Revert removal of grammar checking and marking code

third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp

Index: third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp
diff --git a/third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp b/third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp
index b0e55b7e7e62695cf380d3db75fb31947120cd34..7ba54bf4aacd1a37851e81d99304929ca4abce93 100644
--- a/third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp
+++ b/third_party/WebKit/Source/core/editing/spellcheck/TextCheckingHelper.cpp
@@ -41,6 +41,34 @@
 
 namespace blink {
 
+static void findBadGrammars(TextCheckerClient& client, const UChar* text, int start, int length, Vector<TextCheckingResult>& results)
+{
+    int checkLocation = start;
+    int checkLength = length;
+
+    while (0 < checkLength) {
+        int badGrammarLocation = -1;
+        int badGrammarLength = 0;
+        Vector<GrammarDetail> badGrammarDetails;
+        client.checkGrammarOfString(String(text + checkLocation, checkLength), badGrammarDetails, &badGrammarLocation, &badGrammarLength);
+        if (!badGrammarLength)
+            break;
+        DCHECK_LE(0, badGrammarLocation);
+        DCHECK_LE(badGrammarLocation, checkLength);
+        DCHECK_LT(0, badGrammarLength);
+        DCHECK_LE(badGrammarLocation + badGrammarLength, checkLength);
+        TextCheckingResult badGrammar;
+        badGrammar.decoration = TextDecorationTypeGrammar;
+        badGrammar.location = checkLocation + badGrammarLocation;
+        badGrammar.length = badGrammarLength;
+        badGrammar.details.swap(badGrammarDetails);
+        results.append(badGrammar);
+
+        checkLocation += (badGrammarLocation + badGrammarLength);
+        checkLength -= (badGrammarLocation + badGrammarLength);
+    }
+}
+
 static void findMisspellings(TextCheckerClient& client, const UChar* text, int start, int length, Vector<TextCheckingResult>& results)
 {
     TextBreakIterator* iterator = wordBreakIterator(text + start, length);
@@ -286,6 +314,222 @@ String TextCheckingHelper::findFirstMisspelling(int& firstMisspellingOffset, boo
     return firstMisspelling;
 }
 
