feat: Add support for trunc()

NEWS.md

@@ -1,11 +1,14 @@
 # tidypolars (development)
 
+`tidypolars` requires `polars` >= 1.10.0.
+
 ## New features
 
 * Added support for the following functions:
 
   - `anyNA()` (#330)
   - `cummax()` (#323)
+  - `trunc()` (#343)
 
 * Added `decreasing` and `na.last` arguments support to `sort()` (@Yousa-Mirage, #328).
 

R/funs-default.R

@@ -491,6 +491,11 @@ pl_tanh <- function(x) {
   x$tanh()
 }
 
+pl_trunc <- function(x, ...) {
+  check_empty_dots(...)
+  x$truncate(decimals = 0)
+}
+
 pl_unique <- function(x, ...) {
   check_empty_dots(...)
   x$unique()

tests/testthat/_snaps/funs_default-lazy.md

@@ -8,6 +8,42 @@
       Caused by error:
       ! lengths don't match: unable to add a column of length 4 to a DataFrame of height 5
 
+# trunc() works
+
+    Code
+      current$collect()
+    Condition
+      Error in `current$collect()`:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
+# trunc() in tidypolars doesn't support Date/datetime
+
+    Code
+      current$collect()
+    Condition
+      Warning:
+      tidypolars doesn't know how to use some arguments of `trunc()`.
+      i The following argument(s) will be ignored: "units".
+      Error in `current$collect()`:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
+---
+
+    Code
+      current$collect()
+    Condition
+      Warning:
+      tidypolars doesn't know how to use some arguments of `trunc()`.
+      i The following argument(s) will be ignored: "units".
+      Error in `current$collect()`:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
 # sample() validates size
 
     Code

tests/testthat/_snaps/funs_default.md

@@ -10,6 +10,48 @@
       Caused by error:
       ! lengths don't match: unable to add a column of length 4 to a DataFrame of height 5
 
+# trunc() works
+
+    Code
+      mutate(test_pl, foo = trunc("a"))
+    Condition
+      Error in `.data$with_columns()`:
+      ! Evaluation failed in `$with_columns()`.
+      Caused by error:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
+# trunc() in tidypolars doesn't support Date/datetime
+
+    Code
+      mutate(test_pl, x = trunc(date, units = "secs"))
+    Condition
+      Warning:
+      tidypolars doesn't know how to use some arguments of `trunc()`.
+      i The following argument(s) will be ignored: "units".
+      Error in `.data$with_columns()`:
+      ! Evaluation failed in `$with_columns()`.
+      Caused by error:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
+---
+
+    Code
+      mutate(test_pl, x = trunc(datetime, units = "secs"))
+    Condition
+      Warning:
+      tidypolars doesn't know how to use some arguments of `trunc()`.
+      i The following argument(s) will be ignored: "units".
+      Error in `.data$with_columns()`:
+      ! Evaluation failed in `$with_columns()`.
+      Caused by error:
+      ! Evaluation failed in `$collect()`.
+      Caused by error:
+      ! truncation ('to_zero') can only be used on numeric types
+
 # sample() validates size
 
     Code

tests/testthat/test-funs_default-lazy.R

@@ -175,6 +175,39 @@ test_that("round() works", {
   )
 })
 
+test_that("trunc() works", {
+  test_df <- tibble(x = c(0.33, 0.5212, NA))
+  test_pl <- as_polars_lf(test_df)
+
+  expect_equal_lazy(
+    test_pl |> mutate(foo = trunc(x)),
+    test_df |> mutate(foo = trunc(x))
+  )
+  expect_both_error(
+    test_pl |> mutate(foo = trunc("a")),
+    test_df |> mutate(foo = trunc("a"))
+  )
+  expect_snapshot_lazy(
+    test_pl |> mutate(foo = trunc("a")),
+    error = TRUE
+  )
+})
+
+test_that("trunc() in tidypolars doesn't support Date/datetime", {
+  test_pl <- pl$LazyFrame(
+    date = as.Date("2020-01-01"),
+    datetime = as.POSIXct("2020-01-01")
+  )
+  expect_snapshot_lazy(
+    test_pl |> mutate(x = trunc(date, units = "secs")),
+    error = TRUE
+  )
+  expect_snapshot_lazy(
+    test_pl |> mutate(x = trunc(datetime, units = "secs")),
+    error = TRUE
+  )
+})
+
 test_that("sample() works with default size and n() size", {
   test_df <- tibble(x = 1:5)
   test_pl <- as_polars_lf(test_df)

tests/testthat/test-funs_default.R

@@ -171,6 +171,39 @@ test_that("round() works", {
   )
 })
 
+test_that("trunc() works", {
+  test_df <- tibble(x = c(0.33, 0.5212, NA))
+  test_pl <- as_polars_df(test_df)
+
+  expect_equal(
+    test_pl |> mutate(foo = trunc(x)),
+    test_df |> mutate(foo = trunc(x))
+  )
+  expect_both_error(
+    test_pl |> mutate(foo = trunc("a")),
+    test_df |> mutate(foo = trunc("a"))
+  )
+  expect_snapshot(
+    test_pl |> mutate(foo = trunc("a")),
+    error = TRUE
+  )
+})
+
+test_that("trunc() in tidypolars doesn't support Date/datetime", {
+  test_pl <- pl$DataFrame(
+    date = as.Date("2020-01-01"),
+    datetime = as.POSIXct("2020-01-01")
+  )
+  expect_snapshot(
+    test_pl |> mutate(x = trunc(date, units = "secs")),
+    error = TRUE
+  )
+  expect_snapshot(
+    test_pl |> mutate(x = trunc(datetime, units = "secs")),
+    error = TRUE
+  )
+})
+
 test_that("sample() works with default size and n() size", {
   test_df <- tibble(x = 1:5)
   test_pl <- as_polars_df(test_df)

vignettes/supported-functions.Rmd

@@ -81,6 +81,7 @@ out <- tribble(
   "`base`", "`tanh`",
   "`base`", "`tolower`",
   "`base`", "`toupper`",
+  "`base`", "`trunc`",
   "`base`", "`unique`",
   "`base`", "`which.min`",
   "`base`", "`which.max`",
@@ -190,6 +191,8 @@ out <- tribble(
         "In `tidypolars`, `na.last` must be explicitly supplied as `TRUE` or `FALSE`.",
       Package == "`base`" & Function == "`sample`" ~
         "`set.seed()` is not supported. Randomness is handled by Polars and does not use R's RNG state.",
+      Package == "`base`" & Function == "`trunc`" ~
+        "This only works with numeric data in `tidypolars`, while it works with other types (such as dates) in base R.",
       Package == "`lubridate`" & Function %in% c("`rollbackward`", "`rollback`", "`rollforward`") ~
         "While time zone handling should mimick the behaviour of `lubridate` in most cases, it is possible that Polars errors if rolling back/forward leads to am ambiguous datetime. It is also possible to have some differences in hours/minutes/seconds when converting between Polars and R.",
       Package == "`lubridate`" & Function == "`wday`" ~