terraformDummyRepo2/vendor/github.com/zclconf/go-cty/cty/value_ops.go

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2022-04-03 04:07:16 +00:00
package cty
import (
"fmt"
"math/big"
"github.com/zclconf/go-cty/cty/set"
)
// GoString is an implementation of fmt.GoStringer that produces concise
// source-like representations of values suitable for use in debug messages.
func (val Value) GoString() string {
if val.IsMarked() {
unVal, marks := val.Unmark()
if len(marks) == 1 {
var mark interface{}
for m := range marks {
mark = m
}
return fmt.Sprintf("%#v.Mark(%#v)", unVal, mark)
}
return fmt.Sprintf("%#v.WithMarks(%#v)", unVal, marks)
}
if val == NilVal {
return "cty.NilVal"
}
if val.IsNull() {
return fmt.Sprintf("cty.NullVal(%#v)", val.ty)
}
if val == DynamicVal { // is unknown, so must be before the IsKnown check below
return "cty.DynamicVal"
}
if !val.IsKnown() {
return fmt.Sprintf("cty.UnknownVal(%#v)", val.ty)
}
// By the time we reach here we've dealt with all of the exceptions around
// unknowns and nulls, so we're guaranteed that the values are the
// canonical internal representation of the given type.
switch val.ty {
case Bool:
if val.v.(bool) {
return "cty.True"
}
return "cty.False"
case Number:
fv := val.v.(*big.Float)
// We'll try to use NumberIntVal or NumberFloatVal if we can, since
// the fully-general initializer call is pretty ugly-looking.
if fv.IsInt() {
return fmt.Sprintf("cty.NumberIntVal(%#v)", fv)
}
if rfv, accuracy := fv.Float64(); accuracy == big.Exact {
return fmt.Sprintf("cty.NumberFloatVal(%#v)", rfv)
}
return fmt.Sprintf("cty.MustParseNumberVal(%q)", fv.Text('f', -1))
case String:
return fmt.Sprintf("cty.StringVal(%#v)", val.v)
}
switch {
case val.ty.IsSetType():
vals := val.AsValueSlice()
if len(vals) == 0 {
return fmt.Sprintf("cty.SetValEmpty(%#v)", val.ty.ElementType())
}
return fmt.Sprintf("cty.SetVal(%#v)", vals)
case val.ty.IsListType():
vals := val.AsValueSlice()
if len(vals) == 0 {
return fmt.Sprintf("cty.ListValEmpty(%#v)", val.ty.ElementType())
}
return fmt.Sprintf("cty.ListVal(%#v)", vals)
case val.ty.IsMapType():
vals := val.AsValueMap()
if len(vals) == 0 {
return fmt.Sprintf("cty.MapValEmpty(%#v)", val.ty.ElementType())
}
return fmt.Sprintf("cty.MapVal(%#v)", vals)
case val.ty.IsTupleType():
if val.ty.Equals(EmptyTuple) {
return "cty.EmptyTupleVal"
}
vals := val.AsValueSlice()
return fmt.Sprintf("cty.TupleVal(%#v)", vals)
case val.ty.IsObjectType():
if val.ty.Equals(EmptyObject) {
return "cty.EmptyObjectVal"
}
vals := val.AsValueMap()
return fmt.Sprintf("cty.ObjectVal(%#v)", vals)
case val.ty.IsCapsuleType():
impl := val.ty.CapsuleOps().GoString
if impl == nil {
return fmt.Sprintf("cty.CapsuleVal(%#v, %#v)", val.ty, val.v)
}
return impl(val.EncapsulatedValue())
}
// Default exposes implementation details, so should actually cover
// all of the cases above for good caller UX.
return fmt.Sprintf("cty.Value{ty: %#v, v: %#v}", val.ty, val.v)
}
// Equals returns True if the receiver and the given other value have the
// same type and are exactly equal in value.
//
// As a special case, two null values are always equal regardless of type.
//
// The usual short-circuit rules apply, so the result will be unknown if
// either of the given values are.
//
// Use RawEquals to compare if two values are equal *ignoring* the
// short-circuit rules and the exception for null values.
func (val Value) Equals(other Value) Value {
if val.ContainsMarked() || other.ContainsMarked() {
val, valMarks := val.UnmarkDeep()
other, otherMarks := other.UnmarkDeep()
return val.Equals(other).WithMarks(valMarks, otherMarks)
}
// Start by handling Unknown values before considering types.
// This needs to be done since Null values are always equal regardless of
// type.
switch {
case !val.IsKnown() && !other.IsKnown():
// both unknown
return UnknownVal(Bool)
case val.IsKnown() && !other.IsKnown():
switch {
case val.IsNull(), other.ty.HasDynamicTypes():
// If known is Null, we need to wait for the unknown value since
// nulls of any type are equal.
