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1360/*! literalizer
v0.4.0-a (c) Kyle Simpson
MIT License: http://getify.mit-license.org
*/
(function UMD(name,context,definition) {
if (typeof module != "undefined" && module.exports) module.exports = definition();
else if (typeof define == "function" && define.amd) define(definition);
else context[name] = definition(name,context);
})("LIT",this,function definition(name,context) {
"use strict";
function clone(obj) {
return JSON.parse(JSON.stringify(obj));
}
function combineGeneralSegments(segmentsSlice) {
var start, end, i, j;
for (i=0; i<segmentsSlice.length; i++) {
if (segmentsSlice[i].type === SEGMENT_GENERAL) {
start = end = i;
for (j=start+1; j<segmentsSlice.length; j++) {
end = j;
if (segmentsSlice[j].type !== SEGMENT_GENERAL) {
end = j-1;
break;
}
}
if (end > start) {
for (j=start+1; j<=end; j++) {
segmentsSlice[start].val += segmentsSlice[j].val;
}
segmentsSlice.splice(start+1,end-start);
}
else i = j;
}
}
return segmentsSlice;
}
// test for non-empty, non-whitespace, non-comment token
function isUsefulToken(tok) {
if (
!tok.val ||
// new-line?
(
tok.type === TOKEN_SPECIAL &&
/^(?:\r?\n)+$/.test(tok.val)
) ||
// whitespace?
(
tok.type === SEGMENT_GENERAL &&
/^\s*$/.test(tok.val)
) ||
// comment?
tok.type === SEGMENT_COMMENT
) {
return false;
}
else {
return true;
}
}
function lex(code) {
function saveText(text) {
// can we add to a previous general segment?
if (segments.length > 0 &&
segments[segments.length-1].type === SEGMENT_GENERAL
) {
segments[segments.length-1].val += text;
}
// otherwise, just create a new one
else {
segments.push({
type: SEGMENT_GENERAL,
val: text
});
}
}
// find previous useful token
function findUsefulToken(tokIdx) {
while (
tokIdx >= 0 &&
!isUsefulToken(tokens[tokIdx])
) {
tokIdx--;
}
// did we find one?
if (tokIdx >= 0) {
return tokIdx;
}
else {
return false;
}
}
// Algorithm here comes (partly) from pseudo-code description at:
// https://github.com/mozilla/sweet.js/wiki/design
function regexLookback() {
// try to find a balanced ( ) pair
function findParenPair(tokIdx) {
var i, tok, paren_count = 0;
for (i=tokIdx; i>=0; i--) {
tok = tokens[i];
// skip over non-useful tokens
if (!isUsefulToken(tok)) {
continue;
}
// special-token to consider?
if (tok.type === TOKEN_SPECIAL) {
if (tok.val === ")") {
paren_count++;
}
else if (tok.val === "(") {
paren_count--;
if (paren_count === 0) {
return i;
}
// parens unbalanced? abort!
else if (paren_count < 0) {
return false;
}
}
}
// parens not yet found?
else if (paren_count === 0) {
// abort!
return false;
}
}
// if we get here, we didn't find a balanced ( ) pair
return false;
}
// try to find a balanced { } pair
function findBracePair(tokIdx) {
var i, tok, brace_count = 0;
for (i=tokIdx; i>=0; i--) {
tok = tokens[i];
// skip over non-useful tokens
if (!isUsefulToken(tok)) {
continue;
}
// special-token to consider?
if (tok.type === TOKEN_SPECIAL) {
if (tok.val === "}") {
brace_count++;
}
else if (tok.val === "{") {
brace_count--;
if (brace_count === 0) {
return i;
}
// braces unbalanced? abort!
else if (brace_count < 0) {
return false;
}
}
}
// braces not yet found?
else if (brace_count === 0) {
// abort!
return false;
}
}
// if we get here, we didn't find a balanced { } pair
return false;
}
var tok_idx, i, tmp, tok;
// look for most recent useful token
tok_idx = findUsefulToken(tokens.length-1);
// nothing useful found?
if (tok_idx === false) {
// assume a valid regex literal
return true;
}
tok = tokens[tok_idx];
// preceding token is valid before a regex literal?
if (tok.type === TOKEN_SPECIAL) {
// is preceeding special-token a ')'?
if (tok.val === ")") {
tok_idx = findParenPair(tok_idx);
// did we find a balanced ( ) pair?
if (tok_idx !== false) {
// let's now look for a preceding if/while/for/with keyword
for (i=tok_idx-1; i>=0; i--) {
tok = tokens[i];
// skip over non-useful tokens
if (!isUsefulToken(tok)) {
continue;
}
// special-token to consider?
if (tok.type === TOKEN_SPECIAL) {
// preceding if/while/for/with keyword implies
// a valid regex literal
if (/^(?:if|while|for|with)$/.test(tok.val)) {
return true;
}
// otherwise, NOT a valid regex literal
else {
return false;
}
}
// otherwise, NOT a valid regex literal
else {
return false;
}
}
}
// otherwise, NOT a valid regex literal
else {
return false;
}
}
// is preceeding special-token a '}'?
else if (tok.val === "}") {
tok_idx = findBracePair(tok_idx);
// did we find a balanced { } pair?
if (tok_idx !== false) {
// is the { } pair a statement block?
if (tokens[tok_idx].is_block) {
// let's look at the previous (useful) token
tok_idx = findUsefulToken(tok_idx-1);
// nothing useful found preceding?
if (tok_idx === false) {
// NOTE: we found a { } statement block already
return true;
}
tok = tokens[tok_idx];
if (tok.type === TOKEN_SPECIAL) {
// ES6 fat-arrow function?
if (tok.val === "=>") {
// arrow functions are always function expressions,
// and regex literals can't immediately follow those
return false;
}
// look for normal function signature?
else {
tok_idx = findParenPair(tok_idx);
// balanced ( ) pair not found?
if (tok_idx === false) {
// NOTE: we found a { } statement block already,
// so subsequent regex literal allowed
return true;
}
// look backward to try and find a "function" keyword
tok_idx = findUsefulToken(tok_idx-1);
// nothing useful found preceding?
if (tok_idx === false) {
// NOTE: we found a { } statement block already,
// so subsequent regex literal allowed
return true;
}
// account for function name, if any
if (tokens[tok_idx].type === SEGMENT_GENERAL) {
// skipping the name, see if we can find
// the "function" keyword?
tok_idx = findUsefulToken(tok_idx-1);
// nothing useful found preceding?
if (tok_idx === false) {
// NOTE: we found a { } statement block already,
// so subsequent regex literal allowed
return true;
}
}
if (
// preceding is not a `function` keyword?
!/function(?:\s*\*)?/.test(tokens[tok_idx].val) ||
// preceding `function` is a declaration?
tokens[tok_idx].is_decl
) {
// NOTE: we found a { } statement block already,
// so subsequent regex literal allowed
return true;
}
// otherwise, subsequent regex literal not allowed
else {
return false;
}
}
}
else {
// NOTE: we found a { } statement block already,
// so subsequent regex literal allowed
return true;
}
}
// otherwise, the { } pair is a value, so subsequent
// regex literal not allowed
else {
return false;
}
}
// otherwise, no balanced { } pair found
else {
// NOTE: unbalanced { } is an invalid case, but we're
// erring on the side caution and assuming the }
// was the end of a statement block, not a value
return true;
}
}
// is preceeding special-token a keyword or punctuator/operator that implies rval?
else if (/^(?:new|return|throw|delete|in|else|void|typeof|yield|case|debugger|break|continue|(?:=>|[+\-*\/=~!%&,\|;:\?<>\(\{\[]))$/.test(tok.val)) {
return true;
}
// otherwise, NOT a valid regex literal
else {
return false;
}
}
// otherwise, NOT a valid regex literal
else {
return false;
}
}
function checkAbandonPropertyFunctionCandidate(matched) {
var tmp;
if (
// empty value token?
!matched ||
// whitespace only?
/^\s+$/.test(matched) ||
// not currently processing a property-function candidate anyway?
block_allowed[block_allowed.length-1].type !== BLOCK_ALLOWED_PROPERTY_FUNCTION
) {
// don't abandon anything :)
return;
}
if (
// unbalanced ( ) pairs?
block_allowed[block_allowed.length-1].paren_count < 0 ||
// unbalanced { } pairs?
block_allowed[block_allowed.length-1].brace_count < 0 ||
(
// expecting the opening { for the outer { } balanced pair?
block_allowed[block_allowed.length-1].brace_count === 0 &&
// but didn't find what was expected?
