ganache-time-traveler

A testing toolset that allows developers to write unit tests for the Ethereum blockchain.

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Time Contract Example

NOTE:

this only works with ganache-cli
this only works locally

Tool Dependencies

Install

npm i ganache-time-traveler

Usage

add require at the top of your tests

const helper = require('ganache-time-traveler');

add the beforeEach and afterEach hooks into your test file

beforeEach(async() => {
   let snapShot = await helper.takeSnapshot();
   snapshotId = snapShot['result'];
});
 
afterEach(async() => {
   await helper.revertToSnapshot(snapshotId);
});

Breakdown of methods

`advanceTime(<seconds_to_advance_by>)`

Advances the time on the blockchain forward. Takes a single parameter, which is the number of seconds to advance by. Note: for advancetime() to take effect, the block must also be mined using advanceBlock(). See advanceTimeAndBlock() to do both.

`advanceBlock()`

Mines a new block; advances the block forward by 1 block.

`advanceBlockAndSetTime(<new_time>)`

Advances the block forward by 1 and sets the time to a new time.

`advanceTimeAndBlock(<seconds_to_advance_by>)`

Advances the block by 1 in addition to advancing the time on the blockchain forward. Takes a single parameter, which is the number of seconds to advance by.

`takeSnapshot()`

Snapshot the state of the blockchain at the current block. Takes no parameters. Returns the integer id of the snapshot created.

`revertToSnapshot(<id_to_revert_to>)`

Revert the state of the blockchain to a previous snapshot. Takes a single parameter, which is the snapshot id to revert to.

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