From f43f942fcd793dde9cdc6c0438f379ec3c05c405 Mon Sep 17 00:00:00 2001
From: Niklas von Hertzen <niklasvh@gmail.com>
Date: Mon, 9 Aug 2021 17:14:40 +0800
Subject: [PATCH] fix: test for ios range line break error (#2635)

---
 src/core/features.ts     | 47 ++++++++++++++++++++++++++++++++++++++++
 src/css/layout/bounds.ts | 14 ++++++++++++
 src/css/layout/text.ts   | 21 ++++++++++++++----
 3 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/src/core/features.ts b/src/core/features.ts
index 2b5f001..78514bd 100644
--- a/src/core/features.ts
+++ b/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' ? '&#128104;'.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);
diff --git a/src/css/layout/bounds.ts b/src/css/layout/bounds.ts
index 04596e3..43d1bea 100644
--- a/src/css/layout/bounds.ts
+++ b/src/css/layout/bounds.ts
@@ -15,6 +15,20 @@ export class Bounds {
             clientRect.height
         );
     }
+
+    static fromDOMRectList(context: Context, domRectList: DOMRectList): Bounds {
+        const domRect = domRectList[0];
+        return domRect
+            ? new Bounds(
+                  domRect.x + context.windowBounds.left,
+                  domRect.y + context.windowBounds.top,
+                  domRect.width,
+                  domRect.height
+              )
+            : Bounds.EMPTY;
+    }
+
+    static EMPTY = new Bounds(0, 0, 0, 0);
 }
 
 export const parseBounds = (context: Context, node: Element): Bounds => {
diff --git a/src/css/layout/text.ts b/src/css/layout/text.ts
index 2473926..9b33e7c 100644
--- a/src/css/layout/text.ts
+++ b/src/css/layout/text.ts
@@ -27,7 +27,16 @@ export const parseTextBounds = (
     textList.forEach((text) => {
         if (styles.textDecorationLine.length || text.trim().length > 0) {
             if (FEATURES.SUPPORT_RANGE_BOUNDS) {
-                textBounds.push(new TextBounds(text, getRangeBounds(context, node, offset, text.length)));
+                if (!FEATURES.SUPPORT_WORD_BREAKING) {
+                    textBounds.push(
+                        new TextBounds(
+                            text,
+                            Bounds.fromDOMRectList(context, createRange(node, offset, text.length).getClientRects())
+                        )
+                    );
+                } else {
+                    textBounds.push(new TextBounds(text, getRangeBounds(context, node, offset, text.length)));
+                }
             } else {
                 const replacementNode = node.splitText(text.length);
                 textBounds.push(new TextBounds(text, getWrapperBounds(context, node)));
@@ -58,10 +67,10 @@ const getWrapperBounds = (context: Context, node: Text): Bounds => {
         }
     }
 
-    return new Bounds(0, 0, 0, 0);
+    return Bounds.EMPTY;
 };
 
-const getRangeBounds = (context: Context, node: Text, offset: number, length: number): Bounds => {
+const createRange = (node: Text, offset: number, length: number): Range => {
     const ownerDocument = node.ownerDocument;
     if (!ownerDocument) {
         throw new Error('Node has no owner document');
@@ -69,7 +78,11 @@ const getRangeBounds = (context: Context, node: Text, offset: number, length: nu
     const range = ownerDocument.createRange();
     range.setStart(node, offset);
     range.setEnd(node, offset + length);
-    return Bounds.fromClientRect(context, range.getBoundingClientRect());
+    return range;
+};
+
+const getRangeBounds = (context: Context, node: Text, offset: number, length: number): Bounds => {
+    return Bounds.fromClientRect(context, createRange(node, offset, length).getBoundingClientRect());
 };
 
 const breakText = (value: string, styles: CSSParsedDeclaration): string[] => {