matched !== "{"
)
) {
// abandon as not actually a valid property-function
tmp = block_allowed.pop();
// update paren and brace counts after state pop, if need-be
if (tmp.paren_count > 0) {
if (block_allowed[block_allowed.length-1].paren_count === null) {
block_allowed[block_allowed.length-1].paren_count = tmp.paren_count;
}
else if (typeof block_allowed[block_allowed.length-1].paren_count === "number") {
block_allowed[block_allowed.length-1].paren_count += tmp.paren_count;
}
}
if (tmp.brace_count > 0) {
if (block_allowed[block_allowed.length-1].brace_count === null) {
block_allowed[block_allowed.length-1].brace_count = tmp.brace_count;
}
else if (typeof block_allowed[block_allowed.length-1].brace_count === "number") {
block_allowed[block_allowed.length-1].brace_count += tmp.brace_count;
}
}
}
}
// rules come from: http://javascript.spec.whatwg.org/#comment-syntax
function specialHTMLCommentMarker(text) {
var i;
if (text === "<!--") return true;
if (text === "-->") {
if (tokens.length > 0) {
// look backward to the beginning of the current line
for (i=tokens.length-1; i>=0; i--) {
// stop once we pass the beginning of the line
if (/\r?\n/.test(tokens[i].val)) {
break;
}
if (!(
// whitespace?
/^\s*$/.test(tokens[i].val) ||
// multi-line comment?
tokens[i].type === SEGMENT_COMMENT
)) {
// not a valid single-line comment marker
return false;
}
}
}
return true;
}
}
function processGeneral() {
var segmentsSlice, left_context, tok_idx,
prev_tok_idx, i,
preceding_dot_operator = false
;
// capture preceeding unmatched string, if any
if (unmatched) {
saveText(unmatched);
tokens.push({
type: SEGMENT_GENERAL,
val: unmatched
});
// valid identifier (and optional surrounding whitespace)?
if (/^\s*[^0-9\s\(\)\[\]\{\}<>,.:;=~+\-\*\/!%&\|\?\"\'][^\s\(\)\[\]\{\}<>,.:;=~+\-\*\/!%&\|\?\"\']*\s*$/.test(unmatched)) {
// if block is allowed and an identifier is found,
// it's a block-label candidate
statement_block_label_candidate = block_allowed[block_allowed.length-1].allowed;
// if a block is not allowed but an identifier is found,
// it's a property-function candidate, as long as it's not
// the name identifier of an existing function definition
property_function_candidate = (
!block_allowed[block_allowed.length-1].allowed &&
!(
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FUNCTION &&
block_allowed[block_allowed.length-1].paren_count === null
) &&
!(
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_ARROW_FUNCTION &&
block_allowed[block_allowed.length-1].brace_count === null
)
);
}
// valid identifier not found where necessary for block label
else {
statement_block_label_candidate = false;
}
}
// record whether there's a preceding . operator (not part of a number literal)
prev_tok_idx = findUsefulToken(tokens.length-1);
if (prev_tok_idx !== false &&
tokens[prev_tok_idx].type !== SEGMENT_NUMBER_LITERAL
) {
preceding_dot_operator = /\.\s*$/.test(tokens[prev_tok_idx].val);
}
// do we need to implicitly end an arrow-function or for-loop block-state
// processing because no outer { } balanced pair is going to be found?
if (
(
(
// currently processing an arrow-function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_ARROW_FUNCTION &&
// expecting the opening { for the outer { } balanced pair?
block_allowed[block_allowed.length-1].brace_count === null
) ||
(
// currently processing a for-loop?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FOR &&
// expecting the opening { for the outer { } balanced pair?
block_allowed[block_allowed.length-1].paren_count === 0
)
) &&
(
// non-whitespace/newline followed?
/[^\s]/.test(unmatched) ||
// non-comment, non { character followed?
!/\/\/|\/\*|[\{]/.test(match[0])
)
) {
block_allowed.pop();
}
if (match) {
left_context = code.slice(0,next_match_idx - match[0].length);
// starting a comment segment?
if (
match[0] === "//" ||
match[0] === "/*" ||
match[0] === "<!--" ||
match[0] === "-->"
) {
if (
// doesn't look like one of the special HTML-style
// comment markers?
