GoScrobble/web/node_modules/@webassemblyjs/wast-parser/lib/string-literals.js

94 lines
2.1 KiB
JavaScript
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.parseString = parseString;
// string literal characters cannot contain control codes
var CONTROL_CODES = [0, // null
7, // bell
8, // backspace
9, // horizontal
10, // line feed
11, // vertical tab
12, // form feed
13, // carriage return
26, // Control-Z
27, // escape
127 // delete
]; // escaped sequences can either be a two character hex value, or one of the
// following single character codes
function decodeControlCharacter(char) {
switch (char) {
case "t":
return 0x09;
case "n":
return 0x0a;
case "r":
return 0x0d;
case '"':
return 0x22;
case "":
return 0x27;
case "\\":
return 0x5c;
}
return -1;
}
var ESCAPE_CHAR = 92; // backslash
var QUOTE_CHAR = 34; // backslash
// parse string as per the spec:
// https://webassembly.github.io/spec/core/multipage/text/values.html#text-string
function parseString(value) {
var byteArray = [];
var index = 0;
while (index < value.length) {
var charCode = value.charCodeAt(index);
if (CONTROL_CODES.indexOf(charCode) !== -1) {
throw new Error("ASCII control characters are not permitted within string literals");
}
if (charCode === QUOTE_CHAR) {
throw new Error("quotes are not permitted within string literals");
}
if (charCode === ESCAPE_CHAR) {
var firstChar = value.substr(index + 1, 1);
var decodedControlChar = decodeControlCharacter(firstChar);
if (decodedControlChar !== -1) {
// single character escaped values, e.g. \r
byteArray.push(decodedControlChar);
index += 2;
} else {
// hex escaped values, e.g. \2a
var hexValue = value.substr(index + 1, 2);
if (!/^[0-9A-F]{2}$/i.test(hexValue)) {
throw new Error("invalid character encoding");
}
byteArray.push(parseInt(hexValue, 16));
index += 3;
}
} else {
// ASCII encoded values
byteArray.push(charCode);
index++;
}
}
return byteArray;
}