merge rule evaluation (#278)

lib/app/comby.ml

@@ -25,11 +25,12 @@ module Rule = struct
   type t = Rule.t
   type result = Rule.result
 
-  let sat = Rule.Alpha.sat
-  let result_env = Rule.Alpha.result_env
+  let sat = Rule.sat
+  let result_env = Rule.result_env
   let create = Rule.create
-  let apply = Rule.Alpha.apply
+  let apply = Rule.apply
 end
+
 type rule = Rule.t
 
 module Replacement = Replacement

lib/app/configuration/command_configuration.ml

@@ -223,6 +223,7 @@ type user_input_options =
   ; override_matcher : string option
   ; regex_pattern : bool
   ; ripgrep_args : string option
+  ; omega : bool
   }
 
 type number_of_workers = int
@@ -239,7 +240,6 @@ type run_options =
   ; dump_statistics : bool
   ; substitute_in_place : bool
   ; disable_substring_matching : bool
-  ; omega : bool
   ; fast_offset_conversion : bool
   ; match_newline_toplevel : bool
   ; bound_count : int option
@@ -717,8 +717,9 @@ let create
          ; override_matcher
          ; regex_pattern
          ; ripgrep_args
+         ; omega
          }
-     ; run_options = ({ omega; _ } as run_options)
+     ; run_options
      ; output_options =
          ({ overwrite_file_in_place
           ; color

lib/app/configuration/command_configuration.mli

@@ -56,6 +56,7 @@ type user_input_options =
   ; override_matcher : string option
   ; regex_pattern : bool
   ; ripgrep_args : string option
+  ; omega : bool
   }
 
 type compute_mode =
@@ -70,7 +71,6 @@ type run_options =
   ; dump_statistics : bool
   ; substitute_in_place : bool
   ; disable_substring_matching : bool
-  ; omega : bool
   ; fast_offset_conversion : bool
   ; match_newline_toplevel : bool
   ; bound_count : int option

lib/app/pipeline/pipeline.ml

@@ -27,25 +27,18 @@ let infer_equality_constraints environment =
       else
         acc)
 
-let apply_rule ?(substitute_in_place = true) ?metasyntax matcher omega rule matches =
+let apply_rule ?(substitute_in_place = true) ?metasyntax matcher rule matches =
   let open Option in
   List.filter_map matches ~f:(fun ({ environment; _ } as matched) ->
       let rule = rule @ infer_equality_constraints environment in
-      let apply =
-        if omega then
-          Rule.Omega.apply ?metasyntax
-        else
-          Rule.Alpha.apply ?metasyntax
-      in
       let fresh () = Uuid_unix.(Fn.compose Uuid.to_string create ()) in
-      let sat, env = apply ~fresh ~substitute_in_place ~matcher rule environment in
+      let sat, env = Rule.apply ?metasyntax ~fresh ~substitute_in_place ~matcher rule environment in
       (if sat then env else None)
       >>| fun environment -> { matched with environment })
 
 let timed_run
     (module Matcher : Matchers.Matcher.S)
     ?(fast_offset_conversion = false)
-    ?(omega = false)
     ?substitute_in_place
     ?metasyntax
     ~configuration
@@ -56,9 +49,9 @@ let timed_run
    | Some template -> Matcher.set_rewrite_template template;
    | None -> ());
   let rule = Option.value rule ~default:[Ast.True] in
-  let options = if omega then Rule.Omega.options rule else Rule.Alpha.options rule in
+  let options = Rule.options rule in
   let matches = Matcher.all ~nested:options.nested ~configuration ~template ~source () in
-  let matches = apply_rule ?substitute_in_place ?metasyntax (module Matcher) omega rule matches in
+  let matches = apply_rule ?substitute_in_place ?metasyntax (module Matcher) rule matches in
   List.map matches ~f:(Match.convert_offset ~fast:fast_offset_conversion ~source)
 