!(
match[0] === "<!--" ||
match[0] === "-->"
) ||
// recognizable as HTML-style comment markers
(
!public_api.opts.overlook_html_comment_markers &&
specialHTMLCommentMarker(match[0])
)
) {
segments.push({
type: SEGMENT_COMMENT,
val: match[0]
});
tokens.push(clone(segments[segments.length-1]));
if (match[0] === "/*") {
lexing_state = STATE_MULTI_LINE_COMMENT;
}
else {
lexing_state = STATE_SINGLE_LINE_COMMENT;
}
}
// otherwise, is a `<!--` or `-->` sequence, but we cannot treat
// it as an HTML-style comment marker, so we should treat as
// separate operators instead
else {
saveText(match[0]);
for (i=0; i<match[0].length; i++) {
tokens.push({
type: TOKEN_SPECIAL,
val: match[0].charAt(i)
});
}
// the end character of either operator sequence (either - or >)
// is a disqualifier for subsequent statement block (see below too)
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed[block_allowed.length-1].allowed = false;
}
}
// starting a backtick-literal segment?
else if (match[0] === "`") {
segments.push({
type: SEGMENT_BACKTICK_LITERAL,
val: match[0]
});
tokens.push(clone(segments[segments.length-1]));
lexing_state = STATE_BACKTICK_LITERAL;
checkAbandonPropertyFunctionCandidate(match[0]);
}
// starting a string-literal segment?
else if (match[0] === "\"" || match[0] === "'") {
segments.push({
type: SEGMENT_STRING_LITERAL,
val: match[0],
raw: match[0]
});
tokens.push(clone(segments[segments.length-1]));
lexing_state = STATE_STRING_LITERAL;
STATE_PATTERNS[STATE_STRING_LITERAL] = new RegExp(match[0] + "|\r?\n","g");
checkAbandonPropertyFunctionCandidate(match[0]);
}
// number literal candidate?
else if (/^(?:(?:0[xX][0-9a-fA-F]+)|(?:0[oO][0-7]+)|(?:0[bB][01]+)|(?:\d+\.\d*(?:[eE][+-]?\d+)?)|(?:\.\d+(?:[eE][+-]?\d+)?)|(?:\d+(?:[eE][+-]?\d+)?))$/.test(match[0])) {
// number appears separate from an identifier?
if (!/[^\s\(\)\[\]\{\}<>,.:;=~+\-\*\/!%&\|\?\"\']$/.test(left_context)) {
segments.push({
type: SEGMENT_NUMBER_LITERAL,
val: match[0]
});
tokens.push(clone(segments[segments.length-1]));
statement_block_label_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
}
// otherwise, skip over, not a valid number literal to consider
else {
saveText(match[0]);
if (tokens[tokens.length-1].type === SEGMENT_GENERAL) {
tokens[tokens.length-1].val += match[0];
}
else {
tokens.push({
type: SEGMENT_GENERAL,
val: match[0]
});
}
switch_clause_candidate = false;
}
block_asi_allowed = true;
}
// what looks like a special keyword but is just a property
// identifier (because of preceding . operator)?
else if (preceding_dot_operator &&
/\w/.test(match[0])
) {
saveText(match[0]);
tokens.push({
type: SEGMENT_GENERAL,
val: match[0]
});
block_asi_allowed = true;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
}
// simple literal?
else if (/^(?:true|false|null|Infinity|NaN|undefined)$/.test(match[0])) {
segments.push({
type: SEGMENT_SIMPLE_LITERAL,
val: match[0]
});
tokens.push(clone(segments[segments.length-1]));
block_asi_allowed = true;
statement_block_label_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
}
// special token?
else if (/^(?:\b(?:new|return|throw|delete|in|of|else|void|typeof|yield|if|do|while|for|with|case|default|debugger|break|continue)\b|\bfunction(?:\s*\*)?|=>|[+\-*=~!%&,\|;:\?<>\(\)\{\}\[\]]|(?:\r?\n)+)$/.test(match[0])) {
saveText(match[0]);
tokens.push({
type: TOKEN_SPECIAL,
val: match[0]
});
// normal function?
if (/function(?:\s*\*)?/.test(match[0])) {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
// NOTE: wherever a statement block can appear,
// a function declaration can appear, and only there.
tokens[tokens.length-1].is_decl = block_allowed[block_allowed.length-1].allowed;
block_allowed.push({
type: BLOCK_ALLOWED_FUNCTION,
allowed: false,
paren_count: null,
brace_count: null
});
}
// arrow function?
else if (match[0] === "=>") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed.push({
type: BLOCK_ALLOWED_ARROW_FUNCTION,
allowed: false,
brace_count: null
});
}
// starting a for-loop?