// An unknown with a dynamic type compares as unknown, which we need
// to check before the type comparison below.
return UnknownVal(Bool)
case !val.ty.Equals(other.ty):
// There is no null comparison or dynamic types, so unequal types
// will never be equal.
return False
default:
return UnknownVal(Bool)
}
case other.IsKnown() && !val.IsKnown():
switch {
case other.IsNull(), val.ty.HasDynamicTypes():
// If known is Null, we need to wait for the unknown value since
// nulls of any type are equal.
// An unknown with a dynamic type compares as unknown, which we need
// to check before the type comparison below.
return UnknownVal(Bool)
case !other.ty.Equals(val.ty):
// There's no null comparison or dynamic types, so unequal types
// will never be equal.
return False
default:
return UnknownVal(Bool)
}
}
switch {
case val.IsNull() && other.IsNull():
// Nulls are always equal, regardless of type
return BoolVal(true)
case val.IsNull() || other.IsNull():
// If only one is null then the result must be false
return BoolVal(false)
}
// Check if there are any nested dynamic values making this comparison
// unknown.
if !val.HasWhollyKnownType() || !other.HasWhollyKnownType() {
// Even if we have dynamic values, we can still determine inequality if
// there is no way the types could later conform.
if val.ty.TestConformance(other.ty) != nil && other.ty.TestConformance(val.ty) != nil {
return BoolVal(false)
}
return UnknownVal(Bool)
}
if !val.ty.Equals(other.ty) {
return BoolVal(false)
}
ty := val.ty
result := false
switch {
case ty == Number:
result = rawNumberEqual(val.v.(*big.Float), other.v.(*big.Float))
case ty == Bool:
result = val.v.(bool) == other.v.(bool)
case ty == String:
// Simple equality is safe because we NFC-normalize strings as they
// enter our world from StringVal, and so we can assume strings are
// always in normal form.
result = val.v.(string) == other.v.(string)
case ty.IsObjectType():
oty := ty.typeImpl.(typeObject)
result = true
for attr, aty := range oty.AttrTypes {
lhs := Value{
ty: aty,
v: val.v.(map[string]interface{})[attr],
}
rhs := Value{
ty: aty,
v: other.v.(map[string]interface{})[attr],
}
eq := lhs.Equals(rhs)
if !eq.IsKnown() {
return UnknownVal(Bool)
}
if eq.False() {
result = false
break
}
}
case ty.IsTupleType():
tty := ty.typeImpl.(typeTuple)
result = true
for i, ety := range tty.ElemTypes {
lhs := Value{
ty: ety,
v: val.v.([]interface{})[i],
}
rhs := Value{
ty: ety,
v: other.v.([]interface{})[i],
}
eq := lhs.Equals(rhs)
if !eq.IsKnown() {
return UnknownVal(Bool)
}
if eq.False() {
result = false
break
}
}
case ty.IsListType():
ety := ty.typeImpl.(typeList).ElementTypeT
if len(val.v.([]interface{})) == len(other.v.([]interface{})) {
result = true
for i := range val.v.([]interface{}) {
lhs := Value{
ty: ety,
v: val.v.([]interface{})[i],
}
rhs := Value{
ty: ety,
v: other.v.([]interface{})[i],
}
eq := lhs.Equals(rhs)
if !eq.IsKnown() {
return UnknownVal(Bool)
}
if eq.False() {
result = false
break
}
}
}
case ty.IsSetType():
s1 := val.v.(set.Set)
s2 := other.v.(set.Set)
equal := true
// Two sets are equal if all of their values are known and all values
// in one are also in the other.
for it := s1.Iterator(); it.Next(); {
rv := it.Value()
if rv == unknown { // "unknown" is the internal representation of unknown-ness
return UnknownVal(Bool)
}
if !s2.Has(rv) {
equal = false
}
}
for it := s2.Iterator(); it.Next(); {
rv := it.Value()
if rv == unknown { // "unknown" is the internal representation of unknown-ness
return UnknownVal(Bool)
}
if !s1.Has(rv) {
equal = false
}
}
result = equal
case ty.IsMapType():
ety := ty.typeImpl.(typeMap).ElementTypeT
if len(val.v.(map[string]interface{})) == len(other.v.(map[string]interface{})) {
result = true
for k := range val.v.(map[string]interface{}) {
if _, ok := other.v.(map[string]interface{})[k]; !ok {
result = false
break
}
lhs := Value{
ty: ety,
v: val.v.(map[string]interface{})[k],
}
rhs := Value{
ty: ety,
v: other.v.(map[string]interface{})[k],
}
eq := lhs.Equals(rhs)
if !eq.IsKnown() {
return UnknownVal(Bool)
}
if eq.False() {
result = false
break
}
}
}
case ty.IsCapsuleType():
impl := val.ty.CapsuleOps().Equals
if impl == nil {
impl := val.ty.CapsuleOps().RawEquals
if impl == nil {
// A capsule type's encapsulated value is a pointer to a value of its
// native type, so we can just compare these to get the identity test
// we need.
