serenity/Userland/Libraries/LibJS/Runtime/Value.h
Linus Groh ad7aa05cc6 LibJS: Implement the CreateListFromArrayLike() abstract operation
We already have two separate implementations of this, so let's do it
properly. The optional value type check is done by a callback function
that returns Result<void, ErrorType> - value type accepted or message
for TypeError, that is.
2021-06-09 23:46:37 +01:00

391 lines
11 KiB
C++

/*
* Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2020-2021, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Assertions.h>
#include <AK/BitCast.h>
#include <AK/Format.h>
#include <AK/Forward.h>
#include <AK/Function.h>
#include <AK/Result.h>
#include <AK/String.h>
#include <AK/Types.h>
#include <LibJS/Forward.h>
#include <math.h>
// 2 ** 53 - 1
static constexpr double MAX_ARRAY_LIKE_INDEX = 9007199254740991.0;
// Unique bit representation of negative zero (only sign bit set)
static constexpr u64 NEGATIVE_ZERO_BITS = ((u64)1 << 63);
namespace JS {
class Value {
public:
enum class Type {
Empty,
Undefined,
Null,
Int32,
Double,
String,
Object,
Boolean,
Symbol,
Accessor,
BigInt,
NativeProperty,
};
enum class PreferredType {
Default,
String,
Number,
};
bool is_empty() const { return m_type == Type::Empty; }
bool is_undefined() const { return m_type == Type::Undefined; }
bool is_null() const { return m_type == Type::Null; }
bool is_number() const { return m_type == Type::Int32 || m_type == Type::Double; }
bool is_string() const { return m_type == Type::String; }
bool is_object() const { return m_type == Type::Object; }
bool is_boolean() const { return m_type == Type::Boolean; }
bool is_symbol() const { return m_type == Type::Symbol; }
bool is_accessor() const { return m_type == Type::Accessor; };
bool is_bigint() const { return m_type == Type::BigInt; };
bool is_native_property() const { return m_type == Type::NativeProperty; }
bool is_nullish() const { return is_null() || is_undefined(); }
bool is_cell() const { return is_string() || is_accessor() || is_object() || is_bigint() || is_symbol() || is_native_property(); }
bool is_array(GlobalObject&) const;
bool is_function() const;
bool is_constructor() const;
bool is_regexp(GlobalObject&) const;
bool is_nan() const { return is_number() && __builtin_isnan(as_double()); }
bool is_infinity() const { return is_number() && __builtin_isinf(as_double()); }
bool is_positive_infinity() const { return is_number() && __builtin_isinf_sign(as_double()) > 0; }
bool is_negative_infinity() const { return is_number() && __builtin_isinf_sign(as_double()) < 0; }
bool is_positive_zero() const { return is_number() && bit_cast<u64>(as_double()) == 0; }
bool is_negative_zero() const { return is_number() && bit_cast<u64>(as_double()) == NEGATIVE_ZERO_BITS; }
bool is_integer() const { return is_finite_number() && (i32)as_double() == as_double(); }
bool is_finite_number() const
{
if (!is_number())
return false;
auto number = as_double();
return !__builtin_isnan(number) && !__builtin_isinf(number);
}
Value()
: m_type(Type::Empty)
{
}
explicit Value(bool value)
: m_type(Type::Boolean)
{
m_value.as_bool = value;
}
explicit Value(double value)
{
bool is_negative_zero = bit_cast<u64>(value) == NEGATIVE_ZERO_BITS;
if (value >= NumericLimits<i32>::min() && value <= NumericLimits<i32>::max() && trunc(value) == value && !is_negative_zero) {
m_type = Type::Int32;
m_value.as_i32 = static_cast<i32>(value);
} else {
m_type = Type::Double;
m_value.as_double = value;
}
}
explicit Value(unsigned long value)
{
if (value > NumericLimits<i32>::max()) {
m_value.as_double = static_cast<double>(value);
m_type = Type::Double;
} else {
m_value.as_i32 = static_cast<i32>(value);
m_type = Type::Int32;
}
}
explicit Value(unsigned value)
{
if (value > NumericLimits<i32>::max()) {
m_value.as_double = static_cast<double>(value);
m_type = Type::Double;
} else {
m_value.as_i32 = static_cast<i32>(value);
m_type = Type::Int32;
}
}
explicit Value(i32 value)
: m_type(Type::Int32)
{
m_value.as_i32 = value;
}
Value(const Object* object)
: m_type(object ? Type::Object : Type::Null)
{
m_value.as_object = const_cast<Object*>(object);
}
Value(const PrimitiveString* string)
: m_type(Type::String)
{
m_value.as_string = const_cast<PrimitiveString*>(string);
}
Value(const Symbol* symbol)
: m_type(Type::Symbol)
{
m_value.as_symbol = const_cast<Symbol*>(symbol);
}
Value(const Accessor* accessor)
: m_type(Type::Accessor)
{
m_value.as_accessor = const_cast<Accessor*>(accessor);
}
Value(const BigInt* bigint)
: m_type(Type::BigInt)
{
m_value.as_bigint = const_cast<BigInt*>(bigint);
}
Value(const NativeProperty* native_property)
: m_type(Type::NativeProperty)
{
m_value.as_native_property = const_cast<NativeProperty*>(native_property);
}
explicit Value(Type type)
: m_type(type)
{
}
Type type() const { return m_type; }
double as_double() const
{
VERIFY(is_number());
if (m_type == Type::Int32)
return m_value.as_i32;
