Introduce Selection#compute{Left,Top} in assert_selection()

third_party/WebKit/LayoutTests/editing/assert_selection.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 'use strict';
 
 // This file provides |assert_selection(sample, tester, expectedText, options)|
 // assertion to W3C test harness to write editing test cases easier.
 //
 // |sample| is an HTML fragment text which is inserted as |innerHTML|. It should
@@ skipping 42 matching lines @@
 // TODO(yosin): Please use "clang-format -style=Chromium -i" for formatting
 // this file.
 
 (function() {
 /** @enum{string} */
 const DumpAs = {
   DOM_TREE: 'domtree',
   FLAT_TREE: 'flattree',
 };
 
+// Offset adjustment for mouse clicking used in |compute{Left,Top}()|.

[yoichio, 2017/06/30 01:45:59]

Why do you need this adjustment?

[yosin_UTC9, 2017/06/30 08:21:50]

This value should be 2. It is border-size comes from html.css as

iframe {
    border: 2px inset
}

+const kOffsetLeftAdjustment = 4;
+const kOffsetTopAdjustment = 4;
+
 /** @const @type {string} */
 const kTextArea = 'TEXTAREA';
 
 class Traversal {
   /**
    * @param {!Node} node
    * @return {Node}
    */
   firstChildOf(node) { throw new Error('You should implement firstChildOf'); }
 
@@ skipping 584 matching lines @@
   serializeInternal(node) {
     if (isElement(node))
       return this.handleElementNode(node);
     if (isCharacterData(node))
       return this.handleCharacterData(node);
     throw new Error(`Unexpected node ${node}`);
   }
 }
 
 /**
+ * @param {!HTMLElement} element
+ * @return {number}
+ */
+function computeLeft(element) {
+  let left = kOffsetLeftAdjustment + element.ownerDocument.offsetLeft;
+  for (let runner = element; runner; runner = runner.offsetParent)
+    left += runner.offsetLeft;
+  return left;
+}
+
+/**
+ * @param {!HTMLElement} element
+ * @return {number}
+ */
+function computeTop(element) {
+  let top = kOffsetTopAdjustment + element.ownerDocument.offsetTop;
+  for (let runner = element; runner; runner = runner.offsetParent)
+    top += runner.offsetTop;
+  return top;
+}
+
+/**
  * @this {!DOMSelection}
  * @param {string} html
  * @param {string=} opt_text
  */
 function setClipboardData(html, opt_text) {
   assert_not_equals(window.internals, undefined,
     'This test requests clipboard access from JavaScript.');
   function computeTextData() {
     if (opt_text !== undefined)
       return opt_text;
@@ skipping 28 matching lines @@
 
     // Set focus to sample IFRAME to make |eventSender| and
     // |testRunner.execCommand()| to work on sample rather than main frame.
     this.iframe_.focus();
     /** @const @type {!Selection} */
     this.selection_ = this.iframe_.contentWindow.getSelection();
     this.selection_.document = this.document_;
     this.selection_.document.offsetLeft = this.iframe_.offsetLeft;
     this.selection_.document.offsetTop = this.iframe_.offsetTop;
     this.selection_.setClipboardData = setClipboardData;
+    this.selection_.computeLeft = computeLeft;
+    this.selection_.computeTop = computeTop;
     this.load(sampleText);
   }
 
   /** @return {!HTMLDocument} */
   get document() { return this.document_; }
 
   /** @return {!Selection} */
   get selection() { return this.selection_; }
 
   /**
@@ skipping 205 matching lines @@
   throw new Error(`${description}\n` +
     `\t expected ${expectedText},\n` +
     `\t but got  ${actualText},\n` +
     `\t sameupto ${commonPrefixOf(expectedText, actualText)}`);
 }
 
 // Export symbols
 window.Sample = Sample;
 window.assert_selection = assertSelection;
 })();