tests/testthat/test-test-trends.R

In bcgov/wqbc: Tidy Water Quality Data and Calculate Thresholds for British Columbia

# Copyright 2016 Province of British Columbia
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and limitations under the License.

context("test-trends")

test_that("test_trends", {
  trend1 <- test_trends(wqbc::yuepilon)
  # test output structure
  expect_identical(nrow(trend1), 4L)
  expect_identical(ncol(trend1), 9L)
  expect_is(trend1$slope, "numeric")
  expect_is(trend1$Month, "character")
  # test values
  expect_equal(trend1$slope[1], c(Year = 0.0135076018042468))
  # test breaks
  trend2 <- test_trends(wqbc::yuepilon, breaks = c(1, 4, 12))
  expect_identical(nrow(trend2), 4L * 3L)
  expect_identical(ncol(trend2), 9L)
  expect_identical(sum(is.na(trend2$slope)), 4L * 2L)
  expect_lt(abs(trend1$slope[1] - trend2$slope[1]), 1e-6)
})

test_that("test_trends provides useful error messages", {
  expect_error(test_trends(wqbc::dummy), class = "chk_error")
})

test_that("summarise_for_trends", {
  data(yuepilon)
  data <- yuepilon[yuepilon$Station == "02EA005", ]
  trend <- test_trends(data, messages = TRUE)
  datasum <- summarise_for_trends(data)
  expect_is(datasum, "tbl_df")
  expect_identical(colnames(datasum), c("Station", "Variable", "Units", "Year", "Month", "Value"))
  expect_equal(datasum$Year, 1949:1999)
  expect_equal(datasum$Value[1:3], c(5.6496712529496, 5.44526029351639, 7.28700275094542))
})