[Ethereum] “before all” hook: prepare suite

There is something wrong with the latest truffle version. To solve this problem I had to do the following things to find a truffle version that worked.

First check for available versions of truffle with the following command.

npm view truffle versions

Then for each item on the list starting from the latest version. I uninstalled truffle with

npm uninstall -g truffle

then installed the next oldest version with

npm install -g truffle@<version#>

then deleted the build folder

then compiled the project with

truffle compile

then ran

truffle test

if this fails move on to the next oldest version and repeat the test.

In my case a working version of truffle was 4.1.4

There is an issue in a way you use HDWalletProvider when configuring development network in truffle-config.js.

You should add it like:

provider: () => new HDWalletProvider('your mnemonic', 'http://127.0.0.1:7545')

For me, it helped. Additional info can be found here.