ethers.js/lib.esm/abi/coders/abstract-coder.js

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import { defineProperties, concat, getBytesCopy, getNumber, hexlify, toBeArray, toBigInt, toNumber, assert, assertArgument } from "../../utils/index.js";
/**
* @_ignore:
*/
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export const WordSize = 32;
const Padding = new Uint8Array(WordSize);
// Properties used to immediate pass through to the underlying object
// - `then` is used to detect if an object is a Promise for await
const passProperties = ["then"];
const _guard = {};
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function throwError(name, error) {
const wrapped = new Error(`deferred error during ABI decoding triggered accessing ${name}`);
wrapped.error = error;
throw wrapped;
}
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/**
* A [[Result]] is a sub-class of Array, which allows accessing any
* of its values either positionally by its index or, if keys are
* provided by its name.
*
* @_docloc: api/abi
*/
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export class Result extends Array {
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#names;
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/**
* @private
*/
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constructor(...args) {
// To properly sub-class Array so the other built-in
// functions work, the constructor has to behave fairly
// well. So, in the event we are created via fromItems()
// we build the read-only Result object we want, but on
// any other input, we use the default constructor
// constructor(guard: any, items: Array<any>, keys?: Array<null | string>);
const guard = args[0];
let items = args[1];
let names = (args[2] || []).slice();
let wrap = true;
if (guard !== _guard) {
items = args;
names = [];
wrap = false;
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}
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// Can't just pass in ...items since an array of length 1
// is a special case in the super.
super(items.length);
items.forEach((item, index) => { this[index] = item; });
// Find all unique keys
const nameCounts = names.reduce((accum, name) => {
if (typeof (name) === "string") {
accum.set(name, (accum.get(name) || 0) + 1);
}
return accum;
}, (new Map()));
// Remove any key thats not unique
this.#names = Object.freeze(items.map((item, index) => {
const name = names[index];
if (name != null && nameCounts.get(name) === 1) {
return name;
}
return null;
}));
if (!wrap) {
return;
}
// A wrapped Result is immutable
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Object.freeze(this);
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// Proxy indices and names so we can trap deferred errors
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return new Proxy(this, {
get: (target, prop, receiver) => {
if (typeof (prop) === "string") {
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// Index accessor
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if (prop.match(/^[0-9]+$/)) {
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const index = getNumber(prop, "%index");
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if (index < 0 || index >= this.length) {
throw new RangeError("out of result range");
}
const item = target[index];
if (item instanceof Error) {
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throwError(`index ${index}`, item);
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}
return item;
}
// Pass important checks (like `then` for Promise) through
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if (passProperties.indexOf(prop) >= 0) {
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return Reflect.get(target, prop, receiver);
}
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const value = target[prop];
if (value instanceof Function) {
// Make sure functions work with private variables
// See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy#no_private_property_forwarding
return function (...args) {
return value.apply((this === receiver) ? target : this, args);
};
}
else if (!(prop in target)) {
// Possible name accessor
return target.getValue.apply((this === receiver) ? target : this, [prop]);
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}
}
return Reflect.get(target, prop, receiver);
}
});
}
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/**
* Returns the Result as a normal Array.
*
* This will throw if there are any outstanding deferred
* errors.
*/
toArray() {
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const result = [];
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this.forEach((item, index) => {
if (item instanceof Error) {
throwError(`index ${index}`, item);
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}
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result.push(item);
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});
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return result;
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}
/**
* Returns the Result as an Object with each name-value pair.
*
* This will throw if any value is unnamed, or if there are
* any outstanding deferred errors.
*/
toObject() {
return this.#names.reduce((accum, name, index) => {
assert(name != null, "value at index ${ index } unnamed", "UNSUPPORTED_OPERATION", {
operation: "toObject()"
});
// Add values for names that don't conflict
if (!(name in accum)) {
accum[name] = this.getValue(name);
}
return accum;
}, {});
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}
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/**
* @_ignore
*/
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slice(start, end) {
if (start == null) {
start = 0;
}
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if (start < 0) {
start += this.length;
if (start < 0) {
start = 0;
}
}
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if (end == null) {
end = this.length;
}
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if (end < 0) {
end += this.length;
if (end < 0) {
end = 0;
}
}
if (end > this.length) {
end = this.length;
}
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const result = [], names = [];
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for (let i = start; i < end; i++) {
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result.push(this[i]);
names.push(this.#names[i]);
}
return new Result(_guard, result, names);
}
/**
* @_ignore
*/
filter(callback, thisArg) {
const result = [], names = [];
for (let i = 0; i < this.length; i++) {
const item = this[i];
if (item instanceof Error) {
throwError(`index ${i}`, item);
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}
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if (callback.call(thisArg, item, i, this)) {
result.push(item);
names.push(this.#names[i]);
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}
}
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return new Result(_guard, result, names);
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}
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/**
* Returns the value for %%name%%.
*
* Since it is possible to have a key whose name conflicts with
* a method on a [[Result]] or its superclass Array, or any
* JavaScript keyword, this ensures all named values are still
* accessible by name.
*/
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getValue(name) {
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const index = this.#names.indexOf(name);
if (index === -1) {
return undefined;
}
const value = this[index];
if (value instanceof Error) {
throwError(`property ${JSON.stringify(name)}`, value.error);
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}
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return value;
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}
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/**
* Creates a new [[Result]] for %%items%% with each entry
* also accessible by its corresponding name in %%keys%%.
