function Parser::checkInvalidEscapeSequences

Checks if the given string or number contains invalid escape sequences

Parameters

string $val Value to check:

bool $number True if the value is a number:

bool $forceLegacyOctalCheck True to force legacy octal: form check

bool $taggedTemplate True if the value is a tagged: template

Return value

void

3 calls to Parser::checkInvalidEscapeSequences()

Parser::parseNumericLiteral in vendor/mck89/peast/lib/Peast/Syntax/Parser.php

Parses a numeric literal

Parser::parseStringLiteral in vendor/mck89/peast/lib/Peast/Syntax/Parser.php

Parses a string literal

Parser::parseTemplateLiteral in vendor/mck89/peast/lib/Peast/Syntax/Parser.php

Parses a template literal

File

vendor/mck89/peast/lib/Peast/Syntax/Parser.php, line 4018

Class

Parser

Parser class

Namespace

Peast\Syntax

Code

protected function checkInvalidEscapeSequences($val, $number = false, $forceLegacyOctalCheck = false, $taggedTemplate = false) {
    if ($this->features->skipEscapeSeqCheckInTaggedTemplates && $taggedTemplate) {
        return;
    }
    $checkLegacyOctal = $forceLegacyOctalCheck || $this->scanner
        ->getStrictMode();
    if ($number) {
        if ($val && $val[0] === "0" && preg_match("#^0[0-9_]+\$#", $val)) {
            if ($checkLegacyOctal) {
                $this->error("Octal literals are not allowed in strict mode");
            }
            if ($this->features->numericLiteralSeparator && strpos($val, '_') !== false) {
                $this->error("Numeric separators are not allowed in legacy octal numbers");
            }
        }
    }
    elseif (strpos($val, "\\") !== false) {
        $hex = "0-9a-fA-F";
        $invalidSyntax = array(
            "x[{$hex}]?[^{$hex}]",
            "x[{$hex}]?\$",
            "u\\{\\}",
            "u\\{(?:[{$hex}]*[^{$hex}\\}]+)+[{$hex}]*\\}",
            "u\\{[^\\}]*\$",
            "u(?!{)[{$hex}]{0,3}[^{$hex}\\{]",
            "u[{$hex}]{0,3}\$",
        );
        if ($checkLegacyOctal) {
            $invalidSyntax[] = "\\d{2}";
            $invalidSyntax[] = "[1-7]";
            $invalidSyntax[] = "0[89]";
        }
        $reg = "#(\\\\+)(" . implode("|", $invalidSyntax) . ")#";
        if (preg_match_all($reg, $val, $matches, PREG_SET_ORDER)) {
            foreach ($matches as $match) {
                if (strlen($match[1]) % 2) {
                    $first = $match[2][0];
                    if ($first === "u") {
                        $err = "Malformed unicode escape sequence";
                    }
                    elseif ($first === "x") {
                        $err = "Malformed hexadecimal escape sequence";
                    }
                    else {
                        $err = "Octal literals are not allowed in strict mode";
                    }
                    $this->error($err);
                }
            }
        }
    }
}