between supports Date/IDate with missing bounds

NEWS.md

@@ -54,6 +54,8 @@
 
 10. `setkey()`, `setindex()`, `CJ()`, and `setnames()` now prevent creating ambiguous keys from duplicated column names, and keyed joins now error on existing duplicated key columns rather than silently giving incorrect results, [#4888](https://github.com/Rdatatable/data.table/issues/4888) and [#4891](https://github.com/Rdatatable/data.table/issues/4891). Thanks @magerton and @MichaelChirico for the reports, and @ben-schwen for the fix.
 
+11. `between()` now supports `Date` and `IDate` bounds with default `NAbounds=TRUE`, avoiding errors like "Not yet implemented NAbounds=TRUE for this non-numeric and non-character type" when date bounds contain `NA`, [#7281](https://github.com/Rdatatable/data.table/issues/7281). Thanks @grcatlin for the report and fix, and @ben-schwen and @aitap for assistance.
+
 ### Notes
 
 1. {data.table} now depends on R 3.5.0 (2018).

R/between.R

@@ -5,6 +5,7 @@ between = function(x, lower, upper, incbounds=TRUE, NAbounds=TRUE, check=FALSE,
   if (is.logical(upper)) upper = as.integer(upper)   # typically NA (which is logical type)
   is.px = function(x) inherits(x, "POSIXct")
   is.i64 = function(x) inherits(x, "integer64")   # this is true for nanotime too
+  is.Date = function(x) inherits(x, "Date")
   # POSIXct special handling to auto coerce character
   if (is.px(x) && (is.character(lower) || is.character(upper))) {
     tz = attr(x, "tzone", exact=TRUE)
@@ -33,7 +34,14 @@ between = function(x, lower, upper, incbounds=TRUE, NAbounds=TRUE, check=FALSE,
     if (!is.i64(lower) && (is.integer(lower) || fitsInInt64(lower))) lower = bit64::as.integer64(lower)
     if (!is.i64(upper) && (is.integer(upper) || fitsInInt64(upper))) upper = bit64::as.integer64(upper)
   }
-  is.supported = function(x) is.numeric(x) || is.character(x) || is.px(x)
+  # Date special handling #7281
+  if (is.Date(x)) {
+    if (is.character(lower)) lower = tryCatch(as.Date(lower), error = function(e) stopf(
+      "The 'x' argument of the 'between' function is Date while '%s' was not, coercion to Date failed with: %s", 'lower', conditionMessage(e)))
+    if (is.character(upper)) upper = tryCatch(as.Date(upper), error = function(e) stopf(
+      "The 'x' argument of the 'between' function is Date while '%s' was not, coercion to Date failed with: %s", 'upper', conditionMessage(e)))
+  }
+  is.supported = function(x) is.numeric(x) || is.character(x) || is.px(x) || is.Date(x)
   if (is.supported(x) && is.supported(lower) && is.supported(upper)) {
     # faster parallelised version for int/double/character
     # Cbetween supports length(lower)==1 (recycled) and (from v1.12.0) length(lower)==length(x).

inst/tests/tests.Rraw

@@ -14688,6 +14688,28 @@ test(2038.34, between(1:10, -Inf, Inf),            rep(TRUE,10), output="between
 test(2038.35, between(as.double(1:10), -Inf, Inf), rep(TRUE,10), output="between parallel processing of double with closed bounds")
 options(old)
 
+# `between` supports Date/IDate with missing bounds, #7281
+x = data.table(
+  Date       = as.Date("2020-01-01") + 0:5,
+  Active     = c(TRUE, FALSE, TRUE, FALSE, TRUE, FALSE),
+  InRange    = c(TRUE, NA, FALSE, NA, TRUE, NA),
+  RangeBegin = as.Date("2020-01-01") + c(-1L, NA,  3L, NA,  3L, NA),
+  RangeEnd   = as.Date("2020-01-01") + c( 1L, NA,  4L, NA,  5L, NA)
+)
+x[Active == TRUE, InRange := c(TRUE, FALSE, TRUE)]
+x[InRange == TRUE, c("RangeBegin", "RangeEnd") := list(Date - 1L, Date + 1L)]
+x[InRange == FALSE, c("RangeBegin", "RangeEnd") := list(Date + 1L, Date + 2L)]
+test(2038.36, x[Active == TRUE & between(Date, RangeBegin, RangeEnd), Date], as.Date(c("2020-01-01", "2020-01-05")))
+# Date character bounds coercion
+test(2038.37, between(x$Date, "2020-01-02", "2020-01-04"), c(FALSE, TRUE, TRUE, TRUE, FALSE, FALSE))
+x[, c("Date", "RangeBegin", "RangeEnd") := lapply(.SD, as.IDate), .SDcols = c("Date", "RangeBegin", "RangeEnd")]
+test(2038.38, x[Active == TRUE & between(Date, RangeBegin, RangeEnd), Date], as.IDate(c("2020-01-01", "2020-01-05")))
+
+# errors name the bound that failed coercion
+x = as.Date("2020-01-01") + 0:4
+test(2038.39, between(x, "not-a-date", "2020-01-04"), error="Date while 'lower' was not, coercion to Date failed")
+test(2038.40, between(x, "2020-01-02", "not-a-date"), error="Date while 'upper' was not, coercion to Date failed")
+
 # between int64 support
 if (test_bit64) {
   as.i64 = bit64::as.integer64