add Ops.hms and tests for {+-*/} {integer,numeric} and {+-} Date

.gitignore

@@ -5,3 +5,4 @@
 CRAN-RELEASE
 docs
 .vscode
+.idea

NAMESPACE

@@ -1,8 +1,11 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method("+",Date)
+S3method("-",Date)
 S3method("[<-",hms)
 S3method("[[",hms)
 S3method("units<-",hms)
+S3method(Ops,hms)
 S3method(as.POSIXct,hms)
 S3method(as.POSIXlt,hms)
 S3method(as.character,hms)

R/generics.R

@@ -0,0 +1,20 @@
+#' @export
+Ops.hms <- function(e1, e2) {
+  if (.Generic == "+" && (inherits(e1, "Date") || inherits(e2, "Date"))) {
+    return(base::`+.Date`(e1, e2))
+  } else if (.Generic == "-" && inherits(e1, "Date")) {
+    return(base::`-.Date`(e1, e2))
+  }
+  res <- NextMethod(.Generic)
+  if (inherits(res, "difftime")) {
+    as_hms(res)
+  } else {
+    res
+  }
+}
+
+#' @export
+`+.Date` <- Ops.hms
+
+#' @export
+`-.Date` <- Ops.hms

tests/testthat/test-generics.R

@@ -0,0 +1,65 @@
+test_that("generic operations work as intended", {
+  # Test that all binary operations involving hms and one of Date, POSIXct, POSIXlt, difftime, hms, numeric, integer
+  # behave the same as the operation would with a difftime of the same length, except for difftime results, wich should
+  # be hms of the same value instead.
+
+  hms_test_vec <- new_hms(c(0.0, NA_real_, 10.0))
+
+  # hms {+-*/} integer
+  expect_equal(hms_test_vec + 1L, new_hms(c(1.0, NA_real_, 11.0)))
+  expect_equal(hms_test_vec + (1L:3L), new_hms(c(1.0, NA_real_, 13.0)))
+  expect_equal(1L + hms_test_vec, new_hms(c(1.0, NA_real_, 11.0)))
+  expect_equal((1L:3L) + hms_test_vec, new_hms(c(1.0, NA_real_, 13.0)))
+
+  expect_equal(hms_test_vec - 1L, new_hms(c(-1.0, NA_real_, 9.0)))
+  expect_equal(hms_test_vec - (1L:3L), new_hms(c(-1.0, NA_real_, 7.0)))
+  expect_equal(1L - hms_test_vec, new_hms(c(1.0, NA_real_, -9.0)))
+  expect_equal((1L:3L) - hms_test_vec, new_hms(c(1.0, NA_real_, -7.0)))
+
+  expect_equal(hms_test_vec * 2L, new_hms(c(0.0, NA_real_, 20.0)))
+  expect_equal(hms_test_vec * (1L:3L), new_hms(c(0.0, NA_real_, 30.0)))
+  expect_equal(2L * hms_test_vec, new_hms(c(0.0, NA_real_, 20.0)))
+  expect_equal((1L:3L) * hms_test_vec, new_hms(c(0.0, NA_real_, 30.0)))
+
+  expect_equal(hms_test_vec / 2L, new_hms(c(0.0, NA_real_, 5.0)))
+  expect_equal(hms_test_vec / c(1L, 2L, 4L), new_hms(c(0.0, NA_real_, 2.5)))
+  expect_error(1L / hms_test_vec, "second argument of / cannot be a \"difftime\" object")
+
+  # hms {+-*/} numeric
+  expect_equal(hms_test_vec + 1.0, new_hms(c(1.0, NA_real_, 11.0)))
+  expect_equal(hms_test_vec + (1.0:3.0), new_hms(c(1.0, NA_real_, 13.0)))
+  expect_equal(1.0 + hms_test_vec, new_hms(c(1.0, NA_real_, 11.0)))
+  expect_equal((1.0:3.0) + hms_test_vec, new_hms(c(1.0, NA_real_, 13.0)))
+
+  expect_equal(hms_test_vec - 1.0, new_hms(c(-1.0, NA_real_, 9.0)))
+  expect_equal(hms_test_vec - (1.0:3.0), new_hms(c(-1.0, NA_real_, 7.0)))
+  expect_equal(1.0 - hms_test_vec, new_hms(c(1.0, NA_real_, -9.0)))
+  expect_equal((1.0:3.0) - hms_test_vec, new_hms(c(1.0, NA_real_, -7.0)))
+
+  expect_equal(hms_test_vec * 2.0, new_hms(c(0.0, NA_real_, 20.0)))
+  expect_equal(hms_test_vec * (1.0:3.0), new_hms(c(0.0, NA_real_, 30.0)))
+  expect_equal(2.0 * hms_test_vec, new_hms(c(0.0, NA_real_, 20.0)))
+  expect_equal((1.0:3.0) * hms_test_vec, new_hms(c(0.0, NA_real_, 30.0)))
+
+  expect_equal(hms_test_vec / 2.0, new_hms(c(0.0, NA_real_, 5.0)))
+  expect_equal(hms_test_vec / c(1.0, 2.0, 4.0), new_hms(c(0.0, NA_real_, 2.5)))
+  expect_error(1.0 / hms_test_vec, "second argument of / cannot be a \"difftime\" object")
+
+  # hms {+-} Date
+  # 86400.0 secs = 24 hours
+  hms_test_vec <- new_hms(86400.0 * c(1.0, NA_real_, 10.0))
+  difftime_test_vec <- as.difftime(86400.0 * c(1.0, NA_real_, 10.0), units = "secs")
+  date_vec <- as.Date(c("1970-01-01", NA_character_, "2023-08-21"))
+
+  expect_equal(hms_test_vec + date_vec, difftime_test_vec + date_vec)
+  expect_equal(date_vec + hms_test_vec, date_vec + difftime_test_vec)
+
+  # Can't reproduce this warning because we forced compatibility
+  hms_result <- hms_test_vec - date_vec
+  expect_warning({
+    difftime_result <- as_hms(difftime_test_vec - date_vec)
+  }, regexp = "Incompatible methods \\(\"Ops.difftime\", \"-.Date\") for \"-\"")
+  expect_equal(hms_result, difftime_result)
+
+  expect_equal(date_vec - hms_test_vec, date_vec - difftime_test_vec)
+})