github.com/googgoog/go-ethereum@v1.9.7/accounts/abi/error.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package abi
    18  
    19  import (
    20  	"errors"
    21  	"fmt"
    22  	"reflect"
    23  )
    24  
    25  var (
    26  	errBadBool = errors.New("abi: improperly encoded boolean value")
    27  )
    28  
    29  // formatSliceString formats the reflection kind with the given slice size
    30  // and returns a formatted string representation.
    31  func formatSliceString(kind reflect.Kind, sliceSize int) string {
    32  	if sliceSize == -1 {
    33  		return fmt.Sprintf("[]%v", kind)
    34  	}
    35  	return fmt.Sprintf("[%d]%v", sliceSize, kind)
    36  }
    37  
    38  // sliceTypeCheck checks that the given slice can by assigned to the reflection
    39  // type in t.
    40  func sliceTypeCheck(t Type, val reflect.Value) error {
    41  	if val.Kind() != reflect.Slice && val.Kind() != reflect.Array {
    42  		return typeErr(formatSliceString(t.Kind, t.Size), val.Type())
    43  	}
    44  
    45  	if t.T == ArrayTy && val.Len() != t.Size {
    46  		return typeErr(formatSliceString(t.Elem.Kind, t.Size), formatSliceString(val.Type().Elem().Kind(), val.Len()))
    47  	}
    48  
    49  	if t.Elem.T == SliceTy {
    50  		if val.Len() > 0 {
    51  			return sliceTypeCheck(*t.Elem, val.Index(0))
    52  		}
    53  	} else if t.Elem.T == ArrayTy {
    54  		return sliceTypeCheck(*t.Elem, val.Index(0))
    55  	}
    56  
    57  	if elemKind := val.Type().Elem().Kind(); elemKind != t.Elem.Kind {
    58  		return typeErr(formatSliceString(t.Elem.Kind, t.Size), val.Type())
    59  	}
    60  	return nil
    61  }
    62  
    63  // typeCheck checks that the given reflection value can be assigned to the reflection
    64  // type in t.
    65  func typeCheck(t Type, value reflect.Value) error {
    66  	if t.T == SliceTy || t.T == ArrayTy {
    67  		return sliceTypeCheck(t, value)
    68  	}
    69  
    70  	// Check base type validity. Element types will be checked later on.
    71  	if t.Kind != value.Kind() {
    72  		return typeErr(t.Kind, value.Kind())
    73  	} else if t.T == FixedBytesTy && t.Size != value.Len() {
    74  		return typeErr(t.Type, value.Type())
    75  	} else {
    76  		return nil
    77  	}
    78  
    79  }
    80  
    81  // typeErr returns a formatted type casting error.
    82  func typeErr(expected, got interface{}) error {
    83  	return fmt.Errorf("abi: cannot use %v as type %v as argument", got, expected)
    84  }