/**
* Given two strings, compute a score representing whether the internal
* boundary falls on logical boundaries.
* Scores range from 5 (best) to 0 (worst).
* @param one First CFStringRef.
* @param two Second CFStringRef.
* @return The score.
*/
CFIndex diff_cleanupSemanticScore(CFStringRef one, CFStringRef two) {
static Boolean firstRun = true;
static CFCharacterSetRef alphaNumericSet = NULL;
static CFCharacterSetRef whiteSpaceSet = NULL;
static CFCharacterSetRef controlSet = NULL;
static regex_t blankLineEndRegEx;
static regex_t blankLineStartRegEx;
if (firstRun) {
alphaNumericSet = CFCharacterSetGetPredefined(kCFCharacterSetAlphaNumeric);
whiteSpaceSet = CFCharacterSetGetPredefined(kCFCharacterSetWhitespaceAndNewline);
controlSet = CFCharacterSetGetPredefined(kCFCharacterSetControl);
int status;
status = regcomp(&blankLineEndRegEx, "\n\r?\n$", REG_EXTENDED | REG_NOSUB);
check(status == 0);
status = regcomp(&blankLineStartRegEx, "^\r?\n\r?\n", REG_EXTENDED | REG_NOSUB);
check(status == 0);
firstRun = false;
}
if (CFStringGetLength(one) == 0 || CFStringGetLength(two) == 0) {
// Edges are the best.
return 5;
}
// Each port of this function behaves slightly differently due to
// subtle differences in each language's definition of things like
// 'whitespace'. Since this function's purpose is largely cosmetic,
// the choice has been made to use each language's native features
// rather than force total conformity.
CFIndex score = 0;
UniChar lastCharOfStringOne = CFStringGetCharacterAtIndex(one, (CFStringGetLength(one) - 1));
UniChar firstCharOfStringTwo = CFStringGetCharacterAtIndex(two, 0);
// One point for non-alphanumeric.
if (!CFCharacterSetIsCharacterMember(alphaNumericSet, lastCharOfStringOne)
|| !CFCharacterSetIsCharacterMember(alphaNumericSet, firstCharOfStringTwo)) {
score++;
// Two points for whitespace.
if (CFCharacterSetIsCharacterMember(whiteSpaceSet, lastCharOfStringOne)
|| CFCharacterSetIsCharacterMember(whiteSpaceSet, firstCharOfStringTwo)) {
score++;
// Three points for line breaks.
if (CFCharacterSetIsCharacterMember(controlSet, lastCharOfStringOne)
|| CFCharacterSetIsCharacterMember(controlSet, firstCharOfStringTwo)) {
score++;
// Four points for blank lines.
if (diff_regExMatch(one, &blankLineEndRegEx)
|| diff_regExMatch(two, &blankLineStartRegEx)) {
score++;
}
}
}
}
return score;
}
/**
* Given two strings, compute a score representing whether the internal
* boundary falls on logical boundaries.
* Scores range from 6 (best) to 0 (worst).
* @param one First CFStringRef.
* @param two Second CFStringRef.
* @return The score.
*/
CFIndex diff_cleanupSemanticScore(CFStringRef one, CFStringRef two) {
static Boolean firstRun = true;
static CFCharacterSetRef alphaNumericSet = NULL;
static CFCharacterSetRef whiteSpaceSet = NULL;
static CFCharacterSetRef controlSet = NULL;
static regex_t blankLineEndRegEx;
static regex_t blankLineStartRegEx;
if (firstRun) {
alphaNumericSet = CFCharacterSetGetPredefined(kCFCharacterSetAlphaNumeric);
whiteSpaceSet = CFCharacterSetGetPredefined(kCFCharacterSetWhitespaceAndNewline);
controlSet = CFCharacterSetGetPredefined(kCFCharacterSetControl);
// Define some regex patterns for matching boundaries.
int status;
status = regcomp(&blankLineEndRegEx, "\n\r?\n$", REG_EXTENDED | REG_NOSUB);
check(status == 0);
status = regcomp(&blankLineStartRegEx, "^\r?\n\r?\n", REG_EXTENDED | REG_NOSUB);
check(status == 0);
firstRun = false;
}
if (CFStringGetLength(one) == 0 || CFStringGetLength(two) == 0) {
// Edges are the best.
return 6;
}
// Each port of this function behaves slightly differently due to
// subtle differences in each language's definition of things like
// 'whitespace'. Since this function's purpose is largely cosmetic,
// the choice has been made to use each language's native features
// rather than force total conformity.
UniChar char1 =
CFStringGetCharacterAtIndex(one, (CFStringGetLength(one) - 1));
UniChar char2 =
CFStringGetCharacterAtIndex(two, 0);
Boolean nonAlphaNumeric1 =
!CFCharacterSetIsCharacterMember(alphaNumericSet, char1);
Boolean nonAlphaNumeric2 =
!CFCharacterSetIsCharacterMember(alphaNumericSet, char2);
Boolean whitespace1 =
nonAlphaNumeric1 && CFCharacterSetIsCharacterMember(whiteSpaceSet, char1);
Boolean whitespace2 =
nonAlphaNumeric2 && CFCharacterSetIsCharacterMember(whiteSpaceSet, char2);
Boolean lineBreak1 =
whitespace1 && CFCharacterSetIsCharacterMember(controlSet, char1);
Boolean lineBreak2 =
whitespace2 && CFCharacterSetIsCharacterMember(controlSet, char2);
Boolean blankLine1 =
lineBreak1 && diff_regExMatch(one, &blankLineEndRegEx);
Boolean blankLine2 =
lineBreak2 && diff_regExMatch(two, &blankLineStartRegEx);
if (blankLine1 || blankLine2) {
// Five points for blank lines.
return 5;
} else if (lineBreak1 || lineBreak2) {
// Four points for line breaks.
return 4;
} else if (nonAlphaNumeric1 && !whitespace1 && whitespace2) {
// Three points for end of sentences.
return 3;
} else if (whitespace1 || whitespace2) {
// Two points for whitespace.
return 2;
} else if (nonAlphaNumeric1 || nonAlphaNumeric2) {
// One point for non-alphanumeric.
return 1;
}
return 0;
}
