Move Mac to using renderer spellchecker.

chrome/browser/spellcheck_worditerator.cc

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/spellcheck_worditerator.h"
-
-#include <map>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/string_util.h"
-#include "chrome/browser/spellchecker.h"
-
-#include "third_party/icu/public/common/unicode/normlzr.h"
-#include "third_party/icu/public/common/unicode/schriter.h"
-#include "third_party/icu/public/common/unicode/uchar.h"
-#include "third_party/icu/public/common/unicode/uscript.h"
-#include "third_party/icu/public/common/unicode/uset.h"
-#include "third_party/icu/public/i18n/unicode/ulocdata.h"
-
-SpellcheckCharAttribute::SpellcheckCharAttribute() {
-  InitializeScriptTable();
-
-  // Even though many dictionaries treats numbers and contractions as words and
-  // treats USCRIPT_COMMON characters as word characters, the
-  // SpellcheckWordIterator class treats USCRIPT_COMMON characters as non-word
-  // characters to strictly-distinguish contraction characters from word
-  // characters.
-  SetWordScript(USCRIPT_COMMON, false);
-
-  // Initialize the table of characters used for contractions.
-  // This array consists of the 'Midletter' and 'MidNumLet' characters of the
-  // word-break property list provided by Unicode, Inc.:
-  //   http://www.unicode.org/Public/UNIDATA/auxiliary/WordBreakProperty.txt
-  static const UChar32 kMidLetters[] = {
-      L'\x003A',  // MidLetter # COLON
-      L'\x00B7',  // MidLetter # MIDDLE DOT
-      L'\x0387',  // MidLetter # GREEK ANO TELEIA
-      L'\x05F4',  // MidLetter # HEBREW PUNCTUATION GERSHAYIM
-      L'\x2027',  // MidLetter # HYPHENATION POINT
-      L'\xFE13',  // MidLetter # PRESENTATION FORM FOR VERTICAL COLON
-      L'\xFE55',  // MidLetter # SMALL COLON
-      L'\xFF1A',  // MidLetter # FULLWIDTH COLON
-      L'\x0027',  // MidNumLet # APOSTROPHE
-      L'\x002E',  // MidNumLet # FULL STOP
-      L'\x2018',  // MidNumLet # LEFT SINGLE QUOTATION MARK
-      L'\x2019',  // MidNumLet # RIGHT SINGLE QUOTATION MARK
-      L'\x2024',  // MidNumLet # ONE DOT LEADER
-      L'\xFE52',  // MidNumLet # SMALL FULL STOP
-      L'\xFF07',  // MidNumLet # FULLWIDTH APOSTROPHE
-      L'\xFF0E',  // MidNumLet # FULLWIDTH FULL STOP
-  };
-  for (size_t i = 0; i < arraysize(kMidLetters); ++i)
-    middle_letters_[kMidLetters[i]] = true;
-}
-
-SpellcheckCharAttribute::~SpellcheckCharAttribute() {
-}
-
-// Sets the default language for this object.
-// This function retrieves the exemplar set to set up the default character
-// attributes.
-void SpellcheckCharAttribute::SetDefaultLanguage(const std::string& language) {
-  UErrorCode status = U_ZERO_ERROR;
-  ULocaleData* locale_data = ulocdata_open(language.c_str(), &status);
-  if (U_FAILURE(status))
-    return;
-
-  // Retrieves the exemplar set of the given language and update the
-  // character-attribute table to treat its characters as word characters.
-  USet* exemplar_set = uset_open(1, 0);
-  ulocdata_getExemplarSet(locale_data, exemplar_set, 0, ULOCDATA_ES_STANDARD,
-                          &status);
-  ulocdata_close(locale_data);
-  if (U_SUCCESS(status)) {
-    int length = uset_size(exemplar_set);
-    for (int i = 0; i < length; ++i) {
-      UChar32 character = uset_charAt(exemplar_set, i);
-      SetWordScript(GetScriptCode(character), true);
-    }
-
-    // Many languages use combining characters to input their characters from
-    // keyboards. On the other hand, this exemplar set does not always include
-    // combining characters for such languages.
-    // To treat such combining characters as word characters, we decompose
-    // this exemplar set and treat the decomposed characters as word characters.
-    icu::UnicodeString composed;
-    for (int i = 0; i < length; ++i)
-      composed.append(uset_charAt(exemplar_set, i));
-
-    icu::UnicodeString decomposed;
-    icu::Normalizer::decompose(composed, FALSE, 0, decomposed, status);
-    if (U_SUCCESS(status)) {
-      icu::StringCharacterIterator iterator(decomposed);
-      UChar32 character = iterator.first32();
-      while (character != icu::CharacterIterator::DONE) {
-        SetWordScript(GetScriptCode(character), true);
-        character = iterator.next32();
-      }
-    }
-  }
-  uset_close(exemplar_set);
-}
-
-// Returns whether or not the given character is a character used by the
-// selected dictionary.
-bool SpellcheckCharAttribute::IsWordChar(UChar32 character) const {
-  return IsWordScript(GetScriptCode(character)) && !u_isdigit(character);
-}
-
-// Returns whether or not the given character is a character used by
-// contractions.
-bool SpellcheckCharAttribute::IsContractionChar(UChar32 character) const {
-  std::map<UChar32, bool>::const_iterator iterator;
-  iterator = middle_letters_.find(character);
-  if (iterator == middle_letters_.end())
-    return false;
-  return iterator->second;
-}
-
-// Initializes the mapping table.
-void SpellcheckCharAttribute::InitializeScriptTable() {
-  for (size_t i = 0; i < arraysize(script_attributes_); ++i)
-    script_attributes_[i] = false;
-}
-
-// Retrieves the ICU script code.
