Handling new frames and frame navigations with find-in-page during a find session.

third_party/WebKit/Source/web/TextFinder.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
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  * modification, are permitted provided that the following conditions are
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@@ skipping 182 matching lines @@
 
             if (m_activeMatchIndex + 1 > m_lastMatchCount)
                 m_activeMatchIndex = 0;
             else if (m_activeMatchIndex < 0)
                 m_activeMatchIndex = m_lastMatchCount - 1;
         }
         WebRect selectionRect = ownerFrame().frameView()->contentsToRootFrame(m_activeMatch->boundingBox());
         reportFindInPageSelection(selectionRect, m_activeMatchIndex + 1, identifier);
     }
 
+    m_lastFindRequestCompletedWithNoMatches = false;

[dcheng, 2016/09/21 07:15:44]

Ditto: what is the significance behind these two changes? I just don't have
enough of the find state machine in my head to understand the purpose.

[paulmeyer, 2016/09/21 15:40:52]

First change:

By this point in this function, at least one match has been found, so
|m_lastFindRequestCompletedWithNoMatches| should definitely be false. Without
this, there are some problems with TextFinder not searching certain frames when
it really should. I actually ended up already landing this one line change
separately in the mean time to fix these problems faster. This is no longer part
of this patch.

Second change:

I'm not sure if this is actually specifically needed for this patch, but the
active match should be reset if it is being cleared. I wrote this function
myself in a previous patch, and I think I just missed doing this, so I figured
I'd fix it. I could put this in a separate patch if you'd like though.

     return true;
 }
 
 void TextFinder::clearActiveFindMatch()
 {
     m_currentActiveMatchFrame = false;
     setMarkerActive(m_activeMatch.get(), false);
+    resetActiveMatch();
 }
 
 void TextFinder::stopFindingAndClearSelection()
 {
     cancelPendingScopingEffort();
 
     // Remove all markers for matches found and turn off the highlighting.
     ownerFrame().frame()->document()->markers().removeMarkers(DocumentMarker::TextMatch);
     ownerFrame().frame()->editor().setMarkedTextMatchesAreHighlighted(false);
     clearFindMatchesCache();
@@ skipping 57 matching lines @@
         // The view might be null on detached frames.
         LocalFrame* frame = ownerFrame().frame();
         if (frame && frame->page())
             m_frameScoping = true;
 
         // Now, defer scoping until later to allow find operation to finish quickly.
         scopeStringMatchesSoon(identifier, searchText, options, false); // false means just reset, so don't do it again.
         return;
     }
 
-    if (!shouldScopeMatches(searchText)) {
+    if (!shouldScopeMatches(searchText, options)) {
         finishCurrentScopingEffort(identifier);
         return;
     }
 
     PositionInFlatTree searchStart = PositionInFlatTree::firstPositionInNode(ownerFrame().frame()->document());
     PositionInFlatTree searchEnd = PositionInFlatTree::lastPositionInNode(ownerFrame().frame()->document());
     DCHECK_EQ(searchStart.document(), searchEnd.document());
 
     if (m_resumeScopingFromRange) {
         // This is a continuation of a scoping operation that timed out and didn't
@@ skipping 367 matching lines @@
     return ownerFrame().frame()->document()->markers().setMarkersActive(EphemeralRange(range), active);
 }
 
 void TextFinder::unmarkAllTextMatches()
 {
     LocalFrame* frame = ownerFrame().frame();
     if (frame && frame->page() && frame->editor().markedTextMatchesAreHighlighted())
         frame->document()->markers().removeMarkers(DocumentMarker::TextMatch);
 }
 
-bool TextFinder::shouldScopeMatches(const String& searchText)
+bool TextFinder::shouldScopeMatches(const String& searchText, const WebFindOptions& options)
 {
     // Don't scope if we can't find a frame or a view.
     // The user may have closed the tab/application, so abort.
     LocalFrame* frame = ownerFrame().frame();
-    if (!frame || !frame->view() || !frame->page() || !ownerFrame().hasVisibleContent())
+    if (!frame || !frame->view() || !frame->page())
         return false;
 
     DCHECK(frame->document());
     DCHECK(frame->view());
 
+    if (options.force)
+        return true;
+
+    if (!ownerFrame().hasVisibleContent())
+        return false;
+
     // If the frame completed the scoping operation and found 0 matches the last
     // time it was searched, then we don't have to search it again if the user is
     // just adding to the search string or sending the same search string again.
     if (m_lastFindRequestCompletedWithNoMatches && !m_lastSearchString.isEmpty()) {
         // Check to see if the search string prefixes match.
         String previousSearchPrefix =
             searchText.substring(0, m_lastSearchString.length());
 
         if (previousSearchPrefix == m_lastSearchString)
             return false; // Don't search this frame, it will be fruitless.
@@ skipping 43 matching lines @@
 DEFINE_TRACE(TextFinder)
 {
     visitor->trace(m_ownerFrame);
     visitor->trace(m_activeMatch);
     visitor->trace(m_resumeScopingFromRange);
     visitor->trace(m_deferredScopingWork);
     visitor->trace(m_findMatchesCache);
 }
 
 } // namespace blink