 type output =
@@ -80,7 +73,6 @@ let log_to_file path =
 
 let process_single_source
     matcher
-    ?(omega = false)
     ?(fast_offset_conversion = false)
     ?(substitute_in_place = false)
     ?(verbose = false)
@@ -105,7 +97,6 @@ let process_single_source
             matcher
             ?metasyntax
             ~substitute_in_place
-            ~omega
             ~fast_offset_conversion
             ~configuration
             ~specification
@@ -237,7 +228,6 @@ let run_batch ~f:per_unit sources compute_mode bound_count =
 let run_interactive
     specifications
     matcher
-    omega
     fast_offset_conversion
     substitute_in_place
     match_configuration
@@ -252,7 +242,6 @@ let run_interactive
       (fun (input : single_source) specification ->
          process_single_source
            matcher
-           ~omega
            ~fast_offset_conversion
            ~substitute_in_place
            ~verbose
@@ -287,7 +276,6 @@ let run
         ; dump_statistics
         ; substitute_in_place
         ; disable_substring_matching
-        ; omega
         ; fast_offset_conversion
         ; match_newline_toplevel
         ; bound_count
@@ -321,7 +309,6 @@ let run
       (fun input specification ->
          process_single_source
            matcher
-           ~omega
            ~fast_offset_conversion
            ~substitute_in_place
            ~verbose
@@ -345,7 +332,6 @@ let run
       run_interactive
         specifications
         matcher
-        omega
         fast_offset_conversion
         substitute_in_place
         match_configuration
@@ -368,7 +354,6 @@ let execute
     specification =
   process_single_source
     matcher
-    ~omega:false
     ~fast_offset_conversion:false
     ?substitute_in_place
     ~verbose:false

lib/app/pipeline/pipeline.mli

@@ -8,7 +8,6 @@ type output =
 
 val process_single_source
   :  (module Matchers.Matcher.S)
-  -> ?omega:bool
   -> ?fast_offset_conversion:bool
   -> ?substitute_in_place:bool
   -> ?verbose:bool

lib/kernel/comby_kernel.ml

@@ -25,10 +25,10 @@ module Rule = struct
   type t = Rule.t
   type result = Rule.result
 
-  let sat = Rule.Alpha.sat
-  let result_env = Rule.Alpha.result_env
+  let sat = Rule.sat
+  let result_env = Rule.result_env
   let create = Rule.create
-  let apply = Rule.Alpha.apply
+  let apply = Rule.apply
 end
 
