# All files / web3-eth-abi/src type.js

96.55% Statements 84/87
87.5% Branches 21/24
94.74% Functions 18/19
96.55% Lines 84/87

    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    2561x
    1x

    1x
    7x
    7x

    1x

    1x

    1036x

    1061x

    1061x

    1x
    1561x
    1561x

    1x
    893x
    893x

    1x
    41x
    41x
    41x

    1x

    148x
    148x

    148x

    1x
    766x

    1x

    3679x

    1x
    275x
    275x

    25x
    25x
    25x

    25x
    25x

    25x
    51x

    25x

    250x

    11x
    11x
    11x

    11x
    11x
    23x

    11x

    239x

    1x
    337x

    337x

    21x
    21x
    21x
    21x

    21x
    21x
    21x
    21x

    21x
    37x

    21x

    316x

    30x
    30x
    30x

    30x
    30x
    30x
    30x

    30x
    64x

    30x

    286x

    33x
    33x
    33x
    33x
    33x
    33x

    253x
    253x
    253x

    1x
     var f = require('./formatters');
    var SolidityParam = require('./param');

    /**
     * SolidityType prototype is used to encode/decode solidity params of certain type
     */
    var SolidityType = function (config) {
        this._inputFormatter = config.inputFormatter;
        this._outputFormatter = config.outputFormatter;
    };

    /**
     * Should be used to determine if this SolidityType do match given name
     *
     * @method isType
     * @param {String} name
     * @return {Bool} true if type match this SolidityType, otherwise false
     */
    SolidityType.prototype.isType = function (name) {
        throw "This method should be overwritten for type " + name;
    };

    /**
     * Should be used to determine what is the length of static part in given type
     *
     * @method staticPartLength
     * @param {String} name
     * @return {Number} length of static part in bytes
     */
    SolidityType.prototype.staticPartLength = function (name) {
        // If name isn't an array then treat it like a single element array.
        return (this.nestedTypes(name) || ['[1]'])
            .map(function (type) {
                // the length of the nested array
                return parseInt(type.slice(1, -1), 10) || 1;
            })
            .reduce(function (previous, current) {
                return previous * current;
            // all basic types are 32 bytes long
            }, 32);
    };

    /**
     * Should be used to determine if type is dynamic array
     * eg:
     * "type[]" => true
     * "type[4]" => false
     *
     * @method isDynamicArray
     * @param {String} name
     * @return {Bool} true if the type is dynamic array
     */
    SolidityType.prototype.isDynamicArray = function (name) {
        var nestedTypes = this.nestedTypes(name);
        return !!nestedTypes && !nestedTypes[nestedTypes.length - 1].match(/[0-9]{1,}/g);
    };

    /**
     * Should be used to determine if type is static array
     * eg:
     * "type[]" => false
     * "type[4]" => true
     *
     * @method isStaticArray
     * @param {String} name
     * @return {Bool} true if the type is static array
     */
    SolidityType.prototype.isStaticArray = function (name) {
        var nestedTypes = this.nestedTypes(name);
        return !!nestedTypes && !!nestedTypes[nestedTypes.length - 1].match(/[0-9]{1,}/g);
    };

    /**
     * Should return length of static array
     * eg.
     * "int[32]" => 32
     * "int256[14]" => 14
     * "int[2][3]" => 3
     * "int" => 1
     * "int[1]" => 1
     * "int[]" => 1
     *
     * @method staticArrayLength
     * @param {String} name
     * @return {Number} static array length
     */
    SolidityType.prototype.staticArrayLength = function (name) {
        var nestedTypes = this.nestedTypes(name);
        Eif (nestedTypes) {
           return parseInt(nestedTypes[nestedTypes.length - 1].match(/[0-9]{1,}/g) || 1);
        }
        return 1;
    };

    /**
     * Should return nested type
     * eg.
     * "int[32]" => "int"
     * "int256[14]" => "int256"
     * "int[2][3]" => "int[2]"
     * "int" => "int"
     * "int[]" => "int"
     *
     * @method nestedName
     * @param {String} name
     * @return {String} nested name
     */
    SolidityType.prototype.nestedName = function (name) {
        // remove last [] in name
        var nestedTypes = this.nestedTypes(name);
        Iif (!nestedTypes) {
            return name;
        }

        return name.substr(0, name.length - nestedTypes[nestedTypes.length - 1].length);
    };

