
library(testthat)

source("user_code.R")
test_that("output is character vector of same length as input", {
  input <- c("2023-03-05", "2023-06-15", "2023-09-30")
  output <- convert_and_format_dates(input)
  expect_equal(length(output), length(input),
               info = "Output vector should have the same length as input.")
  expect_equal(typeof(output), "character",
               info = "Output should be a character vector.")
})

test_that("output is formatted as 'Month Day, Year'", {
  input <- c("2023-03-05", "2023-06-15", "2023-09-30")
  output <- convert_and_format_dates(input)
  expect_equal(output[1], "March 5, 2023",
               info = "First date should be formatted as 'March 5, 2023'.")
  expect_equal(output[2], "June 15, 2023",
               info = "Second date should be formatted as 'June 15, 2023'.")
  expect_equal(output[3], "September 30, 2023",
               info = "Third date should be formatted as 'September 30, 2023'.")
})

test_that("handles multiple date strings", {
  input <- c("2022-01-01", "2022-12-31", "2023-07-04")
  output <- convert_and_format_dates(input)
  expect_equal(output, c("January 1, 2022", "December 31, 2022", "July 4, 2023"),
               info = "Should correctly process multiple dates including different years.")
})

test_that("handles dates at beginning and end of year", {
  input <- c("2022-01-01", "2022-12-31")
  output <- convert_and_format_dates(input)
  expect_equal(output[1], "January 1, 2022",
               info = "Should correctly format beginning of year date.")
  expect_equal(output[2], "December 31, 2022",
               info = "Should correctly format end of year date.")
})

test_main.R

Master the essentials of handling text, dates, and files in R. This course guides you through string manipulation, regular expressions, date-time operations, and file I/O, with engaging explanations and practical challenges for beginners.

Learn to work with text data in R, from basic string operations to cleaning messy data using regular expressions.

Master handling dates and times in R, from parsing and formatting to performing calculations and managing time zones.

Explore the foundations of data cleaning and quality assurance in R. Each chapter introduces a core concept, followed by a hands-on challenge to reinforce your learning.

Challenge: Convert and Format Dates

Solution