github.com/hxx258456/ccgo@v0.0.5-0.20230213014102-48b35f46f66f/internal/reflectlite/tostring_test.go (about)

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Formatting of reflection types and values for debugging.
     6  // Not defined as methods so they do not need to be linked into most binaries;
     7  // the functions are not used by the library itself, only in tests.
     8  
     9  package reflectlite_test
    10  
    11  import (
    12  	"reflect"
    13  	"strconv"
    14  
    15  	. "github.com/hxx258456/ccgo/internal/reflectlite"
    16  )
    17  
    18  // valueToString returns a textual representation of the reflection value val.
    19  // For debugging only.
    20  func valueToString(v Value) string {
    21  	return valueToStringImpl(reflect.ValueOf(ToInterface(v)))
    22  }
    23  
    24  func valueToStringImpl(val reflect.Value) string {
    25  	var str string
    26  	if !val.IsValid() {
    27  		return "<zero Value>"
    28  	}
    29  	typ := val.Type()
    30  	switch val.Kind() {
    31  	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
    32  		return strconv.FormatInt(val.Int(), 10)
    33  	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
    34  		return strconv.FormatUint(val.Uint(), 10)
    35  	case reflect.Float32, reflect.Float64:
    36  		return strconv.FormatFloat(val.Float(), 'g', -1, 64)
    37  	case reflect.Complex64, reflect.Complex128:
    38  		c := val.Complex()
    39  		return strconv.FormatFloat(real(c), 'g', -1, 64) + "+" + strconv.FormatFloat(imag(c), 'g', -1, 64) + "i"
    40  	case reflect.String:
    41  		return val.String()
    42  	case reflect.Bool:
    43  		if val.Bool() {
    44  			return "true"
    45  		} else {
    46  			return "false"
    47  		}
    48  	case reflect.Ptr:
    49  		v := val
    50  		str = typ.String() + "("
    51  		if v.IsNil() {
    52  			str += "0"
    53  		} else {
    54  			str += "&" + valueToStringImpl(v.Elem())
    55  		}
    56  		str += ")"
    57  		return str
    58  	case reflect.Array, reflect.Slice:
    59  		v := val
    60  		str += typ.String()
    61  		str += "{"
    62  		for i := 0; i < v.Len(); i++ {
    63  			if i > 0 {
    64  				str += ", "
    65  			}
    66  			str += valueToStringImpl(v.Index(i))
    67  		}
    68  		str += "}"
    69  		return str
    70  	case reflect.Map:
    71  		str += typ.String()
    72  		str += "{"
    73  		str += "<can't iterate on maps>"
    74  		str += "}"
    75  		return str
    76  	case reflect.Chan:
    77  		str = typ.String()
    78  		return str
    79  	case reflect.Struct:
    80  		t := typ
    81  		v := val
    82  		str += t.String()
    83  		str += "{"
    84  		for i, n := 0, v.NumField(); i < n; i++ {
    85  			if i > 0 {
    86  				str += ", "
    87  			}
    88  			str += valueToStringImpl(v.Field(i))
    89  		}
    90  		str += "}"
    91  		return str
    92  	case reflect.Interface:
    93  		return typ.String() + "(" + valueToStringImpl(val.Elem()) + ")"
    94  	case reflect.Func:
    95  		return typ.String() + "(arg)"
    96  	default:
    97  		panic("valueToString: can't print type " + typ.String())
    98  	}
    99  }