 type rule = Rule.t

lib/kernel/language/omega_rule.ml

@@ -1,172 +0,0 @@
-open Core_kernel
-open Angstrom
-
-open Ast
-
-open Match
-open Rewriter
-
-
-module Configuration = Matchers.Configuration
-
-type t = Ast.t
-
-type result = bool * environment option
-
-type options = Options.t
-
-let options = Options.of_rule
-
-let (|>>) p f =
-  p >>= fun x -> return (f x)
-
-let sat = fst
-
-let result_env = snd
-
-let match_configuration_of_syntax template =
-  (* decide match configuration based on whether there are holes *)
-  let antecedent_contains_hole_syntax case =
-    String.is_substring case ~substring:Syntax.variable_left_delimiter
-  in
-  if antecedent_contains_hole_syntax template then
-    Configuration.create ~match_kind:Fuzzy ()
-  else
-    Configuration.create ~match_kind:Exact ()
-
-let merge_match_environments matches environment' =
-  List.map matches ~f:(fun { environment; _ } ->
-      Environment.merge environment environment')
-
-type rewrite_context =
-  { variable : string }
-
-let counter =
-  let uuid_for_id_counter = ref 0 in
-  fun () ->
-    uuid_for_id_counter := !uuid_for_id_counter + 1;
-    Format.sprintf "gu3ssme_%012d" !uuid_for_id_counter
-
-let rec apply
-    ?(matcher = (module Matchers.Omega.Generic : Matchers.Matcher.S))
-    ?(substitute_in_place = true)
-    ?(fresh = counter)
-    ?metasyntax
-    predicates
-    env =
-  let open Option in
-  let (module Matcher) = matcher in
-
-  let equal_in_environment var value env =
-    match Environment.lookup env var with
-    | None -> false, Some env
-    | Some var_value -> String.equal var_value value, Some env
-  in
-  (* accepts only one expression *)
-  let rec rule_match ?(rewrite_context : rewrite_context option) env =
-    function
-    | True -> true, Some env
-    | False -> false, Some env
-    | Option _ -> true, Some env
-    | Equal (Variable var, String value)
-    | Equal (String value, Variable var) ->
-      equal_in_environment var value env
-    | Equal (String left, String right) ->
-      String.equal left right, Some env
-    | Equal (Variable left, Variable right) ->
-      let result =
-        Environment.lookup env left >>= fun left ->
-        Environment.lookup env right >>= fun right ->
-        return (String.equal left right)
-      in
-      Option.value result ~default:false, Some env
-    | Not_equal (left, right) ->
-      let sat, env = rule_match env (Equal (left, right)) in
-      not sat, env
-    | Match (Variable variable, cases) ->
-      let result =
-        Environment.lookup env variable >>= fun source ->
-        List.find_map cases ~f:(fun (template, case_expression) ->
-            match template with
-            | String template ->
-              begin
-                let configuration = match_configuration_of_syntax template in
-                Matcher.all ~configuration ~template ~source () |> function
-                | [] -> None
-                | matches ->
-                  (* merge environments. overwrite behavior is undefined *)
-                  let fold_matches (sat, out) { environment; _ } =
-                    let fold_cases (sat, out) predicate =
-                      if sat then
-                        let env' = Environment.merge env environment in
-                        rule_match ?rewrite_context env' predicate
-                      else
-                        (sat, out)
-                    in
-                    List.fold case_expression ~init:(sat, out) ~f:fold_cases
-                  in
-                  List.fold matches ~init:(true, None) ~f:fold_matches
-                  |> Option.some
-              end
-            | Variable _ ->
-              failwith "| :[hole] is invalid. Maybe you meant to put quotes")
-      in
-      Option.value_map result ~f:ident ~default:(false, Some env)
-    | Match (String template, cases) ->
-      let source, _ = Rewriter.Rewrite_template.substitute ?metasyntax template env in
-      let fresh_var = fresh () in
-      let env = Environment.add env fresh_var source in
-      rule_match env (Match (Variable fresh_var, cases))
-    | RewriteTemplate rewrite_template ->
-      begin
-        match rewrite_context with
-        | None -> false, None
-        | Some { variable; _ } ->
-          (* FIXME(RVT) assumes only contextual rewrite for now. *)
-          let env =
-            Rewrite_template.substitute ?metasyntax rewrite_template env
-            |> fst
-            |> fun replacement' ->
-            Environment.update env variable replacement'
-            |> Option.some
-          in
-          true, env
-      end
-    | Rewrite (Variable variable, (match_template, rewrite_expression)) ->
-      begin match rewrite_expression with
-        | RewriteTemplate rewrite_template ->
-          let template =
-            match match_template with
-            | Variable _ -> failwith "Invalid syntax in rewrite LHS"
-            | String template -> template
-          in
-          let result =
-            Environment.lookup env variable >>= fun source ->
-            let configuration = Configuration.create ~match_kind:Fuzzy () in
-            let matches = Matcher.all ~configuration ~template ~source () in
-            let source = if substitute_in_place then Some source else None in
-            let result = Rewrite.all ?metasyntax ?source ~rewrite_template matches in
-            match result with
-            | Some { rewritten_source; _ } ->
-              (* substitute for variables that are in the outside scope *)
-              let rewritten_source, _ = Rewrite_template.substitute rewritten_source env in
-              let env = Environment.update env variable rewritten_source in
-              return (true, Some env)
-            | None ->
-              return (true, Some env)
-          in
-          Option.value_map result ~f:ident ~default:(false, Some env)
-        | _ -> failwith "Not implemented yet"
-      end
-    | Rewrite _ -> failwith "TODO/Invalid: Have not decided whether rewrite \":[x]\" is useful."
-  in
-  List.fold predicates ~init:(true, None) ~f:(fun (sat, out) predicate ->
-      if sat then
-        let env =
-          Option.value_map out
-            ~f:(fun out -> Environment.merge out env)
-            ~default:env
-        in
-        rule_match env predicate
-      else
-        (sat, out))

