github.com/ethereumproject/go-ethereum@v5.5.2+incompatible/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  	"fmt"
    21  	"reflect"
    22  )
    23  
    24  // formatSliceString formats the reflection kind with the given slice size
    25  // and returns a formatted string representation.
    26  func formatSliceString(kind reflect.Kind, sliceSize int) string {
    27  	if sliceSize == -1 {
    28  		return fmt.Sprintf("[]%v", kind)
    29  	}
    30  	return fmt.Sprintf("[%d]%v", sliceSize, kind)
    31  }
    32  
    33  // sliceTypeCheck checks that the given slice can by assigned to the reflection
    34  // type in t.
    35  func sliceTypeCheck(t Type, val reflect.Value) error {
    36  	if val.Kind() != reflect.Slice && val.Kind() != reflect.Array {
    37  		return typeErr(formatSliceString(t.Kind, t.SliceSize), val.Type())
    38  	}
    39  	if t.IsArray && val.Len() != t.SliceSize {
    40  		return typeErr(formatSliceString(t.Elem.Kind, t.SliceSize), formatSliceString(val.Type().Elem().Kind(), val.Len()))
    41  	}
    42  
    43  	if t.Elem.IsSlice {
    44  		if val.Len() > 0 {
    45  			return sliceTypeCheck(*t.Elem, val.Index(0))
    46  		}
    47  	} else if t.Elem.IsArray {
    48  		return sliceTypeCheck(*t.Elem, val.Index(0))
    49  	}
    50  
    51  	if elemKind := val.Type().Elem().Kind(); elemKind != t.Elem.Kind {
    52  		return typeErr(formatSliceString(t.Elem.Kind, t.SliceSize), val.Type())
    53  	}
    54  	return nil
    55  }
    56  
    57  // typeCheck checks that the given reflection value can be assigned to the reflection
    58  // type in t.
    59  func typeCheck(t Type, value reflect.Value) error {
    60  	if t.IsSlice || t.IsArray {
    61  		return sliceTypeCheck(t, value)
    62  	}
    63  
    64  	// Check base type validity. Element types will be checked later on.
    65  	if t.Kind != value.Kind() {
    66  		return typeErr(t.Kind, value.Kind())
    67  	}
    68  	return nil
    69  }
    70  
    71  // typeErr returns a formatted type casting error.
    72  func typeErr(expected, got interface{}) error {
    73  	return fmt.Errorf("abi: cannot use %v as type %v as argument", got, expected)
    74  }