return BoolVal(val.v == other.v)
}
return BoolVal(impl(val.v, other.v))
}
ret := impl(val.v, other.v)
if !ret.Type().Equals(Bool) {
panic(fmt.Sprintf("Equals for %#v returned %#v, not cty.Bool", ty, ret.Type()))
}
return ret
default:
// should never happen
panic(fmt.Errorf("unsupported value type %#v in Equals", ty))
}
return BoolVal(result)
}
// NotEqual is a shorthand for Equals followed by Not.
func (val Value) NotEqual(other Value) Value {
return val.Equals(other).Not()
}
// True returns true if the receiver is True, false if False, and panics if
// the receiver is not of type Bool.
//
// This is a helper function to help write application logic that works with
// values, rather than a first-class operation. It does not work with unknown
// or null values. For more robust handling with unknown value
// short-circuiting, use val.Equals(cty.True).
func (val Value) True() bool {
val.assertUnmarked()
if val.ty != Bool {
panic("not bool")
}
return val.Equals(True).v.(bool)
}
// False is the opposite of True.
func (val Value) False() bool {
return !val.True()
}
// RawEquals returns true if and only if the two given values have the same
// type and equal value, ignoring the usual short-circuit rules about
// unknowns and dynamic types.
//
// This method is more appropriate for testing than for real use, since it
// skips over usual semantics around unknowns but as a consequence allows
// testing the result of another operation that is expected to return unknown.
// It returns a primitive Go bool rather than a Value to remind us that it
// is not a first-class value operation.
func (val Value) RawEquals(other Value) bool {
if !val.ty.Equals(other.ty) {
return false
}
if !val.HasSameMarks(other) {
return false
}
// Since we've now checked the marks, we'll unmark for the rest of this...
val = val.unmarkForce()
other = other.unmarkForce()
if (!val.IsKnown()) && (!other.IsKnown()) {
return true
}
if (val.IsKnown() && !other.IsKnown()) || (other.IsKnown() && !val.IsKnown()) {
return false
}
if val.IsNull() && other.IsNull() {
return true
}
if (val.IsNull() && !other.IsNull()) || (other.IsNull() && !val.IsNull()) {
return false
}
if val.ty == DynamicPseudoType && other.ty == DynamicPseudoType {
return true
}
ty := val.ty
switch {
case ty == Number || ty == Bool || ty == String || ty == DynamicPseudoType:
return val.Equals(other).True()
case ty.IsObjectType():
oty := ty.typeImpl.(typeObject)
for attr, aty := range oty.AttrTypes {
lhs := Value{
ty: aty,
v: val.v.(map[string]interface{})[attr],
}
rhs := Value{
ty: aty,
v: other.v.(map[string]interface{})[attr],
}
eq := lhs.RawEquals(rhs)
if !eq {
return false
}
}
return true
case ty.IsTupleType():
tty := ty.typeImpl.(typeTuple)
for i, ety := range tty.ElemTypes {
lhs := Value{
ty: ety,
v: val.v.([]interface{})[i],
}
rhs := Value{
ty: ety,
v: other.v.([]interface{})[i],
}
eq := lhs.RawEquals(rhs)
if !eq {
return false
}
}
return true
case ty.IsListType():
ety := ty.typeImpl.(typeList).ElementTypeT
if len(val.v.([]interface{})) == len(other.v.([]interface{})) {
for i := range val.v.([]interface{}) {
lhs := Value{
ty: ety,
v: val.v.([]interface{})[i],
}
rhs := Value{
ty: ety,
v: other.v.([]interface{})[i],
}
eq := lhs.RawEquals(rhs)
if !eq {
return false
}
}
return true
}
return false
case ty.IsSetType():
// Convert the set values into a slice so that we can compare each
// value. This is safe because the underlying sets are ordered (see
// setRules in set_internals.go), and so the results are guaranteed to
// be in a consistent order for two equal sets
setList1 := val.AsValueSlice()
setList2 := other.AsValueSlice()
// If both physical sets have the same length and they have all of their
// _known_ values in common, we know that both sets also have the same
// number of unknown values.