lib/kernel/language/rule.ml

@@ -2,5 +2,4 @@ include Types
 
 let create = Parser.create
 
-module Alpha = Alpha_rule
-module Omega = Omega_rule
+include Evaluate

lib/kernel/language/rule.mli

@@ -4,5 +4,4 @@ include module type of Types
 
 val create : string -> t Or_error.t
 
-module Alpha : Engine
-module Omega : Engine
+include Engine

src/main.ml

@@ -227,6 +227,7 @@ let base_command_parameters : (unit -> 'result) Command.Param.t =
             ; override_matcher
             ; regex_pattern
             ; ripgrep_args
+            ; omega
             }
         ; run_options =
             { verbose
@@ -234,7 +235,6 @@ let base_command_parameters : (unit -> 'result) Command.Param.t =
             ; dump_statistics
             ; substitute_in_place
             ; disable_substring_matching
-            ; omega
             ; fast_offset_conversion
             ; match_newline_toplevel
             ; bound_count

test/common/test_alpha.ml

@@ -1,5 +1,2 @@
-open Language
-
 include Matchers.Alpha
-let create = Language.Rule.create
-module Rule = Rule.Alpha
+module Rule = Language.Rule

test/common/test_go_alpha.ml

@@ -15,7 +15,8 @@ let run ?(rule = "where true") source match_template rewrite_template =
     if Rule.(sat @@ apply rule environment) then
       Rewrite.all ~source ~rewrite_template [result]
       |> (fun x -> Option.value_exn x)
-      |> (fun { rewritten_source; _ } -> rewritten_source)    |> print_string
+      |> (fun { rewritten_source; _ } -> rewritten_source)
+      |> print_string
     else
       assert false
   | Error _ ->

test/common/test_go_omega.ml

@@ -15,7 +15,8 @@ let run ?(rule = "where true") source match_template rewrite_template =
     if Rule.(sat @@ apply rule environment) then
       Rewrite.all ~source ~rewrite_template [result]
       |> (fun x -> Option.value_exn x)
-      |> (fun { rewritten_source; _ } -> rewritten_source)    |> print_string
+      |> (fun { rewritten_source; _ } -> rewritten_source)
+      |> print_string
     else
       assert false
   | Error _ ->

test/common/test_helpers.ml

@@ -1,7 +1,8 @@
 open Core
-open Matchers
 
-let configuration = Configuration.create ~match_kind:Fuzzy ()
+open Rewriter
+
+let configuration = Matchers.Configuration.create ~match_kind:Fuzzy ()
 