    /**
     * Should return true if type has dynamic size by default
     * such types are "string", "bytes"
     *
     * @method isDynamicType
     * @param {String} name
     * @return {Bool} true if is dynamic, otherwise false
     */
    SolidityType.prototype.isDynamicType = function () {
        return false;
    };

    /**
     * Should return array of nested types
     * eg.
     * "int[2][3][]" => ["[2]", "[3]", "[]"]
     * "int[] => ["[]"]
     * "int" => null
     *
     * @method nestedTypes
     * @param {String} name
     * @return {Array} array of nested types
     */
    SolidityType.prototype.nestedTypes = function (name) {
        // return list of strings eg. "[]", "[3]", "[]", "[2]"
        return name.match(/(\[[0-9]*\])/g);
    };

    /**
     * Should be used to encode the value
     *
     * @method encode
     * @param {Object} value
     * @param {String} name
     * @return {String} encoded value
     */
    SolidityType.prototype.encode = function (value, name) {
        var self = this;
        if (this.isDynamicArray(name)) {

            return (function () {
                var length = value.length;                          // in int
                var nestedName = self.nestedName(name);

                var result = [];
                result.push(f.formatInputInt(length).encode());

                value.forEach(function (v) {
                    result.push(self.encode(v, nestedName));
                });

                return result;
            })();

        } else if (this.isStaticArray(name)) {

            return (function () {
                var length = self.staticArrayLength(name);          // in int
                var nestedName = self.nestedName(name);

                var result = [];
                for (var i = 0; i < length; i++) {
                    result.push(self.encode(value[i], nestedName));
                }

                return result;
            })();

        }

        return this._inputFormatter(value, name).encode();
    };

    /**
     * Should be used to decode value from bytes
     *
     * @method decode
     * @param {String} bytes
     * @param {Number} offset in bytes
     * @param {String} name type name
     * @returns {Object} decoded value
     */
    SolidityType.prototype.decode = function (bytes, offset, name) {
        var self = this;

        if (this.isDynamicArray(name)) {

            return (function () {
                var arrayOffset = parseInt('0x' + bytes.substr(offset * 2, 64)); // in bytes
                var length = parseInt('0x' + bytes.substr(arrayOffset * 2, 64)); // in int
                var arrayStart = arrayOffset + 32; // array starts after length; // in bytes

                var nestedName = self.nestedName(name);
                var nestedStaticPartLength = self.staticPartLength(nestedName);  // in bytes
                var roundedNestedStaticPartLength = Math.floor((nestedStaticPartLength + 31) / 32) * 32;
                var result = [];

                for (var i = 0; i < length * roundedNestedStaticPartLength; i += roundedNestedStaticPartLength) {
                    result.push(self.decode(bytes, arrayStart + i, nestedName));
                }

                return result;
            })();

        } else if (this.isStaticArray(name)) {

            return (function () {
                var length = self.staticArrayLength(name);                      // in int
                var arrayStart = offset;                                        // in bytes

                var nestedName = self.nestedName(name);
                var nestedStaticPartLength = self.staticPartLength(nestedName); // in bytes
                var roundedNestedStaticPartLength = Math.floor((nestedStaticPartLength + 31) / 32) * 32;
                var result = [];

                for (var i = 0; i < length * roundedNestedStaticPartLength; i += roundedNestedStaticPartLength) {
                    result.push(self.decode(bytes, arrayStart + i, nestedName));
                }

                return result;
            })();
        } else if (this.isDynamicType(name)) {

            return (function () {
                var dynamicOffset = parseInt('0x' + bytes.substr(offset * 2, 64));      // in bytes
                var length = parseInt('0x' + bytes.substr(dynamicOffset * 2, 64));      // in bytes
                var roundedLength = Math.floor((length + 31) / 32);                     // in int
                var param = new SolidityParam(bytes.substr(dynamicOffset * 2, ( 1 + roundedLength) * 64), 0, bytes);
                return self._outputFormatter(param, name);
            })();
        }

        var length = this.staticPartLength(name);
        var param = new SolidityParam(bytes.substr(offset * 2, length * 2), undefined, bytes);
        return this._outputFormatter(param, name);
    };

    module.exports = SolidityType;