if len(setList1) != len(setList2) {
return false
}
for i := range setList1 {
eq := setList1[i].RawEquals(setList2[i])
if !eq {
return false
}
}
// If we got here without returning false already then our sets are
// equal enough for RawEquals purposes.
return true
case ty.IsMapType():
ety := ty.typeImpl.(typeMap).ElementTypeT
if !val.HasSameMarks(other) {
return false
}
valUn, _ := val.Unmark()
otherUn, _ := other.Unmark()
if len(valUn.v.(map[string]interface{})) == len(otherUn.v.(map[string]interface{})) {
for k := range valUn.v.(map[string]interface{}) {
if _, ok := otherUn.v.(map[string]interface{})[k]; !ok {
return false
}
lhs := Value{
ty: ety,
v: valUn.v.(map[string]interface{})[k],
}
rhs := Value{
ty: ety,
v: otherUn.v.(map[string]interface{})[k],
}
eq := lhs.RawEquals(rhs)
if !eq {
return false
}
}
return true
}
return false
case ty.IsCapsuleType():
impl := val.ty.CapsuleOps().RawEquals
if impl == nil {
// A capsule type's encapsulated value is a pointer to a value of its
// native type, so we can just compare these to get the identity test
// we need.
return val.v == other.v
}
return impl(val.v, other.v)
default:
// should never happen
panic(fmt.Errorf("unsupported value type %#v in RawEquals", ty))
}
}
// Add returns the sum of the receiver and the given other value. Both values
// must be numbers; this method will panic if not.
func (val Value) Add(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Add(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
ret := new(big.Float)
ret.Add(val.v.(*big.Float), other.v.(*big.Float))
return NumberVal(ret)
}
// Subtract returns receiver minus the given other value. Both values must be
// numbers; this method will panic if not.
func (val Value) Subtract(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Subtract(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
return val.Add(other.Negate())
}
// Negate returns the numeric negative of the receiver, which must be a number.
// This method will panic when given a value of any other type.
func (val Value) Negate() Value {
if val.IsMarked() {
val, valMarks := val.Unmark()
return val.Negate().WithMarks(valMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
ret := new(big.Float).Neg(val.v.(*big.Float))
return NumberVal(ret)
}
// Multiply returns the product of the receiver and the given other value.
// Both values must be numbers; this method will panic if not.
func (val Value) Multiply(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Multiply(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
// find the larger precision of the arguments
resPrec := val.v.(*big.Float).Prec()
otherPrec := other.v.(*big.Float).Prec()
if otherPrec > resPrec {
resPrec = otherPrec
}
// make sure we have enough precision for the product
ret := new(big.Float).SetPrec(512)
ret.Mul(val.v.(*big.Float), other.v.(*big.Float))
// now reduce the precision back to the greater argument, or the minimum
// required by the product.
minPrec := ret.MinPrec()
if minPrec > resPrec {
resPrec = minPrec
}
ret.SetPrec(resPrec)
return NumberVal(ret)
}
// Divide returns the quotient of the receiver and the given other value.
// Both values must be numbers; this method will panic if not.
//
// If the "other" value is exactly zero, this operation will return either
// PositiveInfinity or NegativeInfinity, depending on the sign of the
// receiver value. For some use-cases the presence of infinities may be
// undesirable, in which case the caller should check whether the
// other value equals zero before calling and raise an error instead.
//
// If both values are zero or infinity, this function will panic with
// an instance of big.ErrNaN.
func (val Value) Divide(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Divide(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
ret := new(big.Float)
ret.Quo(val.v.(*big.Float), other.v.(*big.Float))
return NumberVal(ret)
}
// Modulo returns the remainder of an integer division of the receiver and
// the given other value. Both values must be numbers; this method will panic
// if not.
//
// If the "other" value is exactly zero, this operation will return either
// PositiveInfinity or NegativeInfinity, depending on the sign of the
// receiver value. For some use-cases the presence of infinities may be
// undesirable, in which case the caller should check whether the
// other value equals zero before calling and raise an error instead.
//
// This operation is primarily here for use with nonzero natural numbers.
