[Fix #719] Print negative durations with leading -

R/durations.r

@@ -82,11 +82,12 @@ compute_estimate <- function (secs, unit = "second") {
   if (is.null(next_unit))
     return(.readable_duration(secs, "year"))
   out <- character(length(secs))
-  tt <- secs < SECONDS_IN_ONE[[next_unit]]
+  tt <- abs(secs) < SECONDS_IN_ONE[[next_unit]]
   if (any(tt))
     out[tt] <- .readable_duration(secs[tt], unit)
   wnext <- which(!tt)
-  out[wnext] <- compute_estimate(secs[wnext], next_unit)
+  if (length(wnext))
+    out[wnext] <- compute_estimate(secs[wnext], next_unit)
   out
 }
 
@@ -101,10 +102,10 @@ setMethod("show", signature(object = "Duration"), function(object) {
 
 #' @export
 format.Duration <- function(x, ...) {
-  out <- vector("character", length(x@.Data))
+  out <- character(length(x@.Data))
   nnas <- !is.na(x@.Data)
-  out[nnas] <- compute_estimate(abs(x@.Data[nnas]))
-  out[!nnas] <- NA
+  out[nnas] <- compute_estimate(x@.Data[nnas])
+  out[!nnas] <- NA_character_
   out
 }
 

tests/testthat/test-am-pm.R

@@ -10,6 +10,5 @@ test_that("am and pm handle various classes of date-time object", {
   x <- as.POSIXct(c("2009-08-03 13:01:59", "2008-08-03 10:01:59"), tz = "UTC")
   expect_equal(am(x), c(FALSE, TRUE))
   expect_equal(am(as.POSIXlt(x)), c(FALSE, TRUE))
-
   expect_equal(am(as.Date(x)), c(TRUE, TRUE))
 })

tests/testthat/test-durations.R

@@ -173,10 +173,12 @@ test_that("is.duration works as expected", {
   expect_false(is.duration(interval(lt_time, ct_time)))
 })
 
-test_that("format.Duration correctly displays durations with an NA", {
-  dur <- duration(seconds = c(5, NA))
-
-  expect_equivalent(format(dur), c("5s", NA))
+test_that("format.Duration works as expected", {
+  dur <- duration(seconds = c(5, NA, 10, -10, 1000, -1000))
+  expect_equivalent(format(dur),
+                    c("5s", NA, "10s", "-10s",
+                      "1000s (~16.67 minutes)",
+                      "-1000s (~-16.67 minutes)"))
 })
 
 test_that("summary.Duration creates useful summary", {