https://bugs.webkit.org/show_bug.cgi?id=229218
Reviewed by Devin Rousso.
Source/WebCore:
Test: inspector/css/getMatchedStylesForNodeLargeSelectors.html
CSS rules are limited to 8192 selector components in WebCore, and when more components are present the rule is
split into multiple `StyleRule` instances. This meant Web Inspector could not reliably resolve a `StyleRule`
back to its source data, which we do to enable things like editing, as well as to make sure we show the un-split
selector in the Styles sidebar of the Elements tab. Previously, the presences of multiple `StyleRule`s for a
single source data declaration was not accounted for, which meant that rules after the split rules would show a
mix of style information from the actual rule as well as a rule some number of declarations later in the same
style sheet. This is resolved by marking `StyleRule`s that have been split and marking the last of the split
rules. This allows us to then forgo incrementing the index for looking up raw declarations until we encounter
the last rule from a split `StyleRule`.
* css/StyleRule.cpp:
(WebCore::StyleRule::StyleRule):
(WebCore::StyleRule::createForSplitting):
(WebCore::StyleRule::splitIntoMultipleRulesWithMaximumSelectorComponentCount const):
* css/StyleRule.h:
- Added two members to track rules that are split into multiple rules due to exceeding the 8192 component limit
for selectors in order to determine later which rules are effectively duplicates of each other. We use two
members here, one to track that the rule was split from a larger authored rule (`m_isSplitRule`), and one to
mark the last rule split from a given rule (`m_isLastRuleInSplitRule`). The second member prevents situations
where we might otherwise accidentally continue iterating into a list of `StyleRule` where two large authored
rules that had to be split are present next to each other in an ordered collection of `StyleRule`.
* inspector/InspectorStyleSheet.cpp:
(WebCore::selectorsFromSource):
- Use a vector of `CSSSelector`s for specificity information since we now collect selectors from potentially
multiple `CSSStyleRule`s.
(WebCore::InspectorStyleSheet::cssStyleRulesSplitFromSameRule):
- Find any neighboring CSSStyleRules that were split from the same original rule based on the order of rules as
well as the new flags in `StyleRule`
(WebCore::InspectorStyleSheet::selectorsForCSSStyleRule):
- Find all selectors for a given CSSStyleRule, including other `CSSStyleRule`s split from the same rule in a
style sheet.
(WebCore::InspectorStyleSheet::buildObjectForSelectorList):
- Use all CSSSelectors from for the CSSStyleRule and other rules that were split from the same rule in a style
sheet.
(WebCore::InspectorStyleSheet::ruleSourceDataFor const):
(WebCore::InspectorStyleSheet::ruleIndexByStyle const):
- When looking up an index to get rule source data, make sure we don't overcount split rules.
* inspector/InspectorStyleSheet.h:
LayoutTests:
Test very large (8192 individual component) selectors to ensure surrounding styles are correctly resolved.
* inspector/css/getMatchedStylesForNodeLargeSelectors-expected.txt: Added.
* inspector/css/getMatchedStylesForNodeLargeSelectors.html: Added.
Canonical link: https://commits.webkit.org/240769@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@281354 268f45cc-cd09-0410-ab3c-d52691b4dbfc
8e9b7a21d6