Make SurroundingText work for a Range.

It generalize the algorithm to find the surrounding text to be able to
work with a starting position and an ending position. The goal is to be
able to get the surrounding text arround the current selection.

BUG=330238

Review URL: https://codereview.chromium.org/323983006

git-svn-id: svn://svn.chromium.org/blink/trunk@176015 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/editing/SurroundingText.cpp

@@ -39,26 +39,42 @@
 
 namespace WebCore {
 
+SurroundingText::SurroundingText(const Range& range, unsigned maxLength)
+    : m_startOffsetInContent(0)
+    , m_endOffsetInContent(0)
+{
+    initialize(range.startPosition(), range.endPosition(), maxLength);
+}
+
 SurroundingText::SurroundingText(const Position& position, unsigned maxLength)
-    : m_positionOffsetInContent(0)
+    : m_startOffsetInContent(0)
+    , m_endOffsetInContent(0)
+{
+    initialize(position, position, maxLength);
+}
+
+void SurroundingText::initialize(const Position& startPosition, const Position& endPosition, unsigned maxLength)
 {
+    ASSERT(startPosition.document() == endPosition.document());
+
     const unsigned halfMaxLength = maxLength / 2;
 
-    Document* document = position.document();
-    // The |position| will have no document if it is null (as in no position).
+    Document* document = startPosition.document();
+    // The position will have no document if it is null (as in no position).
     if (!document)
         return;
 
     // The forward range starts at the selection end and ends at the document's
     // end. It will then be updated to only contain the text in the text in the
     // right range around the selection.
-    RefPtrWillBeRawPtr<Range> forwardRange = Range::create(*document, position, lastPositionInNode(document->documentElement()).parentAnchoredEquivalent());
+    RefPtrWillBeRawPtr<Range> forwardRange = Range::create(*document, endPosition, lastPositionInNode(document->documentElement()).parentAnchoredEquivalent());
     CharacterIterator forwardIterator(forwardRange.get(), TextIteratorStopsOnFormControls);
+    // FIXME: why do we stop going trough the text if we were not able to select something on the right?
     if (!forwardIterator.atEnd())
         forwardIterator.advance(maxLength - halfMaxLength);
 
     forwardRange = forwardIterator.range();
-    if (!forwardRange || !Range::create(*document, position, forwardRange->startPosition())->text().length()) {
+    if (!forwardRange || !Range::create(*document, endPosition, forwardRange->startPosition())->text().length()) {
         ASSERT(forwardRange);
         return;
     }
@@ -66,7 +82,7 @@ SurroundingText::SurroundingText(const Position& position, unsigned maxLength)
     // Same as with the forward range but with the backward range. The range
     // starts at the document's start and ends at the selection start and will
     // be updated.
-    RefPtrWillBeRawPtr<Range> backwardsRange = Range::create(*document, firstPositionInNode(document->documentElement()).parentAnchoredEquivalent(), position);
+    RefPtrWillBeRawPtr<Range> backwardsRange = Range::create(*document, firstPositionInNode(document->documentElement()).parentAnchoredEquivalent(), startPosition);
     BackwardsCharacterIterator backwardsIterator(backwardsRange.get(), TextIteratorStopsOnFormControls);
     if (!backwardsIterator.atEnd())
         backwardsIterator.advance(halfMaxLength);
@@ -77,7 +93,8 @@ SurroundingText::SurroundingText(const Position& position, unsigned maxLength)
         return;
     }
 
-    m_positionOffsetInContent = Range::create(*document, backwardsRange->endPosition(), position)->text().length();
+    m_startOffsetInContent = Range::create(*document, backwardsRange->endPosition(), startPosition)->text().length();
+    m_endOffsetInContent = Range::create(*document, backwardsRange->endPosition(), endPosition)->text().length();
     m_contentRange = Range::create(*document, backwardsRange->endPosition(), forwardRange->startPosition());
     ASSERT(m_contentRange);
 }
@@ -112,9 +129,14 @@ String SurroundingText::content() const
     return String();
 }
 
-unsigned SurroundingText::positionOffsetInContent() const
+unsigned SurroundingText::startOffsetInContent() const
+{
+    return m_startOffsetInContent;
+}
+
+unsigned SurroundingText::endOffsetInContent() const
 {
-    return m_positionOffsetInContent;
+    return m_endOffsetInContent;
 }
 
 } // namespace WebCore

third_party/WebKit/Source/core/editing/SurroundingText.h

@@ -42,16 +42,21 @@ class Range;
 class SurroundingText {
     WTF_MAKE_NONCOPYABLE(SurroundingText);
 public:
+    SurroundingText(const Range&, unsigned maxLength);
     SurroundingText(const Position&, unsigned maxLength);
 
     String content() const;
-    unsigned positionOffsetInContent() const;
+    unsigned startOffsetInContent() const;
+    unsigned endOffsetInContent() const;
 
     PassRefPtrWillBeRawPtr<Range> rangeFromContentOffsets(unsigned startOffsetInContent, unsigned endOffsetInContent);
 
 private:
+    void initialize(const Position&, const Position&, unsigned maxLength);
+
     RefPtrWillBePersistent<Range> m_contentRange;
-    size_t m_positionOffsetInContent;
+    size_t m_startOffsetInContent;
+    size_t m_endOffsetInContent;
 };
 
 } // namespace WebCore

third_party/WebKit/Source/core/editing/SurroundingTextTest.cpp

@@ -58,7 +58,8 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
         SurroundingText surroundingText(selection.start(), 1);
 
         EXPECT_EQ("f", surroundingText.content());
-        EXPECT_EQ(0u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -67,7 +68,8 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
 