 let format s =
   let s = String.chop_prefix_exn ~prefix:"\n" s in
@@ -23,3 +24,50 @@ let print_only_match matches =
   |> (fun matches -> `List matches)
   |> Yojson.Safe.pretty_to_string
   |> print_string
+
+let run ?(configuration = configuration) (module M : Matchers.Matcher.S) source match_template ?rule rewrite_template =
+  let rule =
+    match rule with
+    | Some rule -> Language.Rule.create rule |> Or_error.ok_exn
+    | None -> Language.Rule.create "where true" |> Or_error.ok_exn
+  in
+  M.all ~configuration ~template:match_template ~source ()
+  |> List.filter ~f:(fun { Match.environment; _ } -> Language.Rule.(sat @@ apply rule environment))
+  |> function
+  | [] -> print_string "No matches."
+  | results ->
+    Option.value_exn (Rewrite.all ~source ~rewrite_template results)
+    |> (fun { rewritten_source; _ } -> rewritten_source)
+    |> print_string
+
+let run_nested
+    (module M : Matchers.Matcher.S)
+    ?(configuration = configuration)
+    ?rule
+    source
+    match_template
+    () =
+  let nested =
+    match rule with
+    | None -> true
+    | Some rule ->
+      let options = Language.Rule.create rule |> Or_error.ok_exn |> Language.Rule.options in
+      options.nested
+  in
+  M.all ~configuration ~nested ~template:match_template ~source ()
+  |> function
+  | [] -> print_string "No matches."
+  | matches ->
+    let matches = List.map matches ~f:(Match.convert_offset ~fast:true ~source) in
+    Format.asprintf "%a" Match.pp (None, matches)
+    |> print_string
+
+(** Rule tests *)
+let sat ?(env = Match.Environment.create ()) rule =
+  let rule = Language.Rule.create rule |> Or_error.ok_exn in
+  Format.sprintf "%b" (Language.Rule.(sat @@ apply rule env))
+
+let make_env bindings =
+  List.fold bindings
+    ~init:(Match.Environment.create ())
+    ~f:(fun env (var, value) -> Match.Environment.add env var value)

test/common/test_match_rule_alpha.ml

@@ -1,21 +1,11 @@
 open Core
 
-open Matchers
 open Match
 
 open Test_helpers
 
 include Test_alpha
 
-let sat ?(env = Environment.create ()) rule =
-  let rule = create rule |> Or_error.ok_exn in
-  Format.sprintf "%b" (Rule.(sat @@ apply rule env))
-
-let make_env bindings =
-  List.fold bindings
-    ~init:(Environment.create ())
-    ~f:(fun env (var, value) -> Environment.add env var value)
-
 let%expect_test "rule_sat" =
   let rule = {| where "x" != "y" |} in
   sat rule |> print_string;
@@ -60,19 +50,6 @@ let%expect_test "rule_sat_with_env" =
   sat ~env rule |> print_string;
   [%expect_exact {|false|}]
 
-let configuration = Configuration.create ~match_kind:Fuzzy ()
-
-let format s =
-  let s = s |> String.chop_prefix_exn ~prefix:"\n" in
-  let leading_indentation =
-    Option.value_exn (String.lfindi s ~f:(fun _ c -> not (Char.equal c ' '))) in
-  s
-  |> String.split ~on:'\n'
-  |> List.map ~f:(Fn.flip String.drop_prefix leading_indentation)
-  |> String.concat ~sep:"\n"
-  |> String.chop_suffix_exn ~suffix:"\n"
-
-
 let%expect_test "where_true" =
   let template =
     {|
@@ -91,7 +68,7 @@ let%expect_test "where_true" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -140,7 +117,7 @@ let%expect_test "match_sat" =
        | ":[_],:[_]" -> false
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -156,7 +133,7 @@ let%expect_test "match_sat" =
        | ":[_],:[_]" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -199,7 +176,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -235,7 +212,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> :[1] == "a"
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -270,7 +247,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> :[1] == "b"
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -289,7 +266,7 @@ let%expect_test "match_s_suffix" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -325,7 +302,7 @@ let%expect_test "match_s_suffix" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -363,7 +340,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "ame" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -382,7 +359,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "names" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -419,7 +396,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "names" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -440,7 +417,7 @@ let%expect_test "match_using_environment_merge" =
   let rule =
     {| where match :[1] { | "{ :[x] : :[y] }" -> :[x] == :[y] }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -475,7 +452,7 @@ let%expect_test "match_using_environment_merge" =
   let rule =
     {| where match :[1] { | "{ :[x] : :[y] }" -> :[x] == :[y] }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -500,7 +477,7 @@ let%expect_test "nested_matches" =
                      }
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -541,7 +518,7 @@ let%expect_test "nested_matches" =
                      }
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -562,7 +539,7 @@ let%expect_test "match_on_template" =
        | "poodles" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -599,7 +576,7 @@ let%expect_test "match_on_template" =
        | "poodles" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -636,7 +613,7 @@ let%expect_test "match_on_template" =
        | "poodle" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 

