Additional correlation/lag tests

Author: capnrefsmmat

R-packages/covidcast/tests/testthat/test-cor.R

@@ -29,3 +29,57 @@ test_that("simple correlations", {
                              by = "geo_value"),
                expected)
 })
+
+test_that("basic lagged correlations", {
+  foo <- data.frame(
+    time_value = as.Date(c("2020-01-01", "2020-01-02",
+                           "2020-01-03", "2020-01-04")),
+    geo_value = "pa",
+    issue = 1,
+    value = c(1, 2, 1, 2)
+  )
+
+  bar <- data.frame(
+    time_value = as.Date(c("2020-01-01", "2020-01-02",
+                           "2020-01-03", "2020-01-04")),
+    geo_value = "pa",
+    issue = 1,
+    value = c(2, 1, 2, 1)
+  )
+
+  expected <- tibble(
+    geo_value = "pa",
+    value = 1
+  )
+  expect_equal(covidcast_cor(foo, bar, dt_x = 1),
+               expected)
+  expect_equal(covidcast_cor(foo, bar, dt_y = 1),
+               expected)
+})
+
+test_that("lags are in correct direction", {
+  foo <- data.frame(
+    time_value = seq.Date(as.Date("2020-01-01"), as.Date("2020-01-10"),
+                          "day"),
+    geo_value = "pa",
+    issue = 1,
+    value = 1:10
+  )
+
+  bar <- data.frame(
+    time_value = seq.Date(as.Date("2020-01-01"), as.Date("2020-01-10"),
+                          "day"),
+    geo_value = "pa",
+    issue = 1,
+    value = c(rep(0, 5), 1:5)
+  )
+
+  expected <- tibble(
+    geo_value = "pa",
+    value = 1
+  )
+  expect_equal(covidcast_cor(foo, bar, dt_x = -4),
+               expected)
+  expect_equal(covidcast_cor(foo, bar, dt_y = 4),
+               expected)
+})