trying-foundry

Notes:

• It is extremely fast.
• Tests are written in solidity, and can be run using forge test. To run a specific test file: forge test --match-contract <Contract Name>
• Test files will end in .t.sol and are present inside the test folder.
• Test cases natively support fuzzing and we don't have to pass fuzzing inputs, they are auto generated.
• Logging can be done using emit log().
• By default logs are not visible so to make them visible run forge test -vv.
• Script files are also written in solidity and they broadcast solidity files to the EVM using vm.broadcast() method.
• Script files end in .s.sol and are present inside the script folder.
• Local blockchain can be run using anvil.
• Deploying to localhost and calling functions using cast(kind of like hardhat console):
  • Step 1: Run anvil local blockchain using anvil
  • Step 2: Set PRIVATE_KEY environment variable using export PRIVATE_KEY=<Pvt Key From anvil>
  • Step 3: Run script to deploy on the local blockchain (in a different terminal instance):

    forge script script/Greetings.s.sol:GreetingsScript --fork-url http://localhost:8545 --private-key $PRIVATE_KEY --broadcast

  • Step 4: Store contract address in another environment variable using export CONTRACT_ADDRESS=<Contract address from anvil>
  • Step 5: Call greet() using cast: cast call $CONTRACT_ADDRESS "greet()(string)"
  • Step 6: Performing transactions using cast: cast send $CONTRACT_ADDRESS "updateGreeting(string)" "Hey" --private-key $PRIVATE_KEY
  • Step 7; Read greeting again to check if it changed: Same as Step 5
• Using OpenZeppelin contracts:
  • Step 1: Commit code up till now.
  • Step 2: Run: forge install OpenZeppelin/openzeppelin-contracts - It will not install if you have not committed the code up till now. This could be because they are going to add OZ as a git submodule (In the lib folder).
  • Step 3: Configure remappings: To tell local environment where to find OZ code, before we try to import and use it.
    • Run: forge remappings. Here you can see foundry making some assumptions for our environment:
    • But we will create custom remappings. For that create a file called remappings.txt in the folder and put this in there: @openzeppelin/=lib/openzeppelin-contracts/. NOTE: It looks like remappings while using solc. Maybe this is what is happening under the hood.
  • Step 4: Create a simple ERC721 contract in the src folder.
  • Step 5: Now, you can use OZ as you would in any hardhat project.

Thanks!