How do I write a test which has an array of structs ?

[allocgator]

How can I write the below Go code in V:

func TestUniquePaths(t *testing.T) {
    var testCases = []struct{
        description string
        rows, cols int
        ways int
    }{
        {
            "3 ways to go from the top left corner to the bottom right corner in a 3 x 2 grid",
            3, 2,
            3,
        },
        {
            "6 ways to go from the top left corner to the bottom right corner in a 3 x 3 grid",
            3, 3,
            6,
        },
        {
            "28 ways to go from the top left corner to the bottom right corner in a 3 x 7 grid",
            3, 7,
            28,
        },
        {
            "1 way to reach the bottom right corner in 1 x 1 grid; no moves need to be made",
            1, 1,
            1,
        },
        {
            "Over 190 million ways to go from the top left corner to the bottom right corner in a 23 x 12 grid",
            23, 12,
            193536720,
        },
    }

    for _, tc := range testCases {
        t.Run(tc.description, func(t *testing.T) {
            got := UniquePaths(tc.row, tc.cols)
            want := tc.ways

            if got != want {
                t.Errorf("Incorrect result: got %v, want %v", got, want)
            }
        })
    }
}

?

[gchumillas]

Not sure what you want to do. This is the way to write a test in V:

// tests are located in "path/to/anydir/filename_test.v"
// test functions starts with "test_" prefix
fn test_unique_paths() {
	items := [
		struct {
			description: '3 ways to go from the top left corner to the bottom right corner in a 3 x 2 grid'
			rows: 3
			cols: 2
			ways: 5
		}
		struct {
			description: '6 ways to go from the top left corner to the bottom right corner in a 3 x 3 grid'
			rows: 3
			cols: 3
			ways: 6
		}
	]

	for item in items {
		assert item.ways == item.rows + item.cols
	}
}

Here is the example: https://play.vlang.io/p/4f7525f3c8

[jorgeluismireles]

Optionally, you can add to assert line an string which will be printed as Message when assert failed. I changed ways:6 to ways:7 to make the test fail:

...
	assert item.ways == item.rows + item.cols, 'got ${item.ways} expected ${item.rows + item.cols}'
...

   > assert item.ways == item.rows + item.cols, 'got ${item.ways} expected ${item.rows + item.cols}'
     Left value (len: 1): `7`
    Right value (len: 1): `6`
        Message: got 7 expected 6

Though Left value and Right value messages are enough.

[allocgator]

Hi @gchumillas

I'm trying to write a table driven test in V.

Thanks to your post, I came up with the below, which is what I was looking for:

struct TestCase {
    description string
    rows int
    cols int
    ways int
}

fn test_unique_paths() {
    test_cases := [
        TestCase {
            "3 ways to go from the top left corner to the bottom right corner in a 3 x 2 grid",
            3, 2,
            3,
        },
        TestCase {
            "6 ways to go from the top left corner to the bottom right corner in a 3 x 3 grid",
            3, 3,
            6,
        },
        TestCase {
            "28 ways to go from the top left corner to the bottom right corner in a 3 x 7 grid",
            3, 7,
            28,
        },
        TestCase {
            "1 way to reach the bottom right corner in 1 x 1 grid; no moves need to be made",
            1, 1,
            1,
        },
        TestCase {
            "Over 190 million ways to go from the top left corner to the bottom right corner in a 23 x 12 grid",
            23, 12,
            193536720,
        },
    ]

    for tc in test_cases {
        print(tc.description + "\n")
        got := unique_paths(tc.rows, tc.cols)
        want := tc.ways

        assert(got == want)
    }
}