Add unit tests for functions

tests/testthat/test-filtering.R

@@ -0,0 +1,38 @@
+library(testthat)
+
+test_that("dob2age correctly calculates age from Date of Birth", {
+  test_dataset <- data.frame(
+    date_of_birth = as.Date(c("1990-01-15", "1985-05-10", "2000-12-30"))
+  )
+
+  arrow::write_dataset(test_dataset, path = "test_dob2age")
+
+  dob2age("test_dob2age", "date_of_birth", input = ".", partitions = NULL)
+
+  modified_dataset <- arrow::open_dataset("test_dob2age")
+
+  expect_true("age" %in% names(modified_dataset))
+  expect_equal((modified_dataset %>% collect %>% pull(age)), c(33, 38, 23))
+
+  unlink("test_dob2age/part-0.parquet")
+})
+
+test_that("drop_cols_datasets correctly drops specified columns", {
+  test_dataset <- data.frame(
+    column1 = c(1, 2, 3),
+    column2 = c("A", "B", "C"),
+    column3 = c(0.1, 0.2, 0.3)
+  )
+
+  arrow::write_dataset(test_dataset, path = "test_drop_cols")
+
+  columns_to_drop <- c("column1", "column2")
+
+  drop_cols_datasets("test_drop_cols", columns = columns_to_drop, input = ".", output = ".")
+
+  modified_dataset <- arrow::open_dataset("test_drop_cols")
+
+  expect_true(all(!names(modified_dataset) %in% columns_to_drop))
+
+  unlink("test_drop_cols/part-0.parquet")
+})