else if (match[0] === "for") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed.push({
type: BLOCK_ALLOWED_FOR,
allowed: false,
paren_count: null
});
}
// `new` operator?
else if (match[0] === "new") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed[block_allowed.length-1].allowed = false;
}
// switch clauses?
else if (/case|default/.test(match[0])) {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = true;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
}
// new-line?
else if (/^(?:\r?\n)+$/.test(match[0])) {
// check block ASI at this new-line
if (block_asi_allowed) {
block_allowed[block_allowed.length-1].allowed = true;
block_asi_allowed = false;
}
}
// opening ( parenthesis?
else if (match[0] === "(") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
// are we continuing a property-function candidate with an outer ( ) pair?
if (property_function_candidate) {
property_function_candidate = false;
block_allowed.push({
type: BLOCK_ALLOWED_PROPERTY_FUNCTION,
allowed: false,
paren_count: 1,
brace_count: null
});
}
else if (
// processing a for-loop currently?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FOR ||
(
(
// processing a normal function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FUNCTION ||
// processing a property-function candidate currently?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_PROPERTY_FUNCTION
) &&
// still haven't found its outer ( ) balanced pair?
block_allowed[block_allowed.length-1].brace_count === null
)
) {
// expecting the opening ( of the outer ( ) balanced pair?
if (block_allowed[block_allowed.length-1].paren_count === null) {
block_allowed[block_allowed.length-1].paren_count = 1;
}
// otherwise, keep count to find outer ( ) balanced pair
else {
block_allowed[block_allowed.length-1].paren_count++;
}
}
// otherwise, just a non-special ( operator
else {
block_allowed[block_allowed.length-1].allowed = false;
}
}
// closing ) parenthesis?
else if (match[0] === ")") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
if (
(
// processing a for-loop currently?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FOR ||
(
(
// processing a property-function candidate currently?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_PROPERTY_FUNCTION ||
// processing a normal function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FUNCTION
) &&
// still haven't found its outer ( ) balanced pair?
block_allowed[block_allowed.length-1].brace_count === null
)
) &&
// already found the opening ( of the outer ( ) balanced pair?
block_allowed[block_allowed.length-1].paren_count !== null
) {
block_allowed[block_allowed.length-1].paren_count--;
// found the closing ) for the outer ( ) balanced pair?
if (block_allowed[block_allowed.length-1].paren_count === 0) {
block_allowed[block_allowed.length-1].allowed = true;
// now look for the outer { } balanced pair
block_allowed[block_allowed.length-1].brace_count = 0;
}
else {
checkAbandonPropertyFunctionCandidate(match[0]);
}
}
// otherwise, just a non-special ) operator
else {
block_asi_allowed = true;
}
}
// opening { brace?
else if (match[0] === "{") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
if (
// general block-allowed processing state?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_GENERAL ||
(
(
// processing normal function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FUNCTION ||
// processing arrow-function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_ARROW_FUNCTION ||
// processing property-function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_PROPERTY_FUNCTION
) &&
// function body-block has started already?
block_allowed[block_allowed.length-1].brace_count !== null
)
) {
// if a block is allowed here, the { starts a block
tokens[tokens.length-1].is_block = block_allowed[block_allowed.length-1].allowed;
if ("brace_count" in block_allowed[block_allowed.length-1]) {
block_allowed[block_allowed.length-1].brace_count++;
}
}
else if (
// processing an arrow-function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_ARROW_FUNCTION ||
(
(
// processing a normal function?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FUNCTION ||
// processing a property-function candidate?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_PROPERTY_FUNCTION
) &&
// already found the outer ( ) balanced pair?
block_allowed[block_allowed.length-1].paren_count === 0
)
) {
tokens[tokens.length-1].is_block = true;
// expecting the opening { of the outer { } balanced pair?
if (block_allowed[block_allowed.length-1].brace_count === null) {
block_allowed[block_allowed.length-1].brace_count = 1;
}
// otherwise, keep count to find outer { } balanced pair
else {
block_allowed[block_allowed.length-1].brace_count++;
}
block_allowed[block_allowed.length-1].allowed = true;
}
else if (
// processing a for-loop currently?
block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FOR &&
// already found the outer ( ) balanced pair?
block_allowed[block_allowed.length-1].paren_count === 0
) {
tokens[tokens.length-1].is_block = true;
block_allowed.pop();
block_allowed[block_allowed.length-1].allowed = true;
}
}
// closing } brace?
