Allow all kinds of hole syntax in rewrite template

lib/rewriter/rewrite_template.ml

@@ -3,16 +3,25 @@ open Core
 open Match
 
 let substitute template env =
+  let substitution_formats =
+    [ ":[ ", "]"
+    ; ":[", ".]"
+    ; ":[", "\n]"
+    ; ":[[", "]]"
+    ; ":[", "]"
+    ]
+  in
   Environment.vars env
   |> List.fold ~init:(template, []) ~f:(fun (acc, vars) variable ->
       match Environment.lookup env variable with
       | Some value ->
-        if Option.is_some (String.substr_index template ~pattern:(":["^variable^"]")) then
-          (String.substr_replace_all acc ~pattern:(":["^variable^"]") ~with_:value, variable::vars)
-        else if Option.is_some (String.substr_index template ~pattern:(":[["^variable^"]]")) then
-          (String.substr_replace_all acc ~pattern:(":[["^variable^"]]") ~with_:value, variable::vars)
-        else
-          acc, vars
+        List.find_map substitution_formats ~f:(fun (left,right) ->
+            let pattern = left^variable^right in
+            if Option.is_some (String.substr_index template ~pattern) then
+              Some (String.substr_replace_all acc ~pattern ~with_:value, variable::vars)
+            else
+              None)
+        |> Option.value ~default:(acc,vars)
       | None -> acc, vars)
 
 let of_match_context

test/test_integration.ml

@@ -162,6 +162,41 @@ let%expect_test "single_token_match_inside_paren_no_succeeding_whitespace" =
   |> print_string;
   [%expect_exact "foo : bar"]
 
+let%expect_test "whitespace_hole_rewrite" =
+  let template = {|:[ w]this|} in
+  let rewrite_template = "space:[ w]here" in
+  let source = {|      this|} in
+  all template source
+  |> (fun matches -> Option.value_exn (Rewrite.all ~source ~rewrite_template matches))
+  |> (fun { rewritten_source; _ } -> rewritten_source)
+  |> print_string;
+  [%expect_exact "space      here"]
+
+let%expect_test "punctuation_hole_rewrite" =
+  let template = {|:[x.]|} in
+  let rewrite_template = "->:[x.]<-" in
+  let source = {|now.this. is,pod|racing|} in
+  all template source
+  |> (fun matches -> Option.value_exn (Rewrite.all ~source ~rewrite_template matches))
+  |> (fun { rewritten_source; _ } -> rewritten_source)
+  |> print_string;
+  [%expect_exact "->now.this.<- ->is,pod|racing<-"]
+
+let%expect_test "newline_hole_rewrite" =
+  let template = {|:[x\n]|} in
+  let rewrite_template = "->:[x\n]<-" in
+  let source = {|now.this.
+is,pod|racing
+|} in
+  all template source
+  |> (fun matches -> Option.value_exn (Rewrite.all ~source ~rewrite_template matches))
+  |> (fun { rewritten_source; _ } -> rewritten_source)
+  |> print_string;
+  [%expect_exact "->now.this.
+<-->is,pod|racing
+<-"]
+
+
 
 let%expect_test "shift_or_at_least_dont_get_stuck" =
   let template = ":[1]" in