         // maxlength/2 is used on the left and right.
         EXPECT_EQ("foo", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(1u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -75,7 +77,8 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
         SurroundingText surroundingText(selection.start(), 42);
 
         EXPECT_EQ("foo bar", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(1u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -85,7 +88,8 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
         SurroundingText surroundingText(selection.start(), 42);
 
         EXPECT_EQ(0u, surroundingText.content().length());
-        EXPECT_EQ(0u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -93,7 +97,8 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
         SurroundingText surroundingText(selection.start(), 2);
 
         EXPECT_EQ("ar", surroundingText.content());
-        EXPECT_EQ(1u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -101,7 +106,58 @@ TEST_F(SurroundingTextTest, BasicCaretSelection)
         SurroundingText surroundingText(selection.start(), 42);
 
         EXPECT_EQ("foo bar", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(7u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(7u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(7u, surroundingText.endOffsetInContent());
+    }
+}
+
+TEST_F(SurroundingTextTest, BasicRangeSelection)
+{
+    setHTML(String("<p id='selection'>Lorem ipsum dolor sit amet</p>"));
+
+    {
+        VisibleSelection selection = select(0, 5);
+        SurroundingText surroundingText(*selection.firstRange(), 1);
+
+        EXPECT_EQ("Lorem ", surroundingText.content());
+        EXPECT_EQ(0u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(5u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(0, 5);
+        SurroundingText surroundingText(*selection.firstRange(), 5);
+
+        EXPECT_EQ("Lorem ip", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(6u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(0, 5);
+        SurroundingText surroundingText(*selection.firstRange(), 42);
+
+        EXPECT_EQ("Lorem ipsum dolor sit amet", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(6u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(6, 11);
+        SurroundingText surroundingText(*selection.firstRange(), 2);
+
+        EXPECT_EQ(" ipsum ", surroundingText.content());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(6u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(6, 11);
+        SurroundingText surroundingText(*selection.firstRange(), 42);
+
+        EXPECT_EQ("Lorem ipsum dolor sit amet", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(7u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(12u, surroundingText.endOffsetInContent());
     }
 }
 
@@ -114,7 +170,8 @@ TEST_F(SurroundingTextTest, TreeCaretSelection)
         SurroundingText surroundingText(selection.start(), 1);
 
         EXPECT_EQ("f", surroundingText.content());
-        EXPECT_EQ(0u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(0u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -122,7 +179,8 @@ TEST_F(SurroundingTextTest, TreeCaretSelection)
         SurroundingText surroundingText(selection.start(), 5);
 
         EXPECT_EQ("foo", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(1u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -130,7 +188,8 @@ TEST_F(SurroundingTextTest, TreeCaretSelection)
         SurroundingText surroundingText(selection.start(), 1337);
 
         EXPECT_EQ("This is outside of foo bar the selected node", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(20u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(20u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(20u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -138,7 +197,8 @@ TEST_F(SurroundingTextTest, TreeCaretSelection)
         SurroundingText surroundingText(selection.start(), 2);
 
         EXPECT_EQ("ar", surroundingText.content());
-        EXPECT_EQ(1u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
     }
 
     {
@@ -146,7 +206,58 @@ TEST_F(SurroundingTextTest, TreeCaretSelection)
         SurroundingText surroundingText(selection.start(), 1337);
 
         EXPECT_EQ("This is outside of foo bar the selected node", surroundingText.content().simplifyWhiteSpace());
-        EXPECT_EQ(26u, surroundingText.positionOffsetInContent());
+        EXPECT_EQ(26u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(26u, surroundingText.endOffsetInContent());
+    }
+}
+
+TEST_F(SurroundingTextTest, TreeRangeSelection)
+{
+    setHTML(String("<div>This is outside of <p id='selection'>foo bar</p> the selected node</div>"));
+
+    {
+        VisibleSelection selection = select(0, 1);
+        SurroundingText surroundingText(*selection.firstRange(), 1);
+
+        EXPECT_EQ("fo", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(0u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(1u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(0, 3);
+        SurroundingText surroundingText(*selection.firstRange(), 12);
+
+        EXPECT_EQ("e of foo bar", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(5u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(8u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(0, 3);
+        SurroundingText surroundingText(*selection.firstRange(), 1337);
+
+        EXPECT_EQ("This is outside of foo bar the selected node", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(20u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(23u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(4, 7);
+        SurroundingText surroundingText(*selection.firstRange(), 12);
+
+        EXPECT_EQ("foo bar the se", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(5u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(8u, surroundingText.endOffsetInContent());
+    }
+
+    {
+        VisibleSelection selection = select(0, 7);
+        SurroundingText surroundingText(*selection.firstRange(), 1337);
+
+        EXPECT_EQ("This is outside of foo bar the selected node", surroundingText.content().simplifyWhiteSpace());
+        EXPECT_EQ(20u, surroundingText.startOffsetInContent());
+        EXPECT_EQ(27u, surroundingText.endOffsetInContent());
     }
 }
 

third_party/WebKit/Source/web/WebSurroundingText.cpp

@@ -55,7 +55,8 @@ WebString WebSurroundingText::textContent() const
 
 size_t WebSurroundingText::hitOffsetInTextContent() const
 {
-    return m_private->positionOffsetInContent();
+    ASSERT(m_private->startOffsetInContent() == m_private->endOffsetInContent());
+    return m_private->startOffsetInContent();
 }
 
 WebRange WebSurroundingText::rangeFromContentOffsets(size_t startOffsetInContent, size_t endOffsetInContent)