tests/testthat/test-recipe_scale_center.R

In DSCI-310/DSCI-310-Group-11-package: Data Preprocessing for Exploratory Data Analysis

library(testthat)

test_that("`recipe_scale_center` should return a `tidymodels` recipe,
          given a data frame and formula", {
            expect_s3_class(
              recipe_scale_center(one_predictor_df, one_predictor_formula),
              recipe_type
            )
            expect_s3_class(
              recipe_scale_center(two_predictors_df, two_predictors_formula),
              recipe_type
            )
            expect_s3_class(
              recipe_scale_center(three_predictors_df, three_predictors_formula),
              recipe_type
            )
          })

test_that("`recipe_scale_center` should throw an error if the `formula` argument
          is not formatted `target ~ predictor`", {
            expect_error(recipe_scale_center(one_predictor_df, not_formula))
            expect_error(recipe_scale_center(two_predictors_df, not_formula))
            expect_error(recipe_scale_center(three_predictors_df, not_formula))
            expect_error(recipe_scale_center(two_predictors_df, one_predictor_df))
          })

test_that("`recipe_scale_center` should throw an error if the `data` argument
          is not a data frame", {
            expect_error(recipe_scale_center(not_df, one_predictor_formula))
            expect_error(recipe_scale_center(not_df, two_predictors_formula))
            expect_error(recipe_scale_center(not_df, three_predictors_formula))
          })

test_that("`recipe_scale_center` should throw an error if the given data frame
          does not have any observations (ie: no columns)", {
            expect_error(recipe_scale_center(empty_df, one_predictor_formula))
            expect_error(recipe_scale_center(no_col_has_rows_df, two_predictors_formula))
          })

test_that("`recipe_scale_center` should throw an error if the `data` argument
          is not a data frame and `formula` is not formatting as
          `target ~ predictor`", {
            expect_error(recipe_scale_center(not_df, not_formula))
            expect_error(recipe_scale_center(bin, not_formula))
          })