+String TextCheckingHelper::findFirstMisspellingOrBadGrammar(bool& outIsSpelling, int& outFirstFoundOffset, GrammarDetail& outGrammarDetail)
+{
+    if (!unifiedTextCheckerEnabled())
+        return "";
+
+    String firstFoundItem;
+    String misspelledWord;
+    String badGrammarPhrase;
+
+    // Initialize out parameters; these will be updated if we find something to return.
+    outIsSpelling = true;
+    outFirstFoundOffset = 0;
+    outGrammarDetail.location = -1;
+    outGrammarDetail.length = 0;
+    outGrammarDetail.guesses.clear();
+    outGrammarDetail.userDescription = "";
+
+    // Expand the search range to encompass entire paragraphs, since text checking needs that much context.
+    // Determine the character offset from the start of the paragraph to the start of the original search range,
+    // since we will want to ignore results in this area.
+    Position paragraphStart = startOfParagraph(createVisiblePosition(m_start)).toParentAnchoredPosition();
+    Position paragraphEnd = m_end;
+    int totalRangeLength = TextIterator::rangeLength(paragraphStart, paragraphEnd);
+    paragraphEnd = endOfParagraph(createVisiblePosition(m_start)).toParentAnchoredPosition();
+
+    int rangeStartOffset = TextIterator::rangeLength(paragraphStart, m_start);
+    int totalLengthProcessed = 0;
+
+    bool firstIteration = true;
+    bool lastIteration = false;
+    while (totalLengthProcessed < totalRangeLength) {
+        // Iterate through the search range by paragraphs, checking each one for spelling and grammar.
+        int currentLength = TextIterator::rangeLength(paragraphStart, paragraphEnd);
+        int currentStartOffset = firstIteration ? rangeStartOffset : 0;
+        int currentEndOffset = currentLength;
+        if (inSameParagraph(createVisiblePosition(paragraphStart), createVisiblePosition(m_end))) {
+            // Determine the character offset from the end of the original search range to the end of the paragraph,
+            // since we will want to ignore results in this area.
+            currentEndOffset = TextIterator::rangeLength(paragraphStart, m_end);
+            lastIteration = true;
+        }
+        if (currentStartOffset < currentEndOffset) {
+            String paragraphString = plainText(EphemeralRange(paragraphStart, paragraphEnd));
+            if (paragraphString.length() > 0) {
+                bool foundGrammar = false;
+                int spellingLocation = 0;
+                int grammarPhraseLocation = 0;
+                int grammarDetailLocation = 0;
+                unsigned grammarDetailIndex = 0;
+
+                Vector<TextCheckingResult> results;
+                TextCheckingTypeMask checkingTypes = TextCheckingTypeSpelling | TextCheckingTypeGrammar;
+                checkTextOfParagraph(m_client->textChecker(), paragraphString, checkingTypes, results);
+
+                for (unsigned i = 0; i < results.size(); i++) {
+                    const TextCheckingResult* result = &results[i];
+                    if (result->decoration == TextDecorationTypeSpelling && result->location >= currentStartOffset && result->location + result->length <= currentEndOffset) {
+                        DCHECK_GT(result->length, 0);
+                        DCHECK_GE(result->location, 0);
+                        spellingLocation = result->location;
+                        misspelledWord = paragraphString.substring(result->location, result->length);
+                        DCHECK(misspelledWord.length());
+                        break;
+                    }
+                    if (result->decoration == TextDecorationTypeGrammar && result->location < currentEndOffset && result->location + result->length > currentStartOffset) {
+                        DCHECK_GT(result->length, 0);
+                        DCHECK_GE(result->location, 0);
+                        // We can't stop after the first grammar result, since there might still be a spelling result after
+                        // it begins but before the first detail in it, but we can stop if we find a second grammar result.
+                        if (foundGrammar)
+                            break;
+                        for (unsigned j = 0; j < result->details.size(); j++) {
+                            const GrammarDetail* detail = &result->details[j];
+                            DCHECK_GT(detail->length, 0);
+                            DCHECK_GE(detail->location, 0);
+                            if (result->location + detail->location >= currentStartOffset && result->location + detail->location + detail->length <= currentEndOffset && (!foundGrammar || result->location + detail->location < grammarDetailLocation)) {
+                                grammarDetailIndex = j;
+                                grammarDetailLocation = result->location + detail->location;
+                                foundGrammar = true;
+                            }
+                        }
+                        if (foundGrammar) {
+                            grammarPhraseLocation = result->location;
+                            outGrammarDetail = result->details[grammarDetailIndex];
+                            badGrammarPhrase = paragraphString.substring(result->location, result->length);
+                            DCHECK(badGrammarPhrase.length());
+                        }
+                    }
+                }
+
+                if (!misspelledWord.isEmpty() && (badGrammarPhrase.isEmpty() || spellingLocation <= grammarDetailLocation)) {
+                    int spellingOffset = spellingLocation - currentStartOffset;
+                    if (!firstIteration)
+                        spellingOffset += TextIterator::rangeLength(m_start, paragraphStart);
+                    outIsSpelling = true;
+                    outFirstFoundOffset = spellingOffset;
+                    firstFoundItem = misspelledWord;
+                    break;
+                }
+                if (!badGrammarPhrase.isEmpty()) {
+                    int grammarPhraseOffset = grammarPhraseLocation - currentStartOffset;
+                    if (!firstIteration)
+                        grammarPhraseOffset += TextIterator::rangeLength(m_start, paragraphStart);
+                    outIsSpelling = false;
+                    outFirstFoundOffset = grammarPhraseOffset;
+                    firstFoundItem = badGrammarPhrase;
+                    break;
+                }
+            }
+        }
+        if (lastIteration || totalLengthProcessed + currentLength >= totalRangeLength)
+            break;
+        VisiblePosition newParagraphStart = startOfNextParagraph(createVisiblePosition(paragraphEnd));
+        paragraphStart = newParagraphStart.toParentAnchoredPosition();
+        paragraphEnd = endOfParagraph(newParagraphStart).toParentAnchoredPosition();
+        firstIteration = false;
+        totalLengthProcessed += currentLength;
+    }
+    return firstFoundItem;
+}
+
+int TextCheckingHelper::findFirstGrammarDetail(const Vector<GrammarDetail>& grammarDetails, int badGrammarPhraseLocation, int startOffset, int endOffset, bool markAll) const
+{
+    // Found some bad grammar. Find the earliest detail range that starts in our search range (if any).
+    // Optionally add a DocumentMarker for each detail in the range.
+    int earliestDetailLocationSoFar = -1;
+    int earliestDetailIndex = -1;
+    for (unsigned i = 0; i < grammarDetails.size(); i++) {
+        const GrammarDetail* detail = &grammarDetails[i];
+        DCHECK_GT(detail->length, 0);
+        DCHECK_GE(detail->location, 0);
+
+        int detailStartOffsetInParagraph = badGrammarPhraseLocation + detail->location;
+
+        // Skip this detail if it starts before the original search range
+        if (detailStartOffsetInParagraph < startOffset)
+            continue;
+
+        // Skip this detail if it starts after the original search range
+        if (detailStartOffsetInParagraph >= endOffset)
+            continue;
+
+        if (markAll) {
+            const EphemeralRange badGrammarRange = calculateCharacterSubrange(EphemeralRange(m_start, m_end), badGrammarPhraseLocation - startOffset + detail->location, detail->length);
+            badGrammarRange.document().markers().addMarker(badGrammarRange.startPosition(), badGrammarRange.endPosition(), DocumentMarker::Grammar, detail->userDescription);
+        }
+
+        // Remember this detail only if it's earlier than our current candidate (the details aren't in a guaranteed order)
+        if (earliestDetailIndex < 0 || earliestDetailLocationSoFar > detail->location) {
+            earliestDetailIndex = i;
+            earliestDetailLocationSoFar = detail->location;
+        }
+    }
+
+    return earliestDetailIndex;
+}
+
+String TextCheckingHelper::findFirstBadGrammar(GrammarDetail& outGrammarDetail, int& outGrammarPhraseOffset, bool markAll)
+{
+    // Initialize out parameters; these will be updated if we find something to return.
+    outGrammarDetail.location = -1;
+    outGrammarDetail.length = 0;
+    outGrammarDetail.guesses.clear();
+    outGrammarDetail.userDescription = "";
+    outGrammarPhraseOffset = 0;
+
+    String firstBadGrammarPhrase;
+
+    // Expand the search range to encompass entire paragraphs, since grammar checking needs that much context.
+    // Determine the character offset from the start of the paragraph to the start of the original search range,
+    // since we will want to ignore results in this area.
+    TextCheckingParagraph paragraph(EphemeralRange(m_start, m_end));
+
+    // Start checking from beginning of paragraph, but skip past results that occur before the start of the original search range.
+    int startOffset = 0;
+    while (startOffset < paragraph.checkingEnd()) {
+        Vector<GrammarDetail> grammarDetails;
+        int badGrammarPhraseLocation = -1;
+        int badGrammarPhraseLength = 0;
+        m_client->textChecker().checkGrammarOfString(paragraph.textSubstring(startOffset), grammarDetails, &badGrammarPhraseLocation, &badGrammarPhraseLength);
+
+        if (!badGrammarPhraseLength) {
+            DCHECK_EQ(badGrammarPhraseLocation, -1);
+            return String();
+        }
+
+        DCHECK_GE(badGrammarPhraseLocation, 0);
+        badGrammarPhraseLocation += startOffset;
+
+
+        // Found some bad grammar. Find the earliest detail range that starts in our search range (if any).
+        int badGrammarIndex = findFirstGrammarDetail(grammarDetails, badGrammarPhraseLocation, paragraph.checkingStart(), paragraph.checkingEnd(), markAll);
+        if (badGrammarIndex >= 0) {
+            DCHECK_LT(static_cast<unsigned>(badGrammarIndex), grammarDetails.size());
+            outGrammarDetail = grammarDetails[badGrammarIndex];
+        }
+
+        // If we found a detail in range, then we have found the first bad phrase (unless we found one earlier but
+        // kept going so we could mark all instances).
+        if (badGrammarIndex >= 0 && firstBadGrammarPhrase.isEmpty()) {
+            outGrammarPhraseOffset = badGrammarPhraseLocation - paragraph.checkingStart();
+            firstBadGrammarPhrase = paragraph.textSubstring(badGrammarPhraseLocation, badGrammarPhraseLength);
+
+            // Found one. We're done now, unless we're marking each instance.
+            if (!markAll)
+                break;
+        }
+
+        // These results were all between the start of the paragraph and the start of the search range; look
+        // beyond this phrase.
+        startOffset = badGrammarPhraseLocation + badGrammarPhraseLength;
+    }
+
+    return firstBadGrammarPhrase;
+}
+
 bool TextCheckingHelper::markAllMisspellings()
 {
     // Use the "markAll" feature of findFirstMisspelling. Ignore the return value and the "out parameter";
@@ -294,6 +538,15 @@ bool TextCheckingHelper::markAllMisspellings()
     return findFirstMisspelling(ignoredOffset, true).isEmpty();
 }
 
