1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/style/nsRuleWalker.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,105 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/*
1.10 + * a class that walks the lexicographic tree of rule nodes as style
1.11 + * rules are matched
1.12 + */
1.13 +
1.14 +#ifndef nsRuleWalker_h_
1.15 +#define nsRuleWalker_h_
1.16 +
1.17 +#include "nsRuleNode.h"
1.18 +#include "nsIStyleRule.h"
1.19 +#include "StyleRule.h"
1.20 +
1.21 +class nsRuleWalker {
1.22 +public:
1.23 + nsRuleNode* CurrentNode() { return mCurrent; }
1.24 + void SetCurrentNode(nsRuleNode* aNode) {
1.25 + NS_ASSERTION(aNode, "Must have node here!");
1.26 + mCurrent = aNode;
1.27 + }
1.28 +
1.29 +protected:
1.30 + void DoForward(nsIStyleRule* aRule) {
1.31 + mCurrent = mCurrent->Transition(aRule, mLevel, mImportance);
1.32 + NS_POSTCONDITION(mCurrent, "Transition messed up");
1.33 + }
1.34 +
1.35 +public:
1.36 + void Forward(nsIStyleRule* aRule) {
1.37 + NS_PRECONDITION(!nsRefPtr<mozilla::css::StyleRule>(do_QueryObject(aRule)),
1.38 + "Calling the wrong Forward() overload");
1.39 + DoForward(aRule);
1.40 + }
1.41 + void Forward(mozilla::css::StyleRule* aRule) {
1.42 + DoForward(aRule);
1.43 + mCheckForImportantRules =
1.44 + mCheckForImportantRules && !aRule->GetImportantRule();
1.45 + }
1.46 + // ForwardOnPossiblyCSSRule should only be used by callers that have
1.47 + // an explicit list of rules they need to walk, with the list
1.48 + // already containing any important rules they care about.
1.49 + void ForwardOnPossiblyCSSRule(nsIStyleRule* aRule) {
1.50 + DoForward(aRule);
1.51 + }
1.52 +
1.53 + void Reset() { mCurrent = mRoot; }
1.54 +
1.55 + bool AtRoot() { return mCurrent == mRoot; }
1.56 +
1.57 + void SetLevel(uint8_t aLevel, bool aImportance,
1.58 + bool aCheckForImportantRules) {
1.59 + NS_ASSERTION(!aCheckForImportantRules || !aImportance,
1.60 + "Shouldn't be checking for important rules while walking "
1.61 + "important rules");
1.62 + mLevel = aLevel;
1.63 + mImportance = aImportance;
1.64 + mCheckForImportantRules = aCheckForImportantRules;
1.65 + }
1.66 + uint8_t GetLevel() const { return mLevel; }
1.67 + bool GetImportance() const { return mImportance; }
1.68 + bool GetCheckForImportantRules() const { return mCheckForImportantRules; }
1.69 +
1.70 + bool AuthorStyleDisabled() const { return mAuthorStyleDisabled; }
1.71 +
1.72 + // We define the visited-relevant link to be the link that is the
1.73 + // nearest self-or-ancestor to the node being matched.
1.74 + enum VisitedHandlingType {
1.75 + // Do rule matching as though all links are unvisited.
1.76 + eRelevantLinkUnvisited,
1.77 + // Do rule matching as though the relevant link is visited and all
1.78 + // other links are unvisited.
1.79 + eRelevantLinkVisited,
1.80 + // Do rule matching as though a rule should match if it would match
1.81 + // given any set of visitedness states. (used by users other than
1.82 + // nsRuleWalker)
1.83 + eLinksVisitedOrUnvisited
1.84 + };
1.85 +
1.86 +private:
1.87 + nsRuleNode* mCurrent; // Our current position. Never null.
1.88 + nsRuleNode* mRoot; // The root of the tree we're walking.
1.89 + uint8_t mLevel; // an nsStyleSet::sheetType
1.90 + bool mImportance;
1.91 + bool mCheckForImportantRules; // If true, check for important rules as
1.92 + // we walk and set to false if we find
1.93 + // one.
1.94 + bool mAuthorStyleDisabled;
1.95 +
1.96 +public:
1.97 + nsRuleWalker(nsRuleNode* aRoot, bool aAuthorStyleDisabled)
1.98 + : mCurrent(aRoot)
1.99 + , mRoot(aRoot)
1.100 + , mAuthorStyleDisabled(aAuthorStyleDisabled)
1.101 + {
1.102 + NS_ASSERTION(mCurrent, "Caller screwed up and gave us null node");
1.103 + MOZ_COUNT_CTOR(nsRuleWalker);
1.104 + }
1.105 + ~nsRuleWalker() { MOZ_COUNT_DTOR(nsRuleWalker); }
1.106 +};
1.107 +
1.108 +#endif /* !defined(nsRuleWalker_h_) */
