in pontoon/base/static/js/lib/diff.js [855:900]
function diff_cleanupSemanticScore_(one, two) {
if (!one || !two) {
// 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.
var char1 = one.charAt(one.length - 1);
var char2 = two.charAt(0);
var nonAlphaNumeric1 = char1.match(diff_match_patch.nonAlphaNumericRegex_);
var nonAlphaNumeric2 = char2.match(diff_match_patch.nonAlphaNumericRegex_);
var whitespace1 = nonAlphaNumeric1 &&
char1.match(diff_match_patch.whitespaceRegex_);
var whitespace2 = nonAlphaNumeric2 &&
char2.match(diff_match_patch.whitespaceRegex_);
var lineBreak1 = whitespace1 &&
char1.match(diff_match_patch.linebreakRegex_);
var lineBreak2 = whitespace2 &&
char2.match(diff_match_patch.linebreakRegex_);
var blankLine1 = lineBreak1 &&
one.match(diff_match_patch.blanklineEndRegex_);
var blankLine2 = lineBreak2 &&
two.match(diff_match_patch.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;
}