feat: add Node.getIf method (#5723)

* feat: add Node.getIf support

* chore: restructure get to use getIf

.changeset/clean-icons-bow.md

@@ -0,0 +1,5 @@
+---
+'slate': patch
+---
+
+feat: add Node.getIf method

packages/slate/src/interfaces/node.ts

@@ -131,6 +131,11 @@ export interface NodeInterface {
  */
  get: (root: Node, path: Path) => Node
 
+ /**
+ * Similar to get, but returns undefined if the node does not exist.
+ */
+ getIf: (root: Node, path: Path) => Node | undefined
+
  /**
  * Check if a descendant node exists at a specific path.
  */
@@ -389,17 +394,25 @@ export const Node: NodeInterface = {
  },
 
  get(root: Node, path: Path): Node {
+ const node = Node.getIf(root, path)
+ if (node === undefined) {
+ throw new Error(
+ `Cannot find a descendant at path [${path}] in node: ${Scrubber.stringify(
+ root
+ )}`
+ )
+ }
+ return node
+ },
+
+ getIf(root: Node, path: Path): Node | undefined {
  let node = root
 
  for (let i = 0; i < path.length; i++) {
  const p = path[i]
 
  if (Text.isText(node) || !node.children[p]) {
- throw new Error(
- `Cannot find a descendant at path [${path}] in node: ${Scrubber.stringify(
- root
- )}`
- )
+ return
  }
 
  node = node.children[p]

packages/slate/test/interfaces/Node/getIf/root.tsx

@@ -0,0 +1,17 @@
+/** @jsx jsx */
+import { Node } from 'slate'
+import { jsx } from 'slate-hyperscript'
+import { cloneDeep } from 'lodash'
+
+export const input = (
+ <editor>
+ <element>
+ <text />
+ </element>
+ </editor>
+)
+export const test = value => {
+ return Node.getIf(value, [])
+}
+export const skip = true // TODO: see https://github.com/ianstormtaylor/slate/pull/4188
+export const output = cloneDeep(input)

packages/slate/test/interfaces/Node/getIf/success.tsx

@@ -0,0 +1,19 @@
+/** @jsx jsx */
+import { Node } from 'slate'
+import { jsx } from 'slate-hyperscript'
+
+export const input = (
+ <editor>
+ <element>
+ <text />
+ </element>
+ </editor>
+)
+export const test = value => {
+ return Node.getIf(value, [0])
+}
+export const output = (
+ <element>
+ <text />
+ </element>
+)

packages/slate/test/interfaces/Node/getIf/undefined.tsx

@@ -0,0 +1,15 @@
+/** @jsx jsx */
+import { Node } from 'slate'
+import { jsx } from 'slate-hyperscript'
+
+export const input = (
+ <editor>
+ <element>
+ <text />
+ </element>
+ </editor>
+)
+export const test = value => {
+ return Node.getIf(value, [0, 0, 0])
+}
+export const output = undefined