test_that("NRSI calculation works with dummy data", {
    # Create dummy data
    fish_data <- data.frame(
        trophic_level_f = rep(c("2-2.5", "3-3.5", "4-4.5"), each = 3),
        year = rep(2020, 9),
        region = rep("Test Region", 9),
        reef = rep("Test Reef", 9),
        protection = rep("Not Protected", 9),
        latitude = rep(20.5, 9),
        longitude = rep(-100.5, 9),
        depth2 = rep(10, 9),
        transect = rep(1:3, 3),
        biomass = c(100, 150, 200, 300, 350, 400, 50, 60, 70)
    )

    # Calculate NRSI
    result <- calculate_nrsi(fish_data)

    # Test structure
    expect_s3_class(result, "data.frame")
    expect_true("nrsi" %in% names(result))

    # Test calculation
    expect_true(all(result$nrsi >= -1 & result$nrsi <= 1))
})