Implement full search for text directives for Scroll to Text Fragment…

… spec.

https://bugs.webkit.org/show_bug.cgi?id=243511
rdar://89301977

Reviewed by Ryosuke Niwa.

Add full search algorithm as specified in the spec here:
https://wicg.github.io/scroll-to-text-fragment/
To properly search for text fragments from the directives that we have
parsed out of the URL.

Currently these have been tested against some examples, but in the
near future we will import that WPT tests and ensure that all of those pass
as well as address the last few edge case FIXMEs left in this implementation.

Source/WebCore/dom/FragmentDirectiveParser.cpp:
Fix an error in parsing the fragment directive that wasn't caught until I
finished coding the search algorithm.

* Source/WebCore/dom/BoundaryPoint.h:
(WebCore::operator!=):
* Source/WebCore/dom/FragmentDirectiveParser.cpp:
(WebCore::FragmentDirectiveParser::parseFragmentDirective):
* Source/WebCore/dom/FragmentDirectiveRangeFinder.cpp:
(WebCore::FragmentDirectiveRangeFinder::isSearchInvisible):
(WebCore::FragmentDirectiveRangeFinder::isNonSearchableSubtree):
(WebCore::FragmentDirectiveRangeFinder::nearestBlockAncestor):
(WebCore::FragmentDirectiveRangeFinder::getBoundaryPointAtIndex):
(WebCore::FragmentDirectiveRangeFinder::indexIsWordBoundary):
(WebCore::FragmentDirectiveRangeFinder::isVisibleTextNode):
(WebCore::FragmentDirectiveRangeFinder::findRangeFromNodeList):
(WebCore::FragmentDirectiveRangeFinder::rangeOfStringInRange):
(WebCore::FragmentDirectiveRangeFinder::advanceRangeStartToNextNonWhitespace):
(WebCore::FragmentDirectiveRangeFinder::rangesForFragments):
(WebCore::FragmentDirectiveRangeFinder::rangeForFragment):
(WebCore::FragmentDirectiveRangeFinder::collapseIfRootsDiffer): Deleted.
(WebCore::FragmentDirectiveRangeFinder::rangeOfString): Deleted.
* Source/WebCore/dom/FragmentDirectiveRangeFinder.h:
* Source/WebCore/rendering/style/RenderStyle.h:
(WebCore::RenderStyle::isDisplayBlockLevel const):

Canonical link: https://commits.webkit.org/253383@main

Source/WebCore/dom/BoundaryPoint.h

@@ -68,6 +68,11 @@ inline bool operator==(const BoundaryPoint& a, const BoundaryPoint& b)
     return a.container.ptr() == b.container.ptr() && a.offset == b.offset;
 }
 
+inline bool operator!=(const BoundaryPoint& a, const BoundaryPoint& b)
+{
+    return !(a == b);
+}
+
 inline BoundaryPoint makeBoundaryPointBeforeNodeContents(Node& node)
 {
     return { node, 0 };

Source/WebCore/dom/FragmentDirectiveParser.cpp

@@ -63,6 +63,7 @@ FragmentDirectiveParser::FragmentDirectiveParser(const URL& url)
     m_isValid = true;
 }
 
+// https://wicg.github.io/scroll-to-text-fragment/#parse-a-text-directive
 void FragmentDirectiveParser::parseFragmentDirective(StringView fragmentDirective)
 {
     LOG_WITH_STREAM(TextFragment, stream << " parseFragmentDirective: ");
@@ -101,7 +102,7 @@ void FragmentDirectiveParser::parseFragmentDirective(StringView fragmentDirectiv
 
         if (tokens.first().endsWith('-') && tokens.first().length() > 1) {
             auto takenFirstToken = tokens.takeFirst();
-            if (auto prefix = WTF::URLParser::formURLDecode(StringView(takenFirstToken).left(takenFirstToken.length() - 2)))
+            if (auto prefix = WTF::URLParser::formURLDecode(StringView(takenFirstToken).left(takenFirstToken.length() - 1)))
                 parsedTextDirective.prefix = WTFMove(*prefix);
             else
                 LOG_WITH_STREAM(TextFragment, stream << " could not decode prefix ");