test/common/test_match_rule_omega.ml

@@ -1,21 +1,11 @@
 open Core
 
-open Matchers
 open Match
 
 open Test_helpers
 
 include Test_omega
 
-let sat ?(env = Environment.create ()) rule =
-  let rule = create rule |> Or_error.ok_exn in
-  Format.sprintf "%b" (Rule.(sat @@ apply rule env))
-
-let make_env bindings =
-  List.fold bindings
-    ~init:(Environment.create ())
-    ~f:(fun env (var, value) -> Environment.add env var value)
-
 let%expect_test "rule_sat" =
   let rule = {| where "x" != "y" |} in
   sat rule |> print_string;
@@ -60,19 +50,6 @@ let%expect_test "rule_sat_with_env" =
   sat ~env rule |> print_string;
   [%expect_exact {|false|}]
 
-let configuration = Configuration.create ~match_kind:Fuzzy ()
-
-let format s =
-  let s = s |> String.chop_prefix_exn ~prefix:"\n" in
-  let leading_indentation =
-    Option.value_exn (String.lfindi s ~f:(fun _ c -> not (Char.equal c ' '))) in
-  s
-  |> String.split ~on:'\n'
-  |> List.map ~f:(Fn.flip String.drop_prefix leading_indentation)
-  |> String.concat ~sep:"\n"
-  |> String.chop_suffix_exn ~suffix:"\n"
-
-
 let%expect_test "where_true" =
   let template =
     {|
@@ -91,7 +68,7 @@ let%expect_test "where_true" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -140,7 +117,7 @@ let%expect_test "match_sat" =
        | ":[_],:[_]" -> false
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -156,7 +133,7 @@ let%expect_test "match_sat" =
        | ":[_],:[_]" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -199,7 +176,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -235,7 +212,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> :[1] == "a"
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -270,7 +247,7 @@ let%expect_test "match_sat" =
        | ":[_]" -> :[1] == "b"
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -289,7 +266,7 @@ let%expect_test "match_s_suffix" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -325,7 +302,7 @@ let%expect_test "match_s_suffix" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -363,7 +340,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "ame" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -382,7 +359,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "names" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -419,7 +396,7 @@ let%expect_test "configuration_choice_based_on_case" =
        | "names" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -440,7 +417,7 @@ let%expect_test "match_using_environment_merge" =
   let rule =
     {| where match :[1] { | "{ :[x] : :[y] }" -> :[x] == :[y] }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -475,7 +452,7 @@ let%expect_test "match_using_environment_merge" =
   let rule =
     {| where match :[1] { | "{ :[x] : :[y] }" -> :[x] == :[y] }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -500,7 +477,7 @@ let%expect_test "nested_matches" =
                      }
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -541,7 +518,7 @@ let%expect_test "nested_matches" =
                      }
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -562,7 +539,7 @@ let%expect_test "match_on_template" =
        | "poodles" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -599,7 +576,7 @@ let%expect_test "match_on_template" =
        | "poodles" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -636,7 +613,7 @@ let%expect_test "match_on_template" =
        | "poodle" -> true
        }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 

