feat: sync selection to extactly matched DOM selection (#4157)

* feat: sync selection to extractly dom selection

* revert mistakenly modified files

* add changeset

* toSlatePoint will throw error again when not extractMatch

* Fix misspellings, rename extractMatch to exactMatch

* rename option to match code style

* Update four-poets-move.md

Co-authored-by: Ian Storm Taylor <ian@ianstormtaylor.com>

.changeset/four-poets-move.md

@@ -0,0 +1,5 @@
+---
+'slate-react': patch
+---
+
+Fixed a bug when syncing the selection for IME-based editing.

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

@@ -175,13 +175,13 @@ export const Editable = (props: EditableProps) => {
     }
 
     // If the DOM selection is in the editor and the editor selection is already correct, we're done.
-    if (
-      hasDomSelection &&
-      hasDomSelectionInEditor &&
-      selection &&
-      Range.equals(ReactEditor.toSlateRange(editor, domSelection), selection)
-    ) {
-      return
+    if (hasDomSelection && hasDomSelectionInEditor && selection) {
+      const slateRange = ReactEditor.toSlateRange(editor, domSelection, {
+        exactMatch: true,
+      })
+      if (slateRange && Range.equals(slateRange, selection)) {
+        return
+      }
     }
 
     // when <Editable/> is being controlled through external value
@@ -189,7 +189,9 @@ export const Editable = (props: EditableProps) => {
     // but Slate's value is not being updated through any operation
     // and thus it doesn't transform selection on its own
     if (selection && !ReactEditor.hasRange(editor, selection)) {
-      editor.selection = ReactEditor.toSlateRange(editor, domSelection)
+      editor.selection = ReactEditor.toSlateRange(editor, domSelection, {
+        exactMatch: false,
+      })
       return
     }
 
@@ -280,7 +282,9 @@ export const Editable = (props: EditableProps) => {
           const [targetRange] = (event as any).getTargetRanges()
 
           if (targetRange) {
-            const range = ReactEditor.toSlateRange(editor, targetRange)
+            const range = ReactEditor.toSlateRange(editor, targetRange, {
+              exactMatch: false,
+            })
 
             if (!selection || !Range.equals(selection, range)) {
               Transforms.select(editor, range)
@@ -444,7 +448,9 @@ export const Editable = (props: EditableProps) => {
           isTargetInsideVoid(editor, focusNode)
 
         if (anchorNodeSelectable && focusNodeSelectable) {
-          const range = ReactEditor.toSlateRange(editor, domSelection)
+          const range = ReactEditor.toSlateRange(editor, domSelection, {
+            exactMatch: false,
+          })
           Transforms.select(editor, range)
         } else {
           Transforms.deselect(editor)

packages/slate-react/src/plugin/react-editor.ts

@@ -432,7 +432,9 @@ export const ReactEditor = {
     }
 
     // Resolve a Slate range from the DOM range.
-    const range = ReactEditor.toSlateRange(editor, domRange)
+    const range = ReactEditor.toSlateRange(editor, domRange, {
+      exactMatch: false,
+    })
     return range
   },
 
@@ -440,8 +442,14 @@ export const ReactEditor = {
    * Find a Slate point from a DOM selection's `domNode` and `domOffset`.
    */
 
-  toSlatePoint(editor: ReactEditor, domPoint: DOMPoint): Point {
-    const [nearestNode, nearestOffset] = normalizeDOMPoint(domPoint)
+  toSlatePoint<T extends boolean>(
+    editor: ReactEditor,
+    domPoint: DOMPoint,
+    extractMatch: T
+  ): T extends true ? Point | null : Point {
+    const [nearestNode, nearestOffset] = extractMatch
+      ? domPoint
+      : normalizeDOMPoint(domPoint)
     const parentNode = nearestNode.parentNode as DOMElement
     let textNode: DOMElement | null = null
     let offset = 0
@@ -513,6 +521,9 @@ export const ReactEditor = {
     }
 
     if (!textNode) {
+      if (extractMatch) {
+        return null as T extends true ? Point | null : Point
+      }
       throw new Error(
         `Cannot resolve a Slate point from DOM point: ${domPoint}`
       )
@@ -523,17 +534,21 @@ export const ReactEditor = {
     // first, and then afterwards for the correct `element`. (2017/03/03)
     const slateNode = ReactEditor.toSlateNode(editor, textNode!)
     const path = ReactEditor.findPath(editor, slateNode)
-    return { path, offset }
+    return { path, offset } as T extends true ? Point | null : Point
   },
 
   /**
    * Find a Slate range from a DOM range or selection.
    */
 
-  toSlateRange(
+  toSlateRange<T extends boolean>(
     editor: ReactEditor,
-    domRange: DOMRange | DOMStaticRange | DOMSelection
-  ): Range {
+    domRange: DOMRange | DOMStaticRange | DOMSelection,
+    options: {
+      exactMatch: T
+    }
+  ): T extends true ? Range | null : Range {
+    const { exactMatch } = options
     const el = isDOMSelection(domRange)
       ? domRange.anchorNode
       : domRange.startContainer
@@ -580,12 +595,25 @@ export const ReactEditor = {
       )
     }
 
-    const anchor = ReactEditor.toSlatePoint(editor, [anchorNode, anchorOffset])
+    const anchor = ReactEditor.toSlatePoint(
+      editor,
+      [anchorNode, anchorOffset],
+      exactMatch
+    )
+    if (!anchor) {
+      return null as T extends true ? Range | null : Range
+    }
+
     const focus = isCollapsed
       ? anchor
-      : ReactEditor.toSlatePoint(editor, [focusNode, focusOffset])
+      : ReactEditor.toSlatePoint(editor, [focusNode, focusOffset], exactMatch)
+    if (!focus) {
+      return null as T extends true ? Range | null : Range
+    }
 
-    return { anchor, focus }
+    return ({ anchor, focus } as unknown) as T extends true
+      ? Range | null
+      : Range
   },
 
   hasRange(editor: ReactEditor, range: Range): boolean {