change utils.sml to run using rope (with line metadata) instead of tiny_rope, and verify that line metadata is correct

rope.sml

@@ -7,6 +7,8 @@ sig
   val toString: t -> string
   val foldr: ('a * string * int vector -> 'a) * 'a * t -> 'a
 
+  (* The caller should not insert in the middle of a \r\n pair,
+   * or else line metadata will become invalid. *)
   val insert: int * string * t -> t
 
   (* The append and appendLine function both add a string to the end.
@@ -16,6 +18,8 @@ sig
   val append: string * t -> t
   val appendLine: string * int vector * t -> t
 
+  (* The caller should not delete only a single character in a \r\n pair,
+   * because then line metadata will become invalid. *)
   val delete: int * int * t -> t
 
   (* This below function verifies that line metadata is as expected,
@@ -546,6 +550,15 @@ struct
     in endInsert (rope, action)
     end
 
+  fun isDelLessThanTarget (str1, str2, vec, startPoint, endPoint) =
+    let
+      val vecLength = Vector.length vec - (endPoint - startPoint)
+    in
+      String.size str1 + String.size str2 <= targetLength
+      andalso vecLength <= targetVecLength
+    end
+
+
   fun delLeaf (startIdx, endIdx, str, vec) =
     if
       startIdx <= 0 andalso endIdx >= String.size str
@@ -563,7 +576,7 @@ struct
         val endPoint = binSearch (endIdx, vec, 0, vecLength)
         val difference = endIdx - startIdx
       in
-        if isLessThanTarget (sub1, sub2) then
+        if isDelLessThanTarget (sub1, sub2, vec, startPoint, endPoint) then
           let
             val str = sub1 ^ sub2
             val vecDifference = endPoint - startPoint
@@ -599,7 +612,7 @@ struct
     then
       let
         val str = String.substring (str, 0, startIdx)
-        val midPoint = binSearch (startIdx, vec, 0, vecLength)
+        val midPoint = binSearch (startIdx, vec, 0, Vector.length vec - 1)
         val vec =
           if Vector.length vec = 0 then emptyVec
           else Vector.tabulate (midPoint, fn idx => Vector.sub (vec, idx))
@@ -609,7 +622,7 @@ struct
     else
       let
         val str = String.substring (str, endIdx, String.size str - endIdx)
-        val midPoint = binSearch (endIdx, vec, 0, vecLength)
+        val midPoint = binSearch (endIdx, vec, 0, Vector.length vec - 1)
         val vec =
           if Vector.length vec = 0 then
             emptyVec
@@ -642,10 +655,11 @@ struct
             val (l, _) = del (startIdx, endIdx, l)
             val (r, _) = del (startIdx - lms, endIdx - lms, r)
           in
-            makeN2 (l, r)
+            (makeN2 (l, r), false)
           end
     | N1 t => del (startIdx, endIdx, t)
     | N0 (str, vec) => delLeaf (startIdx, endIdx, str, vec)
+    | _ => raise AuxConstructor
 
   fun delete (start, length, rope) =
     let val (rope, didIns) = del (start, start + length, rope)

tiny_rope.sml

@@ -305,10 +305,8 @@ struct
         else (L2 (sub1, sub2), true)
       end
     else if startIdx >= 0 andalso endIdx >= String.size str then
-      let
-        val str = String.substring (str, 0, startIdx)
-      in
-        (N0 str, false)
+      let val str = String.substring (str, 0, startIdx)
+      in (N0 str, false)
       end
     else
       let val str = String.substring (str, endIdx, String.size str - endIdx)

utils.sml

@@ -1,13 +1,13 @@
 fun time_func title f =
   let
-    val title = String.concat ["Starting " , title , "..."]
+    val title = String.concat ["Starting ", title, "..."]
     val _ = (print title)
-    val start_time = Time.now()
+    val start_time = Time.now ()
     val start_time = Time.toNanoseconds start_time
-    val x = f()
-    val end_time = Time.now()
+    val x = f ()
+    val end_time = Time.now ()
     val end_time = Time.toNanoseconds end_time
-    val time_diff = end_time - start_time 
+    val time_diff = end_time - start_time
     val time_diff = LargeInt.toString time_diff
     val time_took = String.concat ["took ", time_diff, " nanoseconds\n"]
     val _ = (print time_took)
@@ -16,38 +16,28 @@ fun time_func title f =
   end
 