test/common/test_nested_matches_alpha.ml

@@ -4,28 +4,7 @@ open Test_helpers
 
 include Test_alpha
 
-let run
-    ?(m = (module Generic : Matchers.Matcher.S))
-    ?(configuration = configuration)
-    ?rule
-    source
-    match_template
-    () =
-  let (module M) = m in
-  let nested =
-    match rule with
-    | None -> true
-    | Some rule ->
-      let options = create rule |> Or_error.ok_exn |> Rule.options in
-      options.nested
-  in
-  M.all ~configuration ~nested ~template:match_template ~source ()
-  |> function
-  | [] -> print_string "No matches."
-  | matches ->
-    let matches = List.map matches ~f:(Match.convert_offset ~fast:true ~source) in
-    Format.asprintf "%a" Match.pp (None, matches)
-    |> print_string
+let run = run_nested (module Matchers.Alpha.Generic)
 
 let%expect_test "nested_matches" =
   let source = {|

test/common/test_nested_matches_omega.ml

@@ -2,30 +2,7 @@ open Core
 
 open Test_helpers
 
-include Test_omega
-
-let run
-    ?(m = (module Generic : Matchers.Matcher.S))
-    ?(configuration = configuration)
-    ?rule
-    source
-    match_template
-    () =
-  let (module M) = m in
-  let nested =
-    match rule with
-    | None -> true
-    | Some rule ->
-      let options = create rule |> Or_error.ok_exn |> Rule.options in
-      options.nested
-  in
-  M.all ~configuration ~nested ~template:match_template ~source ()
-  |> function
-  | [] -> print_string "No matches."
-  | matches ->
-    let matches = List.map matches ~f:(Match.convert_offset ~fast:true ~source) in
-    Format.asprintf "%a" Match.pp (None, matches)
-    |> print_string
+let run = run_nested (module Matchers.Omega.Generic)
 
 let%expect_test "nested_matches" =
   let source = {|

test/common/test_omega.ml

@@ -1,5 +1,2 @@
-open Language
-
 include Matchers.Omega
-let create = Language.Rule.create
-module Rule = Rule.Omega
+module Rule = Language.Rule

test/common/test_pipeline_alpha.ml

@@ -13,7 +13,6 @@ let configuration =
       ; dump_statistics = false
       ; substitute_in_place = true
       ; disable_substring_matching = false
-      ; omega = false
       ; fast_offset_conversion = false
       ; match_newline_toplevel = false
       ; bound_count = None
@@ -25,12 +24,6 @@ let configuration =
   ; metasyntax = None
   }
 
-let configuration =
-  { configuration with
-    run_options =
-      { configuration.run_options with omega = false }
-  }
-
 (* TODO restore this, can't access the Parallel_hack module *)
 (*
 let%expect_test "interactive_paths" =

test/common/test_pipeline_omega.ml

@@ -13,7 +13,6 @@ let configuration =
       ; dump_statistics = false
       ; substitute_in_place = true
       ; disable_substring_matching = false
-      ; omega = false
       ; fast_offset_conversion = false
       ; match_newline_toplevel = false
       ; bound_count = None
@@ -25,12 +24,6 @@ let configuration =
   ; metasyntax = None
   }
 
-let configuration =
-  { configuration with
-    run_options =
-      { configuration.run_options with omega = true }
-  }
-
 (* TODO restore this, can't access the Parallel_hack module *)
 (*
 let%expect_test "interactive_paths" =

test/common/test_regex_holes_alpha.ml

@@ -1,26 +1,8 @@
 open Core
 
-open Rewriter
-
+open Test_helpers
 open Matchers.Alpha
 
-let configuration = Matchers.Configuration.create ~match_kind:Fuzzy ()
-
-let run ?(configuration = configuration) (module M : Matchers.Matcher.S) source match_template ?rule rewrite_template =
-  let rule =
-    match rule with
-    | Some rule -> Language.Rule.create rule |> Or_error.ok_exn
-    | None -> Language.Rule.create "where true" |> Or_error.ok_exn
-  in
-  M.all ~configuration ~template:match_template ~source ()
-  |> List.filter ~f:(fun { Match.environment; _ } -> Language.Rule.Alpha.(sat @@ apply rule environment))
-  |> function
-  | [] -> print_string "No matches."
-  | results ->
-    Option.value_exn (Rewrite.all ~source ~rewrite_template results)
-    |> (fun { rewritten_source; _ } -> rewritten_source)
-    |> print_string
-
 let%expect_test "regex_holes_simple" =
   let source = {|foo|} in
   let match_template = {|:[x~\w+]|} in

