public static FilePosition between(FilePosition a, FilePosition b) {
return instance(
a.source(),
a.endLineNo(),
a.endCharInFile(),
a.endCharInLine(),
b.startLineNo(),
b.startCharInFile(),
b.startCharInLine());
}
void processToken(String text) {
TokenClassification tClass = TokenClassification.classify(text);
if (tClass == null) {
return;
}
switch (tClass) {
case LINEBREAK:
// Allow external code to force line-breaks.
// This allows us to create a composite-renderer that renders
// original source code next to translated source code.
emit("\n");
return;
case SPACE:
pendingSpace = true;
return;
case COMMENT:
if (mark != null && lastLine != mark.startLineNo()) {
newline();
lastLine = mark.startLineNo();
} else if ("/".equals(lastToken) || pendingSpace) {
space();
}
pendingSpace = false;
emit(text);
if (text.startsWith("//")) {
newline();
pendingSpace = false;
} else {
pendingSpace = true;
}
return;
default:
break;
}
boolean spaceBefore = pendingSpace;
pendingSpace = false;
boolean spaceAfter = false;
// Determine which pairs of tokens cannot be adjacent and put a space
// between them.
if (tClass == lastClass) {
// Adjacent punctuation, strings, and words require space.
// Numbers and words are both of type OTHER.
// This decision may be revisited in the following to prevent
// excessive space inside parentheses.
spaceBefore = !"(".equals(lastToken);
} else if (lastClass == TokenClassification.REGEX) {
if (tClass == TokenClassification.OTHER || "/".equals(text)) {
// Make sure words don't run into regex flags, and that / operator
// does not combine with end of regex to make a line comment.
spaceBefore = true;
}
} else if (tClass == TokenClassification.REGEX && "/".equals(lastToken)) {
// Allowing these two tokens to run together could introduce a line
// comment.
spaceBefore = true;
} else if (tClass == TokenClassification.OTHER
&& Character.isDigit(text.charAt(0))
&& ".".equals(lastToken)) {
// Following a dot operator with a number is illegal syntactically, but
// this renderer should not allow any lexical confusion.
spaceBefore = true;
}
if (tClass == TokenClassification.OTHER) {
if ("}".equals(lastToken)) {
spaceBefore = true;
}
if (isKeyword(text.toString())) {
// Put a space between if and other keywords and the parenthesis.
spaceAfter = true;
}
}
// If this token is an open bracket, we want to indent, but not before
// writing the token to avoid over-indenting the open bracket.
if (text.length() == 1) {
char ch0 = text.charAt(0);
switch (ch0) {
case '{':
if (lastClass == TokenClassification.PUNCTUATION) {
if (":".equals(lastToken)) { // See JSON test.
spaceBefore = true;
} else if (!(")".equals(lastToken) || "=".equals(lastToken))) {
// If starting a block following a parenthesized condition, or
// an object literal assigned.
spaceBefore = !("(".equals(lastToken) || "[".equals(lastToken));
}
}
spaceAfter = true;
break;
case '[':
if (")".equals(lastToken)) {
spaceBefore = false;
}
spaceAfter = true;
break;
case '(':
if (")".equals(lastToken)) { // Calling a parenthesized value.
spaceBefore = false;
}
break;
case '}':
spaceBefore = !"{".equals(lastToken);
spaceAfter = true;
break;
case ')':
spaceBefore = false;
spaceAfter = true;
break;
case ']':
spaceBefore = !"}".equals(lastToken);
spaceAfter = true;
break;
case ',':
spaceBefore = false;
spaceAfter = true;
break;
case ';':
spaceBefore = false;
spaceAfter = true;
break;
case ':':
spaceBefore = ":".equals(lastToken); // Since :: is a token in ES4
spaceAfter = true;
break;
case '=':
spaceBefore = true;
spaceAfter = true;
break;
case '.':
spaceBefore =
lastToken != null
&& (TokenClassification.isNumber(lastToken) || ".".equals(lastToken));
spaceAfter = false;
break;
}
}
// Write any whitespace before the token.
if (spaceBefore) {
space();
}
// Actually write the token.
emit(text);
pendingSpace = spaceAfter;
lastClass = tClass;
lastToken = text;
if (mark != null) {
lastLine = mark.startLineNo();
}
}