fix delete forward/backward to be unicode aware, closes #87

lib/plugins/core.js

@@ -2,9 +2,9 @@
 import Key from '../utils/key'
 import Placeholder from '../components/placeholder'
 import React from 'react'
+import String from '../utils/string'
 import keycode from 'keycode'
 import { IS_WINDOWS, IS_MAC } from '../utils/environment'
-import { getWordOffsetBackward, getWordOffsetForward } from '../utils/string'
 
 /**
  * The default plugin.
@@ -156,14 +156,16 @@ function Plugin(options = {}) {
 
         case 'backspace': {
           if (state.isExpanded) return transform.delete().apply()
-
+          const { startOffset, startBlock } = state
+          const text = startBlock.text
           let n
+
           if (Key.isWord(e)) {
-            n = getWordOffsetBackward(state.startBlock.text, state.startOffset)
+            n = String.getWordOffsetBackward(text, startOffset)
           } else if (Key.isLine(e)) {
-            n = state.startOffset
+            n = startOffset
           } else {
-            n = 1
+            n = String.getCharOffsetBackward(text, startOffset)
           }
 
           return transform.deleteBackward(n).apply()
@@ -171,14 +173,16 @@ function Plugin(options = {}) {
 
         case 'delete': {
           if (state.isExpanded) return transform.delete().apply()
-
+          const { startOffset, startBlock } = state
+          const text = startBlock.text
           let n
+
           if (Key.isWord(e)) {
-            n = getWordOffsetForward(state.startBlock.text, state.startOffset)
+            n = String.getWordOffsetForward(text, startOffset)
           } else if (Key.isLine(e)) {
-            n = state.startBlock.text.length - state.startOffset
+            n = text.length - startOffset
           } else {
-            n = 1
+            n = String.getCharOffsetForward(text, startOffset)
           }
 
           return transform.deleteForward(n).apply()

lib/utils/string.js

@@ -60,7 +60,7 @@ function isWord(char, remaining) {
   // If it's a chameleon character, recurse to see if the next one is or not.
   if (CHAMELEON.test(char)) {
     const next = remaining.charAt(0)
-    const length = getCharacterLength(next)
+    const length = getCharLength(next)
     const rest = remaining.slice(length)
     if (isWord(next, rest)) return true
   }
@@ -76,12 +76,51 @@ function isWord(char, remaining) {
  * @return {Number}
  */
 
-function getCharacterLength(char) {
+function getCharLength(char) {
   return isSurrogate(char.charCodeAt(0))
     ? 2
     : 1
 }
 
+/**
+ * Get the offset to the end of the first character in `text`.
+ *
+ * @param {String} text
+ * @return {Number}
+ */
+
+function getCharOffset(text) {
+  const char = text.charAt(0)
+  return getCharLength(char)
+}
+
+/**
+ * Get the offset to the end of the character before an `offset` in `text`.
+ *
+ * @param {String} text
+ * @param {Number} offset
+ * @return {Number}
+ */
+
+function getCharOffsetBackward(text, offset) {
+  text = text.slice(0, offset)
+  text = reverse(text)
+  return getCharOffset(text)
+}
+
+/**
+ * Get the offset to the end of the character after an `offset` in `text`.
+ *
+ * @param {String} text
+ * @param {Number} offset
+ * @return {Number}
+ */
+
+function getCharOffsetForward(text, offset) {
+  text = text.slice(offset)
+  return getCharOffset(text)
+}
+
 /**
  * Get the length of a `string`.
  *
@@ -95,7 +134,7 @@ function getLength(string) {
   for (
     let i = 0, char = string.charAt(i);
     i < string.length;
-    i += getCharacterLength(char)
+    i += getCharLength(char)
   ) {
     length++
   }
@@ -104,34 +143,7 @@ function getLength(string) {
 }
 
 /**
- * Get the offset at the end of the word before an `offset` in `text`.
- *
- * @param {String} text
- * @param {Number} offset
- * @return {Number}
- */
-
-function getWordOffsetBackward(text, offset) {
-  text = text.slice(0, offset)
-  text = reverse(text)
-  return getWordOffset(text)
-}
-
-/**
- * Get the offset at the end of the word after an `offset` in `text`.
- *
- * @param {String} text
- * @param {Number} offset
- * @return {Number}
- */
-
-function getWordOffsetForward(text, offset) {
-  text = text.slice(offset)
-  return getWordOffset(text)
-}
-
-/**
- * Get the offset at the end of the first word in `text`.
+ * Get the offset to the end of the first word in `text`.
  *
  * @param {String} text
  * @return {Number}
@@ -144,7 +156,7 @@ function getWordOffset(text) {
   let char
 
   while (char = text.charAt(i)) {
-    const l = getCharacterLength(char)
+    const l = getCharLength(char)
     const rest = text.slice(i + l)
 
     if (isWord(char, rest)) {
@@ -162,11 +174,40 @@ function getWordOffset(text) {
   return length
 }
 
+/**
+ * Get the offset to the end of the word before an `offset` in `text`.
+ *
+ * @param {String} text
+ * @param {Number} offset
+ * @return {Number}
+ */
+
+function getWordOffsetBackward(text, offset) {
+  text = text.slice(0, offset)
+  text = reverse(text)
+  return getWordOffset(text)
+}
+
+/**
+ * Get the offset to the end of the word after an `offset` in `text`.
+ *
+ * @param {String} text
+ * @param {Number} offset
+ * @return {Number}
+ */
+
+function getWordOffsetForward(text, offset) {
+  text = text.slice(offset)
+  return getWordOffset(text)
+}
+
 /**
  * Export.
  */
 
-export {
+export default {
+  getCharOffsetForward,
+  getCharOffsetBackward,
   getWordOffsetBackward,
   getWordOffsetForward
 }