go.ketch.com/lib/goja@v0.0.1/object_goslice_reflect.go (about)

     1  package goja
     2  
     3  import (
     4  	"math"
     5  	"math/bits"
     6  	"reflect"
     7  
     8  	"go.ketch.com/lib/goja/unistring"
     9  )
    10  
    11  type objectGoSliceReflect struct {
    12  	objectGoArrayReflect
    13  }
    14  
    15  func (o *objectGoSliceReflect) init() {
    16  	o.objectGoArrayReflect._init()
    17  	o.lengthProp.writable = true
    18  	o.putIdx = o._putIdx
    19  }
    20  
    21  func (o *objectGoSliceReflect) _putIdx(idx int, v Value, throw bool) bool {
    22  	if idx >= o.fieldsValue.Len() {
    23  		o.grow(idx + 1)
    24  	}
    25  	return o.objectGoArrayReflect._putIdx(idx, v, throw)
    26  }
    27  
    28  func (o *objectGoSliceReflect) grow(size int) {
    29  	oldcap := o.fieldsValue.Cap()
    30  	if oldcap < size {
    31  		n := reflect.MakeSlice(o.fieldsValue.Type(), size, growCap(size, o.fieldsValue.Len(), oldcap))
    32  		reflect.Copy(n, o.fieldsValue)
    33  		o.fieldsValue.Set(n)
    34  		l := len(o.valueCache)
    35  		if l > size {
    36  			l = size
    37  		}
    38  		for i, w := range o.valueCache[:l] {
    39  			if w != nil {
    40  				w.setReflectValue(o.fieldsValue.Index(i))
    41  			}
    42  		}
    43  	} else {
    44  		tail := o.fieldsValue.Slice(o.fieldsValue.Len(), size)
    45  		zero := reflect.Zero(o.fieldsValue.Type().Elem())
    46  		for i := 0; i < tail.Len(); i++ {
    47  			tail.Index(i).Set(zero)
    48  		}
    49  		o.fieldsValue.SetLen(size)
    50  	}
    51  	o.updateLen()
    52  }
    53  
    54  func (o *objectGoSliceReflect) shrink(size int) {
    55  	o.valueCache.shrink(size)
    56  	tail := o.fieldsValue.Slice(size, o.fieldsValue.Len())
    57  	zero := reflect.Zero(o.fieldsValue.Type().Elem())
    58  	for i := 0; i < tail.Len(); i++ {
    59  		tail.Index(i).Set(zero)
    60  	}
    61  	o.fieldsValue.SetLen(size)
    62  	o.updateLen()
    63  }
    64  
    65  func (o *objectGoSliceReflect) putLength(v uint32, throw bool) bool {
    66  	if bits.UintSize == 32 && v > math.MaxInt32 {
    67  		panic(rangeError("Integer value overflows 32-bit int"))
    68  	}
    69  	newLen := int(v)
    70  	curLen := o.fieldsValue.Len()
    71  	if newLen > curLen {
    72  		o.grow(newLen)
    73  	} else if newLen < curLen {
    74  		o.shrink(newLen)
    75  	}
    76  	return true
    77  }
    78  
    79  func (o *objectGoSliceReflect) setOwnStr(name unistring.String, val Value, throw bool) bool {
    80  	if name == "length" {
    81  		return o.putLength(o.val.runtime.toLengthUint32(val), throw)
    82  	}
    83  	return o.objectGoArrayReflect.setOwnStr(name, val, throw)
    84  }
    85  
    86  func (o *objectGoSliceReflect) defineOwnPropertyStr(name unistring.String, descr PropertyDescriptor, throw bool) bool {
    87  	if name == "length" {
    88  		return o.val.runtime.defineArrayLength(&o.lengthProp, descr, o.putLength, throw)
    89  	}
    90  	return o.objectGoArrayReflect.defineOwnPropertyStr(name, descr, throw)
    91  }