Reorder less eagerly (#57)

Update findGap to search for gaps closer to the original position. Previously, we always searched towards the top of the document for gaps, which meant that you would reorder _up_ as soon as you overlapped with the node above you. Now, we weight searches by how far into the parent node the position is, so you don't reorder up until you've moved halfway up the node (by position).

Also we were checking `isTextblock` in findGap but we wanted `isBlock`.

Author: smoores-dev

.yarn/versions/49353831.yml

@@ -0,0 +1,2 @@
+releases:
+  "@pitter-patter/shuffle": patch

packages/shuffle/src/transform/reorder.ts

@@ -62,11 +62,20 @@ export function findGap(doc: Node, pos: number, nodeType: NodeType) {
   const $pos = doc.resolve(pos);
 
   let d = $pos.depth;
-  while (!$pos.node(d).isTextblock && d > 0) {
+  while (!$pos.node(d).isBlock && d > 0) {
     d--;
   }
 
-  const start = d === 0 ? pos : $pos.before(d);
+  if (d === 0) {
+    return pos;
+  }
+
+  const textblock = $pos.node(d);
+  const textblockPos = $pos.before(d);
+
+  const isInFirstHalf = pos <= textblockPos + textblock.nodeSize / 2;
+
+  const start = isInFirstHalf ? textblockPos : $pos.after(d);
 
   const gap = start ? insertPoint(doc, start, nodeType) : start;