// Modulo with "other" as a non-natural number gets somewhat philosophical,
// and this function takes a position on what that should mean, but callers
// may wish to disallow such things outright or implement their own modulo
// if they disagree with the interpretation used here.
func (val Value) Modulo(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Modulo(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
// We cheat a bit here with infinities, just abusing the Multiply operation
// to get an infinite result of the correct sign.
if val == PositiveInfinity || val == NegativeInfinity || other == PositiveInfinity || other == NegativeInfinity {
return val.Multiply(other)
}
if other.RawEquals(Zero) {
return val
}
// FIXME: This is a bit clumsy. Should come back later and see if there's a
// more straightforward way to do this.
rat := val.Divide(other)
ratFloorInt, _ := rat.v.(*big.Float).Int(nil)
// start with a copy of the original larger value so that we do not lose
// precision.
v := val.v.(*big.Float)
work := new(big.Float).Copy(v).SetInt(ratFloorInt)
work.Mul(other.v.(*big.Float), work)
work.Sub(v, work)
return NumberVal(work)
}
// Absolute returns the absolute (signless) value of the receiver, which must
// be a number or this method will panic.
func (val Value) Absolute() Value {
if val.IsMarked() {
val, valMarks := val.Unmark()
return val.Absolute().WithMarks(valMarks)
}
if shortCircuit := mustTypeCheck(Number, Number, val); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Number)
return *shortCircuit
}
ret := (&big.Float{}).Abs(val.v.(*big.Float))
return NumberVal(ret)
}
// GetAttr returns the value of the given attribute of the receiver, which
// must be of an object type that has an attribute of the given name.
// This method will panic if the receiver type is not compatible.
//
// The method will also panic if the given attribute name is not defined
// for the value's type. Use the attribute-related methods on Type to
// check for the validity of an attribute before trying to use it.
//
// This method may be called on a value whose type is DynamicPseudoType,
// in which case the result will also be DynamicVal.
func (val Value) GetAttr(name string) Value {
if val.IsMarked() {
val, valMarks := val.Unmark()
return val.GetAttr(name).WithMarks(valMarks)
}
if val.ty == DynamicPseudoType {
return DynamicVal
}
if !val.ty.IsObjectType() {
panic("value is not an object")
}
name = NormalizeString(name)
if !val.ty.HasAttribute(name) {
panic("value has no attribute of that name")
}
attrType := val.ty.AttributeType(name)
if !val.IsKnown() {
return UnknownVal(attrType)
}
return Value{
ty: attrType,
v: val.v.(map[string]interface{})[name],
}
}
// Index returns the value of an element of the receiver, which must have
// either a list, map or tuple type. This method will panic if the receiver
// type is not compatible.
//
// The key value must be the correct type for the receving collection: a
// number if the collection is a list or tuple, or a string if it is a map.
// In the case of a list or tuple, the given number must be convertable to int
// or this method will panic. The key may alternatively be of
// DynamicPseudoType, in which case the result itself is an unknown of the
// collection's element type.
//
// The result is of the receiver collection's element type, or in the case
// of a tuple the type of the specific element index requested.
//
// This method may be called on a value whose type is DynamicPseudoType,
// in which case the result will also be the DynamicValue.
func (val Value) Index(key Value) Value {
if val.IsMarked() || key.IsMarked() {
val, valMarks := val.Unmark()
key, keyMarks := key.Unmark()
return val.Index(key).WithMarks(valMarks, keyMarks)
}
if val.ty == DynamicPseudoType {
return DynamicVal
}
switch {
case val.Type().IsListType():
elty := val.Type().ElementType()
if key.Type() == DynamicPseudoType {
return UnknownVal(elty)
}
if key.Type() != Number {
panic("element key for list must be number")
}
if !key.IsKnown() {
return UnknownVal(elty)
}
if !val.IsKnown() {
return UnknownVal(elty)
}
index, accuracy := key.v.(*big.Float).Int64()
if accuracy != big.Exact || index < 0 {
panic("element key for list must be non-negative integer")
}
return Value{
ty: elty,
v: val.v.([]interface{})[index],
}
case val.Type().IsMapType():
elty := val.Type().ElementType()
if key.Type() == DynamicPseudoType {
return UnknownVal(elty)
}
if key.Type() != String {
panic("element key for map must be string")
}
if !key.IsKnown() {
return UnknownVal(elty)
}
if !val.IsKnown() {
return UnknownVal(elty)
}
keyStr := key.v.(string)
return Value{
ty: elty,
v: val.v.(map[string]interface{})[keyStr],
}
case val.Type().IsTupleType():
if key.Type() == DynamicPseudoType {
return DynamicVal
}
if key.Type() != Number {
panic("element key for tuple must be number")
}
if !key.IsKnown() {
return DynamicVal
}
index, accuracy := key.v.(*big.Float).Int64()
if accuracy != big.Exact || index < 0 {
panic("element key for list must be non-negative integer")
}
eltys := val.Type().TupleElementTypes()
if !val.IsKnown() {
return UnknownVal(eltys[index])
}
return Value{
ty: eltys[index],
v: val.v.([]interface{})[index],
}
default:
panic("not a list, map, or tuple type")
}
}
// HasIndex returns True if the receiver (which must be supported for Index)
// has an element with the given index key, or False if it does not.