*/
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static fromItems(items, keys) {
return new Result(_guard, items, keys);
}
}
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/**
* Returns all errors found in a [[Result]].
*
* Since certain errors encountered when creating a [[Result]] do
* not impact the ability to continue parsing data, they are
* deferred until they are actually accessed. Hence a faulty string
* in an Event that is never used does not impact the program flow.
*
* However, sometimes it may be useful to access, identify or
* validate correctness of a [[Result]].
*
* @_docloc api/abi
*/
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export function checkResultErrors(result) {
// Find the first error (if any)
const errors = [];
const checkErrors = function (path, object) {
if (!Array.isArray(object)) {
return;
}
for (let key in object) {
const childPath = path.slice();
childPath.push(key);
try {
checkErrors(childPath, object[key]);
}
catch (error) {
errors.push({ path: childPath, error: error });
}
}
};
checkErrors([], result);
return errors;
}
function getValue(value) {
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let bytes = toBeArray(value);
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assert(bytes.length <= WordSize, "value out-of-bounds", "BUFFER_OVERRUN", { buffer: bytes, length: WordSize, offset: bytes.length });
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if (bytes.length !== WordSize) {
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bytes = getBytesCopy(concat([Padding.slice(bytes.length % WordSize), bytes]));
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}
return bytes;
}
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/**
* @_ignore
*/
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export class Coder {
// The coder name:
// - address, uint256, tuple, array, etc.
name;
// The fully expanded type, including composite types:
// - address, uint256, tuple(address,bytes), uint256[3][4][], etc.
type;
// The localName bound in the signature, in this example it is "baz":
// - tuple(address foo, uint bar) baz
localName;
// Whether this type is dynamic:
// - Dynamic: bytes, string, address[], tuple(boolean[]), etc.
// - Not Dynamic: address, uint256, boolean[3], tuple(address, uint8)
dynamic;
constructor(name, type, localName, dynamic) {
defineProperties(this, { name, type, localName, dynamic }, {
name: "string", type: "string", localName: "string", dynamic: "boolean"
});
}
_throwError(message, value) {
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assertArgument(false, message, this.localName, value);
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}
}
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/**
* @_ignore
*/
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export class Writer {
// An array of WordSize lengthed objects to concatenation
#data;
#dataLength;
constructor() {
this.#data = [];
this.#dataLength = 0;
}
get data() {
return concat(this.#data);
}
get length() { return this.#dataLength; }
#writeData(data) {
this.#data.push(data);
this.#dataLength += data.length;
return data.length;
}
appendWriter(writer) {
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return this.#writeData(getBytesCopy(writer.data));
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}
// Arrayish item; pad on the right to *nearest* WordSize
writeBytes(value) {
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let bytes = getBytesCopy(value);
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const paddingOffset = bytes.length % WordSize;
if (paddingOffset) {
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bytes = getBytesCopy(concat([bytes, Padding.slice(paddingOffset)]));
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}
return this.#writeData(bytes);
}
// Numeric item; pad on the left *to* WordSize
writeValue(value) {
return this.#writeData(getValue(value));
}
// Inserts a numeric place-holder, returning a callback that can
// be used to asjust the value later
writeUpdatableValue() {
const offset = this.#data.length;
this.#data.push(Padding);
this.#dataLength += WordSize;
return (value) => {
this.#data[offset] = getValue(value);
};
}
}
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/**
* @_ignore
*/
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export class Reader {
// Allows incomplete unpadded data to be read; otherwise an error
// is raised if attempting to overrun the buffer. This is required
// to deal with an old Solidity bug, in which event data for
// external (not public thoguh) was tightly packed.
allowLoose;
#data;
#offset;
constructor(data, allowLoose) {
defineProperties(this, { allowLoose: !!allowLoose });
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this.#data = getBytesCopy(data);
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this.#offset = 0;
}
get data() { return hexlify(this.#data); }
get dataLength() { return this.#data.length; }
get consumed() { return this.#offset; }
get bytes() { return new Uint8Array(this.#data); }
#peekBytes(offset, length, loose) {
let alignedLength = Math.ceil(length / WordSize) * WordSize;
if (this.#offset + alignedLength > this.#data.length) {
if (this.allowLoose && loose && this.#offset + length <= this.#data.length) {
alignedLength = length;
}
else {
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assert(false, "data out-of-bounds", "BUFFER_OVERRUN", {
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buffer: getBytesCopy(this.#data),
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length: this.#data.length,
offset: this.#offset + alignedLength
});
}
}
return this.#data.slice(this.#offset, this.#offset + alignedLength);
}
// Create a sub-reader with the same underlying data, but offset
subReader(offset) {
return new Reader(this.#data.slice(this.#offset + offset), this.allowLoose);
}
// Read bytes
readBytes(length, loose) {
let bytes = this.#peekBytes(0, length, !!loose);
this.#offset += bytes.length;
// @TODO: Make sure the length..end bytes are all 0?
return bytes.slice(0, length);
}
// Read a numeric values
readValue() {
return toBigInt(this.readBytes(WordSize));
}
readIndex() {
return toNumber(this.readBytes(WordSize));
}
}
//# sourceMappingURL=abstract-coder.js.map