else if (match[0] === "}") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
if (
// not general block-allowed processing state?
block_allowed[block_allowed.length-1].type !== BLOCK_ALLOWED_GENERAL &&
// still looking for the closing } for the outer { } balanced pair?
block_allowed[block_allowed.length-1].brace_count > 0
) {
block_allowed[block_allowed.length-1].brace_count--;
// found the closing } for the outer { } balanced pair?
if (block_allowed[block_allowed.length-1].brace_count === 0) {
block_allowed.pop();
}
else {
checkAbandonPropertyFunctionCandidate(match[0]);
}
}
block_allowed[block_allowed.length-1].allowed = true;
}
// : is possibly a qualifier for subsequent statement block?
else if (match[0] === ":") {
checkAbandonPropertyFunctionCandidate(match[0]);
// is : part of a statement block label or a switch clause?
if (statement_block_label_candidate ||
switch_clause_candidate
) {
// subsequent statement block allowed
block_allowed[block_allowed.length-1].allowed = true;
}
else {
// subsequent statement block not allowed
block_allowed[block_allowed.length-1].allowed = false;
}
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
}
// ; allows a subsequent { } block, except when inside a for-loop's clauses
else if (match[0] === ";") {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
// processing a for-loop's clauses?
if (block_allowed[block_allowed.length-1].type === BLOCK_ALLOWED_FOR) {
// ; in a for-loop's clauses separates expression-statements only,
// so statement blocks not allowed
block_allowed[block_allowed.length-1].allowed = false;
}
else {
block_allowed[block_allowed.length-1].allowed = true;
}
}
// disqualifier for subsequent statement block?
else if (/^(?:[\[+\-*\/%&\|=,\<\>])$/.test(match[0])) {
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed[block_allowed.length-1].allowed = false;
}
// otherwise, subsequent statement block allowed
else {
block_asi_allowed = true;
statement_block_label_candidate = false;
switch_clause_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed[block_allowed.length-1].allowed = false;
}
}
// starting a regex-literal segment (candidate)?
else if (match[0] === "/") {
// lookback confirms it's an eligible regex?
if (regexLookback()) {
segments.push({
type: SEGMENT_REGEX_LITERAL,
val: match[0]
});
tokens.push(clone(segments[segments.length-1]));
lexing_state = STATE_REGEX_LITERAL_CANDIDATE;
}
// otherwise, just text
else {
saveText(match[0]);
tokens.push({
type: TOKEN_SPECIAL,
val: match[0]
});
}
block_asi_allowed = false;
statement_block_label_candidate = false;
switch_clause_candidate = false;
property_function_candidate = false;
checkAbandonPropertyFunctionCandidate(match[0]);
block_allowed[block_allowed.length-1].allowed = false;
}
}
}
function processSingleLineComment() {
segments[segments.length-1].val += unmatched;
if (match) {
// don't capture the new-line in this comment segment,
// leave it for next match
next_match_idx -= match[0].length;
lexing_state = STATE_GENERAL;
}
}
function processMultiLineComment() {
segments[segments.length-1].val += unmatched;
if (match) {
segments[segments.length-1].val += match[0];
lexing_state = STATE_GENERAL;
// did this multi-line comment span multiple lines?
if (/\r?\n/.test(segments[segments.length-1].val)) {
// check block ASI at this new-line
if (block_asi_allowed) {
block_allowed[block_allowed.length-1].allowed = true;
block_asi_allowed = false;
}
}
}
}
function processStringLiteral() {
var left_context;
segments[segments.length-1].val += unmatched;
segments[segments.length-1].raw += unmatched;
if (match) {
left_context = code.slice(0,next_match_idx - match[0].length);
// is the match at the beginning or is it NOT escaped?
if (!left_context || not_escaped_pattern.test(left_context)) {
// an unescaped new-line in a file's string literal
// is a syntax error
if (/\r?\n/.test(match[0])) {
public_api.warnings.push("Unterminated string literal: " + segments[segments.length-1].val.replace(/[\r\n]+/g,""));
next_match_idx -= match[0].length;
prev_match_idx = next_match_idx;
block_allowed[block_allowed.length-1].allowed = true;
block_asi_allowed = false;
}
else {
segments[segments.length-1].val += match[0];
segments[segments.length-1].raw += match[0];
block_asi_allowed = true;
}
lexing_state = STATE_GENERAL;
}
else {
// include an escaped quote character?