//
// The result will be UnknownVal(Bool) if either the collection or the
// key value are unknown.
//
// This method will panic if the receiver is not indexable, but does not
// impose any panic-causing type constraints on the key.
func (val Value) HasIndex(key Value) Value {
if val.IsMarked() || key.IsMarked() {
val, valMarks := val.Unmark()
key, keyMarks := key.Unmark()
return val.HasIndex(key).WithMarks(valMarks, keyMarks)
}
if val.ty == DynamicPseudoType {
return UnknownVal(Bool)
}
switch {
case val.Type().IsListType():
if key.Type() == DynamicPseudoType {
return UnknownVal(Bool)
}
if key.Type() != Number {
return False
}
if !key.IsKnown() {
return UnknownVal(Bool)
}
if !val.IsKnown() {
return UnknownVal(Bool)
}
index, accuracy := key.v.(*big.Float).Int64()
if accuracy != big.Exact || index < 0 {
return False
}
return BoolVal(int(index) < len(val.v.([]interface{})) && index >= 0)
case val.Type().IsMapType():
if key.Type() == DynamicPseudoType {
return UnknownVal(Bool)
}
if key.Type() != String {
return False
}
if !key.IsKnown() {
return UnknownVal(Bool)
}
if !val.IsKnown() {
return UnknownVal(Bool)
}
keyStr := key.v.(string)
_, exists := val.v.(map[string]interface{})[keyStr]
return BoolVal(exists)
case val.Type().IsTupleType():
if key.Type() == DynamicPseudoType {
return UnknownVal(Bool)
}
if key.Type() != Number {
return False
}
if !key.IsKnown() {
return UnknownVal(Bool)
}
index, accuracy := key.v.(*big.Float).Int64()
if accuracy != big.Exact || index < 0 {
return False
}
length := val.Type().Length()
return BoolVal(int(index) < length && index >= 0)
default:
panic("not a list, map, or tuple type")
}
}
// HasElement returns True if the receiver (which must be of a set type)
// has the given value as an element, or False if it does not.
//
// The result will be UnknownVal(Bool) if either the set or the
// given value are unknown.
//
// This method will panic if the receiver is not a set, or if it is a null set.
func (val Value) HasElement(elem Value) Value {
if val.IsMarked() || elem.IsMarked() {
val, valMarks := val.Unmark()
elem, elemMarks := elem.Unmark()
return val.HasElement(elem).WithMarks(valMarks, elemMarks)
}
ty := val.Type()
if !ty.IsSetType() {
panic("not a set type")
}
if !val.IsKnown() || !elem.IsKnown() {
return UnknownVal(Bool)
}
if val.IsNull() {
panic("can't call HasElement on a nil value")
}
if !ty.ElementType().Equals(elem.Type()) {
return False
}
s := val.v.(set.Set)
return BoolVal(s.Has(elem.v))
}
// Length returns the length of the receiver, which must be a collection type
// or tuple type, as a number value. If the receiver is not a compatible type
// then this method will panic.
//
// If the receiver is unknown then the result is also unknown.
//
// If the receiver is null then this function will panic.
//
// Note that Length is not supported for strings. To determine the length
// of a string, use the Length function in funcs/stdlib.
func (val Value) Length() Value {
if val.IsMarked() {
val, valMarks := val.Unmark()
return val.Length().WithMarks(valMarks)
}
if val.Type().IsTupleType() {
// For tuples, we can return the length even if the value is not known.
return NumberIntVal(int64(val.Type().Length()))
}
if !val.IsKnown() {
return UnknownVal(Number)
}
if val.Type().IsSetType() {
// The Length rules are a little different for sets because if any
// unknown values are present then the values they are standing in for
// may or may not be equal to other elements in the set, and thus they
// may or may not coalesce with other elements and produce fewer
// items in the resulting set.
storeLength := int64(val.v.(set.Set).Length())
if storeLength == 1 || val.IsWhollyKnown() {
// If our set is wholly known then we know its length.
//
// We also know the length if the physical store has only one
// element, even if that element is unknown, because there's
// nothing else in the set for it to coalesce with and a single
// unknown value cannot represent more than one known value.
return NumberIntVal(storeLength)
}
// Otherwise, we cannot predict the length.
return UnknownVal(Number)
}
return NumberIntVal(int64(val.LengthInt()))
}
// LengthInt is like Length except it returns an int. It has the same behavior
// as Length except that it will panic if the receiver is unknown.