test/common/test_regex_holes_omega.ml

@@ -1,26 +1,8 @@
 open Core
 
-open Rewriter
-
+open Test_helpers
 open Matchers.Omega
 
-let configuration = Matchers.Configuration.create ~match_kind:Fuzzy ()
-
-let run ?(configuration = configuration) (module M : Matchers.Matcher.S) source match_template ?rule rewrite_template =
-  let rule =
-    match rule with
-    | Some rule -> Language.Rule.create rule |> Or_error.ok_exn
-    | None -> Language.Rule.create "where true" |> Or_error.ok_exn
-  in
-  M.all ~configuration ~template:match_template ~source ()
-  |> List.filter ~f:(fun { Match.environment; _ } -> Language.Rule.Alpha.(sat @@ apply rule environment))
-  |> function
-  | [] -> print_string "No matches."
-  | results ->
-    Option.value_exn (Rewrite.all ~source ~rewrite_template results)
-    |> (fun { rewritten_source; _ } -> rewritten_source)
-    |> print_string
-
 let%expect_test "regex_holes_simple" =
   let source = {|foo|} in
   let match_template = {|:[x~\w+]|} in

test/common/test_rewrite_rule_alpha.ml

@@ -34,7 +34,7 @@ let%expect_test "rewrite_rule" =
     {|
       where rewrite :[1] { "int" -> "expect" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -52,7 +52,7 @@ let%expect_test "sequenced_rewrite_rule" =
       rewrite :[a] { "a" -> "qqq" },
       rewrite :[rest] { "{ b : { :[other] } }" -> "{ :[other] }" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -68,7 +68,7 @@ let%expect_test "rewrite_rule_for_list" =
     {|
       where rewrite :[contents] { ":[[x]]," -> ":[[x]];" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -84,7 +84,7 @@ let%expect_test "rewrite_rule_for_list_strip_last" =
     {|
       where rewrite :[contents] { ":[x], " -> ":[x]; " }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -105,7 +105,7 @@ let%expect_test "haskell_example" =
     {|
       where rewrite :[contents] { "," -> "++" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -129,7 +129,7 @@ let%expect_test "rewrite_freeform_antecedent_pattern" =
     {|
       where rewrite :[contents] { concat [:[x]] -> "nice" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 

test/common/test_rewrite_rule_omega.ml

@@ -34,7 +34,7 @@ let%expect_test "rewrite_rule" =
     {|
       where rewrite :[1] { "int" -> "expect" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -52,7 +52,7 @@ let%expect_test "sequenced_rewrite_rule" =
       rewrite :[a] { "a" -> "qqq" },
       rewrite :[rest] { "{ b : { :[other] } }" -> "{ :[other] }" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -68,7 +68,7 @@ let%expect_test "rewrite_rule_for_list" =
     {|
       where rewrite :[contents] { ":[[x]]," -> ":[[x]];" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -84,7 +84,7 @@ let%expect_test "rewrite_rule_for_list_strip_last" =
     {|
       where rewrite :[contents] { ":[x], " -> ":[x]; " }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -105,7 +105,7 @@ let%expect_test "haskell_example" =
     {|
       where rewrite :[contents] { "," -> "++" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 
@@ -129,7 +129,7 @@ let%expect_test "rewrite_freeform_antecedent_pattern" =
     {|
       where rewrite :[contents] { concat [:[x]] -> "nice" }
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
 

test/common/test_statistics.ml

@@ -28,7 +28,7 @@ let %expect_test "statistics" =
   let rule =
     {| where true
     |}
-    |> create
+    |> Language.Rule.create
     |> Or_error.ok_exn
   in
   Go.all ~configuration ~template ~source ()