if (match[0] === "\"" || match[0] === "'") {
segments[segments.length-1].val += match[0];
segments[segments.length-1].raw += match[0];
}
// omit escaped new-lines including their \ escape character
else {
segments[segments.length-1].raw += match[0];
segments[segments.length-1].val =
segments[segments.length-1].val.slice(
0,
segments[segments.length-1].val.length-1
)
;
}
}
}
}
function processBacktickLiteral() {
var left_context;
segments[segments.length-1].val += unmatched;
if (match) {
segments[segments.length-1].val += match[0];
left_context = code.slice(0,next_match_idx - match[0].length);
// is the match at the beginning or is it NOT escaped?
if (!left_context || not_escaped_pattern.test(left_context)) {
lexing_state = STATE_GENERAL;
block_asi_allowed = true;
}
}
}
function processRegexLiteral() {
var left_context;
segments[segments.length-1].val += unmatched;
if (match) {
left_context = code.slice(0,next_match_idx - match[0].length);
// any new-line in a file's regex literal is a syntax error
if (/\r?\n/.test(match[0])) {
public_api.warnings.push("Unterminated regular expression literal: " + segments[segments.length-1].val);
next_match_idx -= match[0].length;
prev_match_idx = next_match_idx;
lexing_state = STATE_GENERAL;
block_allowed[block_allowed.length-1].allowed = true;
block_asi_allowed = false;
}
// unescaped [ ?
else if (match[0] === "[" && not_escaped_pattern.test(left_context)) {
segments[segments.length-1].val += match[0];
regex_character_class = true;
}
// unescaped ] ?
else if (match[0] === "]" && not_escaped_pattern.test(left_context)) {
segments[segments.length-1].val += match[0];
regex_character_class = false;
}
// otherwise, must be a /
else {
segments[segments.length-1].val += match[0];
if (
// NOT in a character-class?
!regex_character_class &&
(
// not at the beginning?
!left_context ||
// not escaped?
not_escaped_pattern.test(left_context)
)
) {
lexing_state = STATE_GENERAL;
block_asi_allowed = true;
}
}
}
}
var segments = [],
tokens = [],
match,
prev_match_idx = 0,
next_match_idx = 0,
unmatched = "",
regex,
segment,
block_allowed = [
{
type: BLOCK_ALLOWED_GENERAL,
allowed: true
}
],
block_asi_allowed = false,
statement_block_label_candidate = false,
switch_clause_candidate = false,
property_function_candidate = false,
regex_character_class = false,
normal_function_started = false,
arrow_function_started = false,
lexing_state = 0,
STATE_PROCESSORS = [
processGeneral,
processSingleLineComment,
processMultiLineComment,
processStringLiteral,
processBacktickLiteral,
processRegexLiteral
],
general_state_patterns
;
code = String(code || "");
if (!code || code.length === 0) return segments;
// construct the general-state pattern based on config options
general_state_patterns = [PATTERN_BASE_GENERAL.source];
if (!public_api.opts.overlook_html_comment_markers) {
general_state_patterns.unshift(PATTERN_HTML_COMMENT.source);
}
if (public_api.opts.identify_number_literals) {
general_state_patterns.push(PATTERN_NUMBER_LITERAL.source);
}
if (public_api.opts.identify_simple_literals) {
general_state_patterns.push(PATTERN_SIMPLE_LITERAL.source);
}
STATE_PATTERNS[STATE_GENERAL] = new RegExp(general_state_patterns.join("|"),"g");
while (next_match_idx < code.length) {
unmatched = "";
regex = STATE_PATTERNS[lexing_state];
regex.lastIndex = next_match_idx;
match = regex.exec(code);
if (match) {
prev_match_idx = next_match_idx;
next_match_idx = regex.lastIndex;
// collect the previous string code not matched before this segment
if (prev_match_idx < next_match_idx - match[0].length) {
unmatched = code.slice(prev_match_idx,next_match_idx - match[0].length);
}
}
else {
prev_match_idx = next_match_idx;
next_match_idx = code.length;
unmatched = code.slice(prev_match_idx);
if (!unmatched) break;
}
STATE_PROCESSORS[lexing_state]();
}
// did we end in an abnormal state?
