1/*
2 * Copyright (C) 2013, 2016 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "StyleChange.h"
28
29#include "RenderStyle.h"
30
31namespace WebCore {
32namespace Style {
33
34Change determineChange(const RenderStyle& s1, const RenderStyle& s2)
35{
36 if (s1.display() != s2.display())
37 return Detach;
38 if (s1.hasPseudoStyle(PseudoId::FirstLetter) != s2.hasPseudoStyle(PseudoId::FirstLetter))
39 return Detach;
40 // We just detach if a renderer acquires or loses a column-span, since spanning elements
41 // typically won't contain much content.
42 if (s1.columnSpan() != s2.columnSpan())
43 return Detach;
44 if (!s1.contentDataEquivalent(&s2))
45 return Detach;
46 // When text-combine property has been changed, we need to prepare a separate renderer object.
47 // When text-combine is on, we use RenderCombineText, otherwise RenderText.
48 // https://bugs.webkit.org/show_bug.cgi?id=55069
49 if (s1.hasTextCombine() != s2.hasTextCombine())
50 return Detach;
51
52 if (s1 != s2) {
53 if (s1.inheritedNotEqual(&s2))
54 return Inherit;
55
56 if (s1.alignItems() != s2.alignItems() || s1.justifyItems() != s2.justifyItems())
57 return Inherit;
58
59 return NoInherit;
60 }
61
62 // If the pseudoStyles have changed, we want any StyleChange that is not NoChange
63 // because setStyle will do the right thing with anything else.
64 if (s1.hasAnyPublicPseudoStyles()) {
65 for (PseudoId pseudoId = PseudoId::FirstPublicPseudoId; pseudoId < PseudoId::FirstInternalPseudoId; pseudoId = static_cast<PseudoId>(static_cast<unsigned>(pseudoId) + 1)) {
66 if (s1.hasPseudoStyle(pseudoId)) {
67 RenderStyle* ps2 = s2.getCachedPseudoStyle(pseudoId);
68 if (!ps2)
69 return NoInherit;
70 RenderStyle* ps1 = s1.getCachedPseudoStyle(pseudoId);
71 if (!ps1 || *ps1 != *ps2)
72 return NoInherit;
73 }
74 }
75 }
76
77 return NoChange;
78}
79
80}
81}
82