🎉 Forces linter check before commit (starknet-edu#224)

* Adds pre-commit hook to force running linter

* Refactor pre-commit hoock

* Update to main + lint run

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Co-authored-by: Omar U. Espejel <espejelomar@gmail.com>

src/ch02-11-foundry-forge.md

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+# Foundry Forge: Testing 🚧
+
+[Starknet Foundry](https://github.com/foundry-rs/starknet-foundry) is a tool designed for testing and developing Starknet contracts. It is an adaptation of the Ethereum Foundry for Starknet, aiming to expedite the development process.
+
+The project consists of two primary components:
+
+- **Forge**: A testing tool specifically for Cairo contracts. This tool acts as a test runner and boasts features designed to enhance your testing process. Tests are written directly in Cairo, eliminating the need for other programming languages. Additionally, the Forge implementation uses Rust, mirroring Ethereum Foundry's choice of language.
+- **Cast**: This serves as a DevOps tool for StarkNet, initially supporting a series of commands to interface with StarkNet. In the future, Cast aims to offer deployment scripts for contracts and other DevOps functions.
+
+## Forge
+
+Merely deploying contracts is not the end game. Many tools have offered this capability in the past. Forge sets itself apart by hosting a Cairo VM instance, enabling the sequential execution of tests. It employs Scarb for contract compilation.
+
+To utilize Forge, define test functions and label them with test attributes. Users can either test standalone Cairo functions or integrate contracts, dispatchers, and test contract interactions on-chain.
+
+## `snForge` Command-Line Usage
+
+This section guides you through the Starknet Foundry `snforge` command-line tool. Learn how to set up a new project, compile the code, and execute tests.
+
+To start a new project with Starknet Foundry, use the `--init` command and replace `project_name` with your project's name.
+
+```shell
+snforge --init project_name
+```
+
+Once you've set up the project, inspect its layout:
+
+```shell
+cd project_name
+tree . -L 1
+```
+
+The project structure is as follows:
+
+```shell
+.
+├── README.md
+├── Scarb.toml
+├── src
+└── tests
+```
+
+- `src/` holds your contract source code.
+- `tests/` is the location of your test files.
+- `Scarb.toml` is for project and **`snforge`** configurations.
+
+Ensure the casm code generation is active in the `Scarb.toml` file:
+
+```shell
+# ...
+[[target.starknet-contract]]
+casm = true
+# ...
+```
+
+To run tests using `snforge`:
+
+```shell
+snforge
+
+Collected 2 test(s) from the `test_name` package
+Running 0 test(s) from `src/`
+Running 2 test(s) from `tests/`
+[PASS] tests::test_contract::test_increase_balance
+[PASS] tests::test_contract::test_cannot_increase_balance_with_zero_value
+Tests: 2 passed, 0 failed, 0 skipped
+```
+
+## Integrating `snforge` with Existing Scarb Projects
+
+For those with an established Scarb project who wish to incorporate `snforge`, ensure the `snforge_std package` is declared as a dependency. Insert the line below in the [dependencies] section of your `Scarb.toml`:
+
+```shell
+# ...
+[dependencies]
+snforge_std = { git = "https://github.com/foundry-rs/starknet-foundry.git", tag = "[VERSION]" }
+```
+
+Ensure the tag version corresponds with your `snforge` version. To verify your `snforge` version:
+
+```sh
+snforge --version
+```
+
+Or, add this dependency using the `scarb` command:
+
+```shell
+scarb add snforge_std --git https://github.com/foundry-rs/starknet-foundry.git --tag VERSION
+```
+
+With these steps, your existing Scarb project is now **`snforge`**-ready.
+
+## Testing with `snforge`
+
+Utilize Starknet Foundry's `snforge` command to efficiently run tests.
+
+### Executing Tests
+
+Navigate to the package directory and issue this command to run tests:
+
+```shell
+snforge
+```
+
+Sample output might resemble:
+
+```shell
+Collected 3 test(s) from `package_name` package
+Running 3 test(s) from `src/`
+[PASS] package_name::executing
+[PASS] package_name::calling
+[PASS] package_name::calling_another
+Tests: 3 passed, 0 failed, 0 skipped
+```
+
+### Filter Tests
+
+Run specific tests using a filter string after the `snforge` command. Tests matching the filter based on their absolute module tree path will be executed:
+
+```shell
+$ snforge calling
+```
+
+### Run a Specific Test
+
+Use the `--exact` flag and a fully qualified test name to run a particular test:
+
+```shell
+snforge package_name::calling --exact
+```
+
+### Stop After First Test Failure
+
+To stop after the first test failure, add the `--exit-first` flag to the `snforge` command:
+
+```shell
+snforge --exit-first
+```
+
+## Basic Example
+
+The example provided below demonstrates how to test a Starknet contract using `snforge`.
+
+```rust
+#[starknet::interface]
+trait IHelloStarknet<TContractState> {
+    fn increase_balance(ref self: TContractState, amount: felt252);
+    fn get_balance(self: @TContractState) -> felt252;
+}
+
+#[starknet::contract]
+mod HelloStarknet {
+    #[storage]
+    struct Storage {
+        balance: felt252,
+    }
+
+    #[external(v0)]
+    impl HelloStarknetImpl of super::IHelloStarknet<ContractState> {
+        // Increases the balance by the specified amount.
+        fn increase_balance(ref self: ContractState, amount: felt252) {
+            self.balance.write(self.balance.read() + amount);
+        }
+
+        // Returns the balance.
+        fn get_balance(self: @ContractState) -> felt252 {
+            self.balance.read()
+        }
+    }
+}
+```
+
+Remember, the identifier following `mod` signifies the contract name. Here, the contract name is `HelloStarknet`.
+
+### Craft the Test
+
+Below is a test for the **`HelloStarknet`** contract. This test deploys **`HelloStarknet`** and interacts with its functions:
+
+```rust
+use snforge_std::{ declare, ContractClassTrait };
+
+#[test]
+fn call_and_invoke() {
+    // Declare and deploy the contract
+    let contract = declare('HelloStarknet');
+    let contract_address = contract.deploy(@ArrayTrait::new()).unwrap();
+
+    // Instantiate a Dispatcher object for contract interactions
+    let dispatcher = IHelloStarknetDispatcher { contract_address };
+
+    // Invoke a contract's view function
+    let balance = dispatcher.get_balance();
+    assert(balance == 0, 'balance == 0');
+
+    // Invoke another function to modify the storage state
+    dispatcher.increase_balance(100);
+
+    // Validate the transaction's effect
+    let balance = dispatcher.get_balance();
+    assert(balance == 100, 'balance == 100');
+}
+```
+
+To run the test, execute the `snforge` command. The expected output is:
+
+```shell
+Collected 1 test(s) from using_dispatchers package
+Running 1 test(s) from src/
+[PASS] using_dispatchers::call_and_invoke
+Tests: 1 passed, 0 failed, 0 skipped
+```