if (lexing_state === STATE_MULTI_LINE_COMMENT) {
segments[segments.length-1].type = SEGMENT_GENERAL;
public_api.warnings.push("Unterminated multi-line comment at end of file");
}
else if (lexing_state === STATE_STRING_LITERAL) {
segments[segments.length-1].type = SEGMENT_GENERAL;
public_api.warnings.push("Unterminated string literal at end of file");
}
else if (lexing_state === STATE_BACKTICK_LITERAL) {
segments[segments.length-1].type = SEGMENT_GENERAL;
public_api.warnings.push("Unterminated template string at end of file");
}
else if (lexing_state === STATE_REGEX_LITERAL_CANDIDATE) {
segments[segments.length-1].type = SEGMENT_GENERAL;
public_api.warnings.push("Unterminated regular expression literal at end of file");
}
tokens.length = 0;
return combineGeneralSegments(segments);
}
function generate(segments) {
var i, ret = "";
for (i=0; i<segments.length; i++) {
ret += (segments[i].raw || segments[i].val || "");
}
return ret;
}
function reset() {
public_api.warnings.length = 0;
}
var SEGMENT_GENERAL = 0,
SEGMENT_COMMENT = 1,
SEGMENT_STRING_LITERAL = 2,
SEGMENT_BACKTICK_LITERAL = 3,
SEGMENT_REGEX_LITERAL = 4,
SEGMENT_NUMBER_LITERAL = 5,
SEGMENT_SIMPLE_LITERAL = 6,
TOKEN_SPECIAL = 50,
STATE_GENERAL = 0,
STATE_SINGLE_LINE_COMMENT = 1,
STATE_MULTI_LINE_COMMENT = 2,
STATE_STRING_LITERAL = 3,
STATE_BACKTICK_LITERAL = 4,
STATE_REGEX_LITERAL_CANDIDATE = 5,
BLOCK_ALLOWED_GENERAL = 0,
BLOCK_ALLOWED_FUNCTION = 1,
BLOCK_ALLOWED_ARROW_FUNCTION = 2,
BLOCK_ALLOWED_PROPERTY_FUNCTION = 3,
BLOCK_ALLOWED_FOR = 4,
not_escaped_pattern = /(?:[^\\]|(?:^|[^\\])(?:\\\\)+)$/,
// source patterns to be combined based on options config
PATTERN_BASE_GENERAL = /\b(?:new|return|throw|delete|in|of|else|void|typeof|yield|if|while|for|with|case|default|debugger|break|continue)\b|\bfunction(?:\s*\*)?|\/\/|\/\*|=>|(?:\r?\n)|[`"'+\-*\/=~!%&,\|;:\?<>\(\)\{\}\[\]]/,
PATTERN_HTML_COMMENT = /(?:<!--|-->)/,
PATTERN_NUMBER_LITERAL = /(?:0[xX][0-9a-fA-F]+)|(?:0[oO][0-7]+)|(?:0[bB][01]+)|(?:\d+\.\d*(?:[eE][+-]?\d+)?)|(?:\.\d+(?:[eE][+-]?\d+)?)|(?:\d+(?:[eE][+-]?\d+)?)/,
PATTERN_SIMPLE_LITERAL = /\b(?:true|false|null|Infinity|NaN|undefined)\b/,
STATE_PATTERNS = [
null, // (placeholder) general-state pattern
/\r?\n/g, // end of single-line comment
/\*\//g, // end of multi-line comment
null, // (placeholder) end of string literal
/[`]/g, // end of backtick literal
/\/[imgyn]*|\r?\n|[\[\]]/g // end of regex
],
public_api,
default_opts = {
overlook_html_comment_markers: false,
identify_number_literals: false,
identify_simple_literals: false
}
;
public_api = {
lex: lex,
generate: generate,
reset: reset,
// a list of warnings (if any) from the lexing
warnings: [],
opts: clone(default_opts),
// public constants for interpreting segment type
SEGMENT: {
GENERAL: SEGMENT_GENERAL,
COMMENT: SEGMENT_COMMENT,
STRING_LITERAL: SEGMENT_STRING_LITERAL,
BACKTICK_LITERAL: SEGMENT_BACKTICK_LITERAL,
REGEX_LITERAL: SEGMENT_REGEX_LITERAL,
NUMBER_LITERAL: SEGMENT_NUMBER_LITERAL,
SIMPLE_LITERAL: SEGMENT_SIMPLE_LITERAL
}
};
return public_api;
});