./data/sample_spreadsheet_medium.csv"))))
 	(Export Stdout)

test/expect_tests/end_to_end_program_tests.ml

@@ -6,6 +6,7 @@ let%expect_test "passes basic end to end test" =
   Entry.entry_point "basic_program_test.sexp";
   [%expect
     {|
+    import { SomeEnum } from "some-file.ts";
     export const thing2: number = 123;
     export const thing5: string = "a afsdafds afsdsa";
     export const thing: string = "ABCDEF";
@@ -31,6 +32,8 @@ let%expect_test "passes long end to end test" =
   Entry.entry_point "medium_program_test.sexp";
   [%expect
     {|
+    import { SomeEnum } from "some-file.ts";
+    import { SomeOtherEnum } from "some-other-file.ts";
     export const dataset_name: string = "PEOPLE_NAMES";
 
     export interface Person {
@@ -79,6 +82,9 @@ let%expect_test "passes long end to end test" =
   Entry.entry_point "long_program_test.sexp";
   [%expect
     {|
+    import { SomeEnum } from "some-file.ts";
+    import { SomeOtherEnum } from "some-other-file.ts";
+    import { SomeOtherEnum2 } from "some-other-file.ts";
     export const thing2: number = 123;
     export const thing: string = "ABCDEF";
 
@@ -260,3 +266,10 @@ let%expect_test "fails on duplicate interface name" =
     print_endline msg;
     [%expect {| variable SomeType already set |}]
 ;;
+
+let%expect_test "fails on duplicate imported modules" =
+  try Entry.entry_point "fail_dupe_import.sexp" with
+  | Failure msg ->
+    print_endline msg;
+    [%expect {| variable SomeEnum already set |}]
+;;

test/expect_tests/import_tests.ml

@@ -0,0 +1,66 @@
+open Conkeldurr
+
+let%expect_test "can import a basic file" =
+  let program =
+    {|
+  ((Import ((var abc) (from banana.ts)))
+  (Export Stdout))
+  |}
+  in
+  program |> Program.T.of_string |> Interpreter.T.interpret;
+  [%expect
+    {|
+  import { abc } from "banana.ts";
+  |}]
+;;
+
+let%expect_test "can import multiple files" =
+  let program =
+    {|
+  (
+  (Import ((var abc) (from banana/banana)))
+  (Import ((var def) (from abcdef)))
+  (Import ((var react) (from react)))
+  (Export Stdout))
+  |}
+  in
+  program |> Program.T.of_string |> Interpreter.T.interpret;
+  [%expect
+    {|
+    import { abc } from "banana/banana";
+    import { def } from "abcdef";
+    import { react } from "react";
+    |}]
+;;
+
+let%expect_test "can import multiple exports from one file" =
+  let program =
+    {|
+  (
+  (Import ((var abc) (from banana/banana)))
+  (Import ((var def) (from banana/banana)))
+  (Export Stdout))
+  |}
+  in
+  program |> Program.T.of_string |> Interpreter.T.interpret;
+  [%expect
+    {|
+    import { abc } from "banana/banana";
+    import { def } from "banana/banana";
+    |}]
+;;
+
+let%expect_test "fails on importing identical exports" =
+  let program =
+    {|
+  (
+  (Import ((var abc) (from banana/banana)))
+  (Import ((var abc) (from abcdef)))
+  (Export Stdout))
+  |}
+  in
+  try program |> Program.T.of_string |> Interpreter.T.interpret with
+  | Failure msg ->
+    print_endline msg;
+    [%expect {| variable abc already set |}]
+;;