return m_value.as_double;
}
bool as_bool() const
{
VERIFY(type() == Type::Boolean);
return m_value.as_bool;
}
Object& as_object()
{
VERIFY(type() == Type::Object);
return *m_value.as_object;
}
const Object& as_object() const
{
VERIFY(type() == Type::Object);
return *m_value.as_object;
}
PrimitiveString& as_string()
{
VERIFY(is_string());
return *m_value.as_string;
}
const PrimitiveString& as_string() const
{
VERIFY(is_string());
return *m_value.as_string;
}
Symbol& as_symbol()
{
VERIFY(is_symbol());
return *m_value.as_symbol;
}
const Symbol& as_symbol() const
{
VERIFY(is_symbol());
return *m_value.as_symbol;
}
Cell& as_cell()
{
VERIFY(is_cell());
return *m_value.as_cell;
}
Accessor& as_accessor()
{
VERIFY(is_accessor());
return *m_value.as_accessor;
}
BigInt& as_bigint()
{
VERIFY(is_bigint());
return *m_value.as_bigint;
}
NativeProperty& as_native_property()
{
VERIFY(is_native_property());
return *m_value.as_native_property;
}
Array& as_array();
Function& as_function();
i32 as_i32() const;
u32 as_u32() const;
u64 encoded() const { return m_value.encoded; }
String to_string(GlobalObject&, bool legacy_null_to_empty_string = false) const;
PrimitiveString* to_primitive_string(GlobalObject&);
Value to_primitive(GlobalObject&, PreferredType preferred_type = PreferredType::Default) const;
Object* to_object(GlobalObject&) const;
Value to_numeric(GlobalObject&) const;
Value to_number(GlobalObject&) const;
BigInt* to_bigint(GlobalObject&) const;
double to_double(GlobalObject&) const;
StringOrSymbol to_property_key(GlobalObject&) const;
i32 to_i32(GlobalObject& global_object) const
{
if (m_type == Type::Int32)
return m_value.as_i32;
return to_i32_slow_case(global_object);
}
u32 to_u32(GlobalObject&) const;
size_t to_length(GlobalObject&) const;
size_t to_index(GlobalObject&) const;
double to_integer_or_infinity(GlobalObject&) const;
bool to_boolean() const;
String to_string_without_side_effects() const;
Value value_or(Value fallback) const
{
if (is_empty())
return fallback;
return *this;
}
String typeof() const;
private:
Type m_type { Type::Empty };
i32 to_i32_slow_case(GlobalObject&) const;
union {
bool as_bool;
i32 as_i32;
double as_double;
PrimitiveString* as_string;
Symbol* as_symbol;
Object* as_object;
Cell* as_cell;
Accessor* as_accessor;
BigInt* as_bigint;
NativeProperty* as_native_property;
u64 encoded;
} m_value { .encoded = 0 };
};
inline Value js_undefined()
{
return Value(Value::Type::Undefined);
}
inline Value js_null()
{
return Value(Value::Type::Null);
}
inline Value js_nan()
{
return Value(NAN);
}
inline Value js_infinity()
{
return Value(INFINITY);
}
inline Value js_negative_infinity()
{
return Value(-INFINITY);
}
inline void Cell::Visitor::visit(Value value)
{
if (value.is_cell())
visit_impl(value.as_cell());
}
Value greater_than(GlobalObject&, Value lhs, Value rhs);
Value greater_than_equals(GlobalObject&, Value lhs, Value rhs);
Value less_than(GlobalObject&, Value lhs, Value rhs);
Value less_than_equals(GlobalObject&, Value lhs, Value rhs);
Value bitwise_and(GlobalObject&, Value lhs, Value rhs);
Value bitwise_or(GlobalObject&, Value lhs, Value rhs);
Value bitwise_xor(GlobalObject&, Value lhs, Value rhs);
Value bitwise_not(GlobalObject&, Value);
Value unary_plus(GlobalObject&, Value);
Value unary_minus(GlobalObject&, Value);
Value left_shift(GlobalObject&, Value lhs, Value rhs);
Value right_shift(GlobalObject&, Value lhs, Value rhs);
Value unsigned_right_shift(GlobalObject&, Value lhs, Value rhs);
Value add(GlobalObject&, Value lhs, Value rhs);
Value sub(GlobalObject&, Value lhs, Value rhs);
Value mul(GlobalObject&, Value lhs, Value rhs);
Value div(GlobalObject&, Value lhs, Value rhs);
Value mod(GlobalObject&, Value lhs, Value rhs);
Value exp(GlobalObject&, Value lhs, Value rhs);
Value in(GlobalObject&, Value lhs, Value rhs);
Value instance_of(GlobalObject&, Value lhs, Value rhs);
Value ordinary_has_instance(GlobalObject&, Value lhs, Value rhs);
bool abstract_eq(GlobalObject&, Value lhs, Value rhs);
bool strict_eq(Value lhs, Value rhs);
bool same_value(Value lhs, Value rhs);
bool same_value_zero(Value lhs, Value rhs);
bool same_value_non_numeric(Value lhs, Value rhs);
TriState abstract_relation(GlobalObject&, bool left_first, Value lhs, Value rhs);
Function* get_method(GlobalObject& global_object, Value, const PropertyName&);
size_t length_of_array_like(GlobalObject&, const Object&);
Object* species_constructor(GlobalObject&, const Object&, Object& default_constructor);
Value require_object_coercible(GlobalObject&, Value);
MarkedValueList create_list_from_array_like(GlobalObject&, Value, AK::Function<Result<void, ErrorType>(Value)> = {});
}
namespace AK {
template<>
struct Formatter<JS::Value> : Formatter<StringView> {
void format(FormatBuilder& builder, const JS::Value& value)
{
Formatter<StringView>::format(builder, value.is_empty() ? "<empty>" : value.to_string_without_side_effects());
}
};
}