//
// This is an integration method provided for the convenience of code bridging
// into Go's type system.
//
// For backward compatibility with an earlier implementation error, LengthInt's
// result can disagree with Length's result for any set containing unknown
// values. Length can potentially indicate the set's length is unknown in that
// case, whereas LengthInt will return the maximum possible length as if the
// unknown values were each a placeholder for a value not equal to any other
// value in the set.
func (val Value) LengthInt() int {
val.assertUnmarked()
if val.Type().IsTupleType() {
// For tuples, we can return the length even if the value is not known.
return val.Type().Length()
}
if val.Type().IsObjectType() {
// For objects, the length is the number of attributes associated with the type.
return len(val.Type().AttributeTypes())
}
if !val.IsKnown() {
panic("value is not known")
}
if val.IsNull() {
panic("value is null")
}
switch {
case val.ty.IsListType():
return len(val.v.([]interface{}))
case val.ty.IsSetType():
// NOTE: This is technically not correct in cases where the set
// contains unknown values, because in that case we can't know how
// many known values those unknown values are standing in for -- they
// might coalesce with other values once known.
//
// However, this incorrect behavior is preserved for backward
// compatibility with callers that were relying on LengthInt rather
// than calling Length. Instead of panicking when a set contains an
// unknown value, LengthInt returns the largest possible length.
return val.v.(set.Set).Length()
case val.ty.IsMapType():
return len(val.v.(map[string]interface{}))
default:
panic("value is not a collection")
}
}
// ElementIterator returns an ElementIterator for iterating the elements
// of the receiver, which must be a collection type, a tuple type, or an object
// type. If called on a method of any other type, this method will panic.
//
// The value must be Known and non-Null, or this method will panic.
//
// If the receiver is of a list type, the returned keys will be of type Number
// and the values will be of the list's element type.
//
// If the receiver is of a map type, the returned keys will be of type String
// and the value will be of the map's element type. Elements are passed in
// ascending lexicographical order by key.
//
// If the receiver is of a set type, each element is returned as both the
// key and the value, since set members are their own identity.
//
// If the receiver is of a tuple type, the returned keys will be of type Number
// and the value will be of the corresponding element's type.
//
// If the receiver is of an object type, the returned keys will be of type
// String and the value will be of the corresponding attributes's type.
//
// ElementIterator is an integration method, so it cannot handle Unknown
// values. This method will panic if the receiver is Unknown.
func (val Value) ElementIterator() ElementIterator {
val.assertUnmarked()
if !val.IsKnown() {
panic("can't use ElementIterator on unknown value")
}
if val.IsNull() {
panic("can't use ElementIterator on null value")
}
return elementIterator(val)
}
// CanIterateElements returns true if the receiver can support the
// ElementIterator method (and by extension, ForEachElement) without panic.
func (val Value) CanIterateElements() bool {
return canElementIterator(val)
}
// ForEachElement executes a given callback function for each element of
// the receiver, which must be a collection type or tuple type, or this method
// will panic.
//
// ForEachElement uses ElementIterator internally, and so the values passed
// to the callback are as described for ElementIterator.
//
// Returns true if the iteration exited early due to the callback function
// returning true, or false if the loop ran to completion.
//
// ForEachElement is an integration method, so it cannot handle Unknown
// values. This method will panic if the receiver is Unknown.
func (val Value) ForEachElement(cb ElementCallback) bool {
val.assertUnmarked()
it := val.ElementIterator()
for it.Next() {
key, val := it.Element()
stop := cb(key, val)
if stop {
return true
}
}
return false
}
// Not returns the logical inverse of the receiver, which must be of type
// Bool or this method will panic.
func (val Value) Not() Value {
if val.IsMarked() {
val, valMarks := val.Unmark()
return val.Not().WithMarks(valMarks)
}
if shortCircuit := mustTypeCheck(Bool, Bool, val); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Bool)
return *shortCircuit
}
return BoolVal(!val.v.(bool))
}
// And returns the result of logical AND with the receiver and the other given
// value, which must both be of type Bool or this method will panic.
func (val Value) And(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.And(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Bool, Bool, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Bool)
return *shortCircuit
}
return BoolVal(val.v.(bool) && other.v.(bool))
}
// Or returns the result of logical OR with the receiver and the other given
// value, which must both be of type Bool or this method will panic.
func (val Value) Or(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.Or(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Bool, Bool, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Bool)
return *shortCircuit
}
return BoolVal(val.v.(bool) || other.v.(bool))
}
// LessThan returns True if the receiver is less than the other given value,
// which must both be numbers or this method will panic.