+void TextCheckingHelper::markAllBadGrammar()
+{
+    // Use the "markAll" feature of findFirstBadGrammar. Ignore the return value and "out parameters"; all we need to
+    // do is mark every instance.
+    GrammarDetail ignoredGrammarDetail;
+    int ignoredOffset;
+    findFirstBadGrammar(ignoredGrammarDetail, ignoredOffset, true);
+}
+
 bool TextCheckingHelper::unifiedTextCheckerEnabled() const
 {
     DCHECK(m_start.isNotNull());
@@ -311,8 +564,27 @@ void checkTextOfParagraph(TextCheckerClient& client, const String& text, TextChe
     if (checkingTypes & TextCheckingTypeSpelling)
         findMisspellings(client, characters.data(), 0, length, spellingResult);
 
-    if (spellingResult.size())
-        results.swap(spellingResult);
+    Vector<TextCheckingResult> grammarResult;
+    if (checkingTypes & TextCheckingTypeGrammar) {
+        // Only checks grammartical error before the first misspellings
+        int grammarCheckLength = length;
+        for (const auto& spelling : spellingResult) {
+            if (spelling.location < grammarCheckLength)
+                grammarCheckLength = spelling.location;
+        }
+
+        findBadGrammars(client, characters.data(), 0, grammarCheckLength, grammarResult);
+    }
+
+    if (grammarResult.size())
+        results.swap(grammarResult);
+
+    if (spellingResult.size()) {
+        if (results.isEmpty())
+            results.swap(spellingResult);
+        else
+            results.appendVector(spellingResult);
+    }
 }
 
 bool unifiedTextCheckerEnabled(const LocalFrame* frame)