-UScriptCode SpellcheckCharAttribute::GetScriptCode(UChar32 character) const {
-  UErrorCode status = U_ZERO_ERROR;
-  UScriptCode script_code = uscript_getScript(character, &status);
-  return U_SUCCESS(status) ? script_code : USCRIPT_INVALID_CODE;
-}
-
-// Updates the mapping table from an ICU script code to its attribute, i.e.
-// whether not a script is used by the selected dictionary.
-void SpellcheckCharAttribute::SetWordScript(const int script_code,
-                                            bool in_use) {
-  if (script_code < 0 ||
-      static_cast<size_t>(script_code) >= arraysize(script_attributes_))
-    return;
-  script_attributes_[script_code] = in_use;
-}
-
-// Returns whether or not the given script is used by the selected
-// dictionary.
-bool SpellcheckCharAttribute::IsWordScript(
-    const UScriptCode script_code) const {
-  if (script_code < 0 ||
-      static_cast<size_t>(script_code) >= arraysize(script_attributes_))
-    return false;
-  return script_attributes_[script_code];
-}
-
-SpellcheckWordIterator::SpellcheckWordIterator()
-    : word_(NULL),
-      length_(0),
-      position_(0),
-      allow_contraction_(false),
-      attribute_(NULL) {
-}
-
-SpellcheckWordIterator::~SpellcheckWordIterator() {
-}
-
-// Initialize a word-iterator object.
-void SpellcheckWordIterator::Initialize(
-    const SpellcheckCharAttribute* attribute,
-    const char16* word,
-    size_t length,
-    bool allow_contraction) {
-  word_ = word;
-  position_ = 0;
-  length_ = static_cast<int>(length);
-  allow_contraction_ = allow_contraction;
-  attribute_ = attribute;
-}
-
-// Retrieves a word (or a contraction).
-// When a contraction is enclosed with contraction characters (e.g. 'isn't',
-// 'rock'n'roll'), we should discard the beginning and the end of the
-// contraction but we should never split the contraction.
-// To handle this case easily, we should firstly extract a segment consisting
-// of word characters and contraction characters, and discard contraction
-// characters at the beginning and the end of the extracted segment.
-bool SpellcheckWordIterator::GetNextWord(string16* word_string,
-                                         int* word_start,
-                                         int* word_length) {
-  word_string->clear();
-  *word_start = 0;
-  *word_length = 0;
-  while (position_ < length_) {
-    int segment_start = 0;
-    int segment_end = 0;
-    GetSegment(&segment_start, &segment_end);
-    TrimSegment(segment_start, segment_end, word_start, word_length);
-    if (*word_length > 0)
-      return Normalize(*word_start, *word_length, word_string);
-  }
-
-  return false;
-}
-
-// Retrieves a segment consisting of word characters (and contraction
-// characters if the |allow_contraction_| value is true).
-// When the current position refers to a non-word character, this function
-// returns a non-empty segment consisting of the character itself. In this
-// case, the TrimSegment() function discards the character and returns an
-// empty word (i.e. |word_length| == 0).
-void SpellcheckWordIterator::GetSegment(int* segment_start,
-                                        int* segment_end) {
-  int position = position_;
-  while (position <  length_) {
-    UChar32 character;
-    U16_NEXT(word_, position, length_, character);
-    if (!attribute_->IsWordChar(character)) {
-      if (!allow_contraction_ || !attribute_->IsContractionChar(character))
-        break;
-    }
-  }
-  *segment_start = position_;
-  *segment_end = position;
-  position_ = position;
-}
-
-// Discards non-word characters at the beginning and the end of the given
-// segment.
-void SpellcheckWordIterator::TrimSegment(int segment_start,
-                                         int segment_end,
-                                         int* word_start,
-                                         int* word_length) const {
-  while (segment_start < segment_end) {
-    UChar32 character;
-    int segment_next = segment_start;
-    U16_NEXT(word_, segment_next, segment_end, character);
-    if (attribute_->IsWordChar(character)) {
-      *word_start = segment_start;
-      break;
-    }
-    segment_start = segment_next;
-  }
-  while (segment_end >= segment_start) {
-    UChar32 character;
-    int segment_prev = segment_end;
-    U16_PREV(word_, segment_start, segment_prev, character);
-    if (attribute_->IsWordChar(character)) {
-      *word_length = segment_end - segment_start;
-      break;
-    }
-    segment_end = segment_prev;
-  }
-}
-
-// Normalizes a non-terminated string into its canonical form so that
-// a spellchecker object can check spellings of words which contain ligatures,
-// full-width letters, etc.
-// USCRIPT_LATIN does not only consists of US-ASCII and ISO/IEC 8859-1, but
-// also consists of ISO/IEC 8859-{2,3,4,9,10}, ligatures, fullwidth latin,
-// etc. For its details, please read the script table in
-// "http://www.unicode.org/Public/UNIDATA/Scripts.txt".
-bool SpellcheckWordIterator::Normalize(int input_start,
-                                       int input_length,
-                                       string16* output_string) const {
-  // Unicode Standard Annex #15 "http://www.unicode.org/unicode/reports/tr15/"
-  // does not only write NFKD and NFKC can compose ligatures into their ASCII
-  // alternatives, but also write NFKC keeps accents of characters.
-  // Therefore, NFKC seems to be the best option for hunspell.
-  icu::UnicodeString input(FALSE, &word_[input_start], input_length);
-  UErrorCode status = U_ZERO_ERROR;
-  icu::UnicodeString output;
-  icu::Normalizer::normalize(input, UNORM_NFKC, 0, output, status);
-  if (U_SUCCESS(status))
-    output_string->assign(output.getTerminatedBuffer());
-  return status == U_ZERO_ERROR || status == U_STRING_NOT_TERMINATED_WARNING;
-}