func (val Value) LessThan(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.LessThan(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Bool, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Bool)
return *shortCircuit
}
return BoolVal(val.v.(*big.Float).Cmp(other.v.(*big.Float)) < 0)
}
// GreaterThan returns True if the receiver is greater than the other given
// value, which must both be numbers or this method will panic.
func (val Value) GreaterThan(other Value) Value {
if val.IsMarked() || other.IsMarked() {
val, valMarks := val.Unmark()
other, otherMarks := other.Unmark()
return val.GreaterThan(other).WithMarks(valMarks, otherMarks)
}
if shortCircuit := mustTypeCheck(Number, Bool, val, other); shortCircuit != nil {
shortCircuit = forceShortCircuitType(shortCircuit, Bool)
return *shortCircuit
}
return BoolVal(val.v.(*big.Float).Cmp(other.v.(*big.Float)) > 0)
}
// LessThanOrEqualTo is equivalent to LessThan and Equal combined with Or.
func (val Value) LessThanOrEqualTo(other Value) Value {
return val.LessThan(other).Or(val.Equals(other))
}
// GreaterThanOrEqualTo is equivalent to GreaterThan and Equal combined with Or.
func (val Value) GreaterThanOrEqualTo(other Value) Value {
return val.GreaterThan(other).Or(val.Equals(other))
}
// AsString returns the native string from a non-null, non-unknown cty.String
// value, or panics if called on any other value.
func (val Value) AsString() string {
val.assertUnmarked()
if val.ty != String {
panic("not a string")
}
if val.IsNull() {
panic("value is null")
}
if !val.IsKnown() {
panic("value is unknown")
}
return val.v.(string)
}
// AsBigFloat returns a big.Float representation of a non-null, non-unknown
// cty.Number value, or panics if called on any other value.
//
// For more convenient conversions to other native numeric types, use the
// "gocty" package.
func (val Value) AsBigFloat() *big.Float {
val.assertUnmarked()
if val.ty != Number {
panic("not a number")
}
if val.IsNull() {
panic("value is null")
}
if !val.IsKnown() {
panic("value is unknown")
}
// Copy the float so that callers can't mutate our internal state
return new(big.Float).Copy(val.v.(*big.Float))
}
// AsValueSlice returns a []cty.Value representation of a non-null, non-unknown
// value of any type that CanIterateElements, or panics if called on
// any other value.
//
// For more convenient conversions to slices of more specific types, use
// the "gocty" package.
func (val Value) AsValueSlice() []Value {
val.assertUnmarked()
l := val.LengthInt()
if l == 0 {
return nil
}
ret := make([]Value, 0, l)
for it := val.ElementIterator(); it.Next(); {
_, v := it.Element()
ret = append(ret, v)
}
return ret
}
// AsValueMap returns a map[string]cty.Value representation of a non-null,
// non-unknown value of any type that CanIterateElements, or panics if called
// on any other value.
//
// For more convenient conversions to maps of more specific types, use
// the "gocty" package.
func (val Value) AsValueMap() map[string]Value {
val.assertUnmarked()
l := val.LengthInt()
if l == 0 {
return nil
}
ret := make(map[string]Value, l)
for it := val.ElementIterator(); it.Next(); {
k, v := it.Element()
ret[k.AsString()] = v
}
return ret
}
// AsValueSet returns a ValueSet representation of a non-null,
// non-unknown value of any collection type, or panics if called
// on any other value.
//
// Unlike AsValueSlice and AsValueMap, this method requires specifically a
// collection type (list, set or map) and does not allow structural types
// (tuple or object), because the ValueSet type requires homogenous
// element types.
//
// The returned ValueSet can store only values of the receiver's element type.
func (val Value) AsValueSet() ValueSet {
val.assertUnmarked()
if !val.Type().IsCollectionType() {
panic("not a collection type")
}
// We don't give the caller our own set.Set (assuming we're a cty.Set value)
// because then the caller could mutate our internals, which is forbidden.
// Instead, we will construct a new set and append our elements into it.
ret := NewValueSet(val.Type().ElementType())
for it := val.ElementIterator(); it.Next(); {
_, v := it.Element()
ret.Add(v)
}
return ret
}
// EncapsulatedValue returns the native value encapsulated in a non-null,
// non-unknown capsule-typed value, or panics if called on any other value.
//
// The result is the same pointer that was passed to CapsuleVal to create
// the value. Since cty considers values to be immutable, it is strongly
// recommended to treat the encapsulated value itself as immutable too.
func (val Value) EncapsulatedValue() interface{} {
val.assertUnmarked()
if !val.Type().IsCapsuleType() {
panic("not a capsule-typed value")
}
return val.v
}