 fun run_txns arr =
-  Vector.foldl 
+  Vector.foldl
     (fn ((pos, del_num, ins_str), rope) =>
-      let
-        val rope = 
-          if del_num > 0 
-          then TinyRope.delete(pos, del_num, rope)
-          else rope
-        val str_size = String.size ins_str
-        val rope = 
-          if str_size > 0 
-          then TinyRope.insert(pos, ins_str, rope)
-          else rope
-      in
-        rope
-      end) 
-    TinyRope.empty arr
+       let
+         val rope =
+           if del_num > 0 then Rope.delete (pos, del_num, rope) else rope
+         val str_size = String.size ins_str
+         val rope =
+           if str_size > 0 then Rope.insert (pos, ins_str, rope) else rope
+       in
+         rope
+       end) Rope.empty arr
 
-fun run_txns_time title arr = 
-  let
-    val f = (fn () => run_txns arr)
-  in
-    time_func title f
+fun run_txns_time title arr =
+  let val f = (fn () => run_txns arr)
+  in time_func title f
   end
 
-fun run_to_string rope =
-  TinyRope.toString rope
+fun run_to_string rope = Rope.toString rope
 
 fun run_to_string_time title rope =
-  let
-    val f = (fn () => run_to_string rope)
-  in
-    time_func title f
+  let val f = (fn () => run_to_string rope)
+  in time_func title f
   end
 
 fun run_txns_1000_times (counter, arr, total) =
@@ -61,14 +51,14 @@ fun run_txns_1000_times (counter, arr, total) =
     end
   else
     let
-      val start_time = Time.now()
+      val start_time = Time.now ()
       val start_time = Time.toNanoseconds start_time
 
       val _ = run_txns arr
 
-      val end_time = Time.now()
+      val end_time = Time.now ()
       val end_time = Time.toNanoseconds end_time
-      val time_diff = end_time - start_time 
+      val time_diff = end_time - start_time
       val counter = counter + 1
       val total = time_diff + total
     in
@@ -76,7 +66,7 @@ fun run_txns_1000_times (counter, arr, total) =
     end
 
 fun write_file filename acc =
-  let 
+  let
     val str = String.concatWith "," acc
     val fd = TextIO.openOut filename
     val _ = TextIO.output (fd, str) handle e => (TextIO.closeOut fd; raise e)
@@ -85,16 +75,29 @@ fun write_file filename acc =
     ()
   end
 
-val _ =
+fun main () =
   let
+    (* Timing benchmarks. *)
     val start_time = LargeInt.fromInt 0
-    val svelte = run_txns_1000_times (999 ,svelte_arr, start_time )
+    val _ = run_txns_1000_times (999, svelte_arr, start_time)
+    val _ = run_txns_1000_times (999, rust_arr, start_time)
+    val _ = run_txns_1000_times (999, seph_arr, start_time)
+    val _ = run_txns_1000_times (999, automerge_arr, start_time)
 
-    val rust = run_txns_1000_times (999 ,rust_arr, start_time )
+    (* Tests that line metadata is correct; will fail if incorrect. *)
+    val svelte = run_txns svelte_arr
+    val _ = Rope.verifyLines svelte
 
-    val seph = run_txns_1000_times (999, seph_arr, start_time)
+    val rust = run_txns rust_arr
+    val _ = Rope.verifyLines rust
 
-    val automerge = run_txns_1000_times (999, automerge_arr , start_time)
+    val seph = run_txns seph_arr
+    val _ = Rope.verifyLines seph
+
+    val automerge = run_txns automerge_arr
+    val _ = Rope.verifyLines automerge
   in
     ()
   end
+
+val _ = main ()