moved getLeaves from react to slate core package and added some basic tests (#3358)

packages/slate-react/src/components/text.tsx

@@ -25,7 +25,7 @@ const Text = (props: {
   const { decorations, isLast, parent, renderLeaf, text } = props
   const editor = useEditor()
   const ref = useRef<HTMLSpanElement>(null)
-  const leaves = getLeaves(text, decorations)
+  const leaves = SlateText.decorations(text, decorations)
   const key = ReactEditor.findKey(editor, text)
   const children = []
 
@@ -63,79 +63,6 @@ const Text = (props: {
   )
 }
 
-/**
- * Get the leaves for a text node given decorations.
- */
-
-const getLeaves = (node: SlateText, decorations: Range[]): SlateText[] => {
-  let leaves: SlateText[] = [{ ...node }]
-
-  for (const dec of decorations) {
-    const { anchor, focus, ...rest } = dec
-    const [start, end] = Range.edges(dec)
-    const next = []
-    let o = 0
-
-    for (const leaf of leaves) {
-      const { length } = leaf.text
-      const offset = o
-      o += length
-
-      // If the range encompases the entire leaf, add the range.
-      if (start.offset <= offset && end.offset >= offset + length) {
-        Object.assign(leaf, rest)
-        next.push(leaf)
-        continue
-      }
-
-      // If the range starts after the leaf, or ends before it, continue.
-      if (
-        start.offset > offset + length ||
-        end.offset < offset ||
-        (end.offset === offset && offset !== 0)
-      ) {
-        next.push(leaf)
-        continue
-      }
-
-      // Otherwise we need to split the leaf, at the start, end, or both,
-      // and add the range to the middle intersecting section. Do the end
-      // split first since we don't need to update the offset that way.
-      let middle = leaf
-      let before
-      let after
-
-      if (end.offset < offset + length) {
-        const off = end.offset - offset
-        after = { ...middle, text: middle.text.slice(off) }
-        middle = { ...middle, text: middle.text.slice(0, off) }
-      }
-
-      if (start.offset > offset) {
-        const off = start.offset - offset
-        before = { ...middle, text: middle.text.slice(0, off) }
-        middle = { ...middle, text: middle.text.slice(off) }
-      }
-
-      Object.assign(middle, rest)
-
-      if (before) {
-        next.push(before)
-      }
-
-      next.push(middle)
-
-      if (after) {
-        next.push(after)
-      }
-    }
-
-    leaves = next
-  }
-
-  return leaves
-}
-
 const MemoizedText = React.memo(Text, (prev, next) => {
   return (
     next.parent === prev.parent &&