fix: test for ios range line break error (#2635)

src/core/features.ts

@@ -1,3 +1,5 @@
+import {fromCodePoint, toCodePoints} from 'css-line-break';
+
 const testRangeBounds = (document: Document) => {
     const TEST_HEIGHT = 123;
 
@@ -22,6 +24,45 @@ const testRangeBounds = (document: Document) => {
     return false;
 };
 
+const testIOSLineBreak = (document: Document) => {
+    const testElement = document.createElement('boundtest');
+    testElement.style.width = '50px';
+    testElement.style.display = 'block';
+    testElement.style.fontSize = '12px';
+    testElement.style.letterSpacing = '0px';
+    testElement.style.wordSpacing = '0px';
+    document.body.appendChild(testElement);
+    const range = document.createRange();
+
+    testElement.innerHTML = typeof ''.repeat === 'function' ? '👨'.repeat(10) : '';
+
+    const node = testElement.firstChild as Text;
+
+    const textList = toCodePoints(node.data).map((i) => fromCodePoint(i));
+    let offset = 0;
+    let prev: DOMRect = {} as DOMRect;
+
+    // ios 13 does not handle range getBoundingClientRect line changes correctly #2177
+    const supports = textList.every((text, i) => {
+        range.setStart(node, offset);
+        range.setEnd(node, offset + text.length);
+        const rect = range.getBoundingClientRect();
+
+        offset += text.length;
+        const boundAhead = rect.x > prev.x || rect.y > prev.y;
+
+        prev = rect;
+        if (i === 0) {
+            return true;
+        }
+
+        return boundAhead;
+    });
+
+    document.body.removeChild(testElement);
+    return supports;
+};
+
 const testCORS = (): boolean => typeof new Image().crossOrigin !== 'undefined';
 
 const testResponseType = (): boolean => typeof new XMLHttpRequest().responseType === 'string';
@@ -132,6 +173,12 @@ export const FEATURES = {
         Object.defineProperty(FEATURES, 'SUPPORT_RANGE_BOUNDS', {value});
         return value;
     },
+    get SUPPORT_WORD_BREAKING(): boolean {
+        'use strict';
+        const value = FEATURES.SUPPORT_RANGE_BOUNDS && testIOSLineBreak(document);
+        Object.defineProperty(FEATURES, 'SUPPORT_WORD_BREAKING', {value});
+        return value;
+    },
     get SUPPORT_SVG_DRAWING(): boolean {
         'use strict';
         const value = testSVG(document);