fix extra grout issue in #84

src/core/editor/Modify.re

@@ -151,7 +151,7 @@ let rec remold = (~fill=Cell.dirty, ctx: Ctx.t): (Cell.t, Ctx.t) => {
 
 let finalize = (~mode=Mode.Navigating, ~fill=Cell.dirty, ctx: Ctx.t): Zipper.t => {
   Mode.set(mode);
-  // P.log("--- finalize");
+  // P.log("--- Modify.finalize");
   let (remolded, ctx) = remold(~fill, ctx);
   // P.show("remolded", Cell.show(remolded));
   // P.show("ctx", Ctx.show(ctx));
@@ -245,6 +245,7 @@ let expand = (tok: Token.t) =>
   };
 let try_expand = (s: string, z: Zipper.t): option(Zipper.t) => {
   open Options.Syntax;
+  // P.log("--- Modify.try_expand");
   let* () = Options.of_bool(String.starts_with(~prefix=" ", s));
   // todo: check if in middle of token
   let (face, rest) = Ctx.pull(~from=L, z.ctx);
@@ -253,6 +254,9 @@ let try_expand = (s: string, z: Zipper.t): option(Zipper.t) => {
   let* expanded = expand(tok);
   let ((l, r), tl) = Ctx.unlink_stacks(rest);
   let* (t, grouted, rest) = Result.to_option(Molder.mold(l, expanded));
+  // P.show("molded", Token.show(t));
+  // P.show("grouted", Grouted.show(grouted));
+  // P.show("stack", Stack.show(rest));
   if (t.mtrl == Space(Unmolded) || t.mtrl == tok.mtrl) {
     None;
   } else {

src/core/material/Walk.re

@@ -80,7 +80,11 @@ module T = {
 
   let is_eq = w => List.for_all(Swing.is_eq, Chain.loops(w));
   // note: stricter than !is_eq
-  let is_neq = (w: t) => Swing.is_neq(hd(w)) && Swing.is_neq(ft(w));
+  // strict=true further requires ft swing to be neq, as a way to avoid
+  // generating matching ghosts from the start end of the walk (this is
+  // useful for preserving bidelimited containers)
+  let is_neq = (~strict=false, w: t) =>
+    Swing.is_neq(hd(w)) && (!strict || Swing.is_neq(ft(w)));
   let is_valid = w => is_eq(w) || is_neq(w);
 
   // let has_sort = w => List.exists(Swing.has_sort, strides(w));

src/core/material/Walker.re

@@ -258,8 +258,8 @@ let walk = (~from: Dir.t, src: End.t, dst: End.t) =>
   Index.find(dst, walk_all(~from, src));
 let walk_eq = (~from: Dir.t, src: End.t, dst: End.t) =>
   List.filter(Walk.is_eq, walk(~from, src, dst));
-let walk_neq = (~from: Dir.t, src: End.t, dst: End.t) =>
-  List.filter(Walk.is_neq, walk(~from, src, dst));
+let walk_neq = (~strict=true, ~from: Dir.t, src: End.t, dst: End.t) =>
+  List.filter(Walk.is_neq(~strict), walk(~from, src, dst));
 
 let enter = (~from: Dir.t, sort: Mtrl.NT.t, dst: End.t) =>
   Index.find(dst, enter_all(~from, sort));

src/core/parser/Melder.re

@@ -104,6 +104,7 @@ let connect_eq =
 };
 let connect_neq =
     (
+      ~strict=false,
       ~repair=false,
       ~onto as d: Dir.t,
       onto: Bound.t(Terr.t),
@@ -112,7 +113,7 @@ let connect_neq =
     )
     : option(Grouted.t) => {
   let face = onto |> Bound.map(t => Terr.face(t).mtrl);
-  Walker.walk_neq(~from=d, face, Node(t.mtrl))
+  Walker.walk_neq(~strict, ~from=d, face, Node(t.mtrl))
   |> Grouter.pick(~repair, ~from=d, [fill]);
 };
 let connect_lt = connect_neq(~onto=L);
@@ -132,7 +133,9 @@ let connect_ineq =
     |> Options.bind(~f=onto => connect_eq(~repair, ~onto=d, onto, ~fill, t))
     |> Option.map(((grouted, terr)) => (grouted, Bound.Node(terr)));
   let neq = () =>
-    connect_neq(~repair, ~onto=d, onto, ~fill, t)
+    // require strict neq when we reach the stack bound to avoid breaking
+    // bidelimited containers
+    connect_neq(~strict=true, ~repair, ~onto=d, onto, ~fill, t)
     |> Option.map(grouted => (grouted, onto));
   if (repair) {
     open Options.Syntax;

src/core/parser/Molder.re

@@ -150,13 +150,21 @@ and remold =
            (c, up);
          })
       |> Option.value(~default=Slope.Up.unroll(hd.cell));
+    // P.log("--- Molder.remold/continue/molding");
+    // P.show("l", Stack.show(l));
+    // P.show("fill", Cell.show(fill));
+    // P.show("hd_w", Token.show(hd_w));
     switch (mold(l, ~fill, Token.unmold(hd_w))) {
     | Error(fill) =>
       let (c, up) = unroll_tl_w_hd_cell();
       let fill = fill |> Cell.pad(~r=c) |> Cell.mark_ends_dirty;
       (l, r_tl) |> Stack.Frame.cat(([], up)) |> remold(~fill);
     | Ok((t, grouted, rest)) when t.mtrl == hd_w.mtrl =>
       // fast path for when hd_w retains original meld
+      // P.log("--- Molder.remold/continue/fast path");
+      // P.show("t", Token.show(t));
+      // P.show("grouted", Grouted.show(grouted));
+      // P.show("rest", Stack.show(rest));
       let connected = Stack.connect(t, grouted, rest) |> Stack.extend(tl_w);
       if (connected.bound == l.bound) {
         remold(~fill=hd.cell, (connected, r_tl));