testgl

# TestGL

A testing library which adds Java's TestNG's @DataProvider pattern to gleam.

## Usage

To setup TestGL, add the following to your `test/<package_name>_test.gleam` file

```gleam
import gleeunit
import testgl

pub fn main() -> Nil {
    testgl.main()
    gleeunit.main()
}
```

TestGL will search for public gleam functions in `.gleam` files in your `test/` directory that end with `_data_provider`
that return an `Tuple` of test data. Each data provider should have an associated function with the same name sans the
`_data_provider` suffix that accepts the inner type of the `Tuple` and performs a test. Here is an example:

```gleam
import gleam/string

pub fn string_upper_case_converts_lowercase_to_uppercase_data_provider() {
  #(#("hello", "HELLO"), #("from", "FROM"), #("testgl!", "TESTGL!"))
}

pub fn string_upper_case_converts_lowercase_to_uppercase(
  test_case: #(String, String),
) {
  assert string.uppercase(test_case.0) == test_case.1
}
```

TestGL will pick up these functions and transform them into the following 3 test cases in a generated file
`test/to_upper_should_convert_lowercase_to_uppercase.gleam`.

```gleam
import string_test.{
  string_upper_case_converts_lowercase_to_uppercase,
  string_upper_case_converts_lowercase_to_uppercase_data_provider,
}

pub fn string_upper_case_converts_lowercase_to_uppercase_0_test() {
  string_upper_case_converts_lowercase_to_uppercase_data_provider().0
  |> string_upper_case_converts_lowercase_to_uppercase
}

pub fn string_upper_case_converts_lowercase_to_uppercase_1_test() {
  string_upper_case_converts_lowercase_to_uppercase_data_provider().1
  |> string_upper_case_converts_lowercase_to_uppercase
}

pub fn string_upper_case_converts_lowercase_to_uppercase_2_test() {
  string_upper_case_converts_lowercase_to_uppercase_data_provider().2
  |> string_upper_case_converts_lowercase_to_uppercase
}
```