mirror of
https://github.com/RGBCube/serenity
synced 2025-07-25 15:07:45 +00:00
LibJS: Handle hex and unicode escape sequences in string literals
Introduces the following syntax: '\x55' '\u26a0' '\u{1f41e}'
This commit is contained in:
parent
b3090678a9
commit
e415dd4e9c
5 changed files with 118 additions and 9 deletions
|
@ -27,6 +27,7 @@
|
|||
#include "Token.h"
|
||||
#include <AK/Assertions.h>
|
||||
#include <AK/StringBuilder.h>
|
||||
#include <AK/Utf32View.h>
|
||||
#include <ctype.h>
|
||||
|
||||
namespace JS {
|
||||
|
@ -72,13 +73,26 @@ double Token::double_value() const
|
|||
return strtod(value_string.characters(), nullptr);
|
||||
}
|
||||
|
||||
String Token::string_value() const
|
||||
static u32 hex2int(char x)
|
||||
{
|
||||
ASSERT(isxdigit(x));
|
||||
if (x >= '0' && x <= '9')
|
||||
return x - '0';
|
||||
return 10u + (tolower(x) - 'a');
|
||||
}
|
||||
|
||||
String Token::string_value(StringValueStatus& status) const
|
||||
{
|
||||
ASSERT(type() == TokenType::StringLiteral || type() == TokenType::TemplateLiteralString);
|
||||
auto is_template = type() == TokenType::TemplateLiteralString;
|
||||
|
||||
auto offset = type() == TokenType::TemplateLiteralString ? 0 : 1;
|
||||
|
||||
auto encoding_failure = [&status](StringValueStatus parse_status) -> String {
|
||||
status = parse_status;
|
||||
return {};
|
||||
};
|
||||
|
||||
StringBuilder builder;
|
||||
for (size_t i = offset; i < m_value.length() - offset; ++i) {
|
||||
if (m_value[i] == '\\' && i + 1 < m_value.length() - offset) {
|
||||
|
@ -114,14 +128,62 @@ String Token::string_value() const
|
|||
case '\\':
|
||||
builder.append('\\');
|
||||
break;
|
||||
case 'x': {
|
||||
if (i + 2 >= m_value.length() - offset)
|
||||
return encoding_failure(StringValueStatus::MalformedHexEscape);
|
||||
|
||||
auto digit1 = m_value[++i];
|
||||
auto digit2 = m_value[++i];
|
||||
if (!isxdigit(digit1) || !isxdigit(digit2))
|
||||
return encoding_failure(StringValueStatus::MalformedHexEscape);
|
||||
builder.append(static_cast<char>(hex2int(digit1) * 16 + hex2int(digit2)));
|
||||
break;
|
||||
}
|
||||
case 'u': {
|
||||
if (i + 1 >= m_value.length() - offset)
|
||||
return encoding_failure(StringValueStatus::MalformedUnicodeEscape);
|
||||
u32 code_point = m_value[++i];
|
||||
|
||||
if (code_point == '{') {
|
||||
code_point = 0;
|
||||
do {
|
||||
if (i + 1 >= m_value.length() - offset)
|
||||
return encoding_failure(StringValueStatus::MalformedUnicodeEscape);
|
||||
|
||||
auto ch = m_value[++i];
|
||||
if (!isxdigit(ch))
|
||||
return encoding_failure(StringValueStatus::MalformedUnicodeEscape);
|
||||
|
||||
auto new_code_point = (code_point << 4u) | hex2int(ch);
|
||||
if (new_code_point < code_point)
|
||||
return encoding_failure(StringValueStatus::UnicodeEscapeOverflow);
|
||||
code_point = new_code_point;
|
||||
} while (m_value[i + 1] != '}');
|
||||
++i;
|
||||
} else {
|
||||
if (i + 3 >= m_value.length() - offset || !isxdigit(code_point))
|
||||
return encoding_failure(StringValueStatus::MalformedUnicodeEscape);
|
||||
|
||||
code_point = hex2int(code_point);
|
||||
for (int j = 0; j < 3; ++j) {
|
||||
auto ch = m_value[++i];
|
||||
if (!isxdigit(ch))
|
||||
return encoding_failure(StringValueStatus::MalformedUnicodeEscape);
|
||||
code_point = (code_point << 4u) | hex2int(ch);
|
||||
}
|
||||
}
|
||||
|
||||
builder.append({ &code_point, 1 });
|
||||
break;
|
||||
}
|
||||
default:
|
||||
if (is_template && (m_value[i] == '$' || m_value[i] == '`')) {
|
||||
builder.append(m_value[i]);
|
||||
} else {
|
||||
// FIXME: Also parse octal, hex and unicode sequences
|
||||
// should anything else generate a syntax error?
|
||||
builder.append(m_value[i]);
|
||||
break;
|
||||
}
|
||||
|
||||
// FIXME: Also parse octal. Should anything else generate a syntax error?
|
||||
builder.append(m_value[i]);
|
||||
}
|
||||
} else {
|
||||
builder.append(m_value[i]);
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue