diff --git a/NEWS.md b/NEWS.md
index b0717d73c..dfdd8db75 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -22,6 +22,7 @@
   For now, `future = FALSE` can be replaced by `compat_level = FALSE` (#1183).
 - In `$scan_parquet()` and `$read_parquet()`, the default value of
   `hive_partitioning` is now `NULL` (#1189).
+- In `$dt$epoch()`, the argument `tu` is renamed to `time_unit` (#1196). 
 
 ### New features
 
diff --git a/R/expr__datetime.R b/R/expr__datetime.R
index 6d429c141..ddaba29a9 100644
--- a/R/expr__datetime.R
+++ b/R/expr__datetime.R
@@ -482,37 +482,30 @@ ExprDT_nanosecond = function() {
 }
 
 
-# TODO: update the argument name and examples
 #' Epoch
-#' @description
+#'
 #' Get the time passed since the Unix EPOCH in the give time unit.
 #'
-#' @param tu string option either 'ns', 'us', 'ms', 's' or  'd'
-#' @details ns and perhaps us will exceed integerish limit if returning to
-#' R as flaot64/double.
-#' @return Expr of epoch as UInt32
-#' @keywords ExprDT
-#' @aliases (Expr)$dt$epoch
-#' @examples
-#' as_polars_series(as.Date("2022-1-1"))$dt$epoch("ns")
-#' as_polars_series(as.Date("2022-1-1"))$dt$epoch("ms")
-#' as_polars_series(as.Date("2022-1-1"))$dt$epoch("s")
-#' as_polars_series(as.Date("2022-1-1"))$dt$epoch("d")
-ExprDT_epoch = function(tu = c("us", "ns", "ms", "s", "d")) {
-  tu = tu[1]
+#' @param time_unit Time unit, one of `"ns"`, `"us"`, `"ms"`, `"s"` or  `"d"`.
+#'
+#' @return Expr with datatype Int64
+#' @examples
+#' df = pl$DataFrame(date = pl$date_range(as.Date("2001-1-1"), as.Date("2001-1-3")))
+#'
+#' df$with_columns(
+#'   epoch_ns = pl$col("date")$dt$epoch(),
+#'   epoch_s = pl$col("date")$dt$epoch(time_unit = "s")
+#' )
+ExprDT_epoch = function(time_unit = "us") {
+  time_unit = match.arg(time_unit, choices = c("us", "ns", "ms", "s", "d"))
   uw = \(res) unwrap(res, "in $dt$epoch:")
 
-  # experimental rust-like error handling on R side for the fun of it, sorry
-  # jokes aside here the use case is to tie various rust functions together
-  # and add context to the error messages
-  pcase(
-    !is_string(tu), Err("tu must be a string") |> uw(),
-    tu %in% c("ms", "us", "ns"), .pr$Expr$dt_timestamp(self, tu) |> uw(),
-    tu == "s", .pr$Expr$dt_epoch_seconds(self),
-    tu == "d", self$cast(pl$Date)$cast(pl$Int32),
-    or_else = Err(
-      paste("tu must be one of 'ns', 'us', 'ms', 's', 'd', got", str_string(tu))
-    ) |> uw()
+  switch(time_unit,
+    "ms" = ,
+    "us" = ,
+    "ns" = .pr$Expr$dt_timestamp(self, time_unit) |> uw(),
+    "s" = .pr$Expr$dt_epoch_seconds(self),
+    "d" = self$cast(pl$Date)$cast(pl$Int32)
   )
 }
 
diff --git a/man/DataFrame_class.Rd b/man/DataFrame_class.Rd
index 3bc8cc028..5b241516a 100644
--- a/man/DataFrame_class.Rd
+++ b/man/DataFrame_class.Rd
@@ -116,9 +116,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/DataFrame_to_data_frame.Rd b/man/DataFrame_to_data_frame.Rd
index 1fc135a84..04401a24c 100644
--- a/man/DataFrame_to_data_frame.Rd
+++ b/man/DataFrame_to_data_frame.Rd
@@ -59,9 +59,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/DataFrame_to_list.Rd b/man/DataFrame_to_list.Rd
index cf55bf3d2..766d7d1d0 100644
--- a/man/DataFrame_to_list.Rd
+++ b/man/DataFrame_to_list.Rd
@@ -69,9 +69,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/ExprDT_epoch.Rd b/man/ExprDT_epoch.Rd
index 1fe21427c..2238014c1 100644
--- a/man/ExprDT_epoch.Rd
+++ b/man/ExprDT_epoch.Rd
@@ -2,28 +2,24 @@
 % Please edit documentation in R/expr__datetime.R
 \name{ExprDT_epoch}
 \alias{ExprDT_epoch}
-\alias{(Expr)$dt$epoch}
 \title{Epoch}
 \usage{
-ExprDT_epoch(tu = c("us", "ns", "ms", "s", "d"))
+ExprDT_epoch(time_unit = "us")
 }
 \arguments{
-\item{tu}{string option either 'ns', 'us', 'ms', 's' or  'd'}
+\item{time_unit}{Time unit, one of \code{"ns"}, \code{"us"}, \code{"ms"}, \code{"s"} or  \code{"d"}.}
 }
 \value{
-Expr of epoch as UInt32
+Expr with datatype Int64
 }
 \description{
 Get the time passed since the Unix EPOCH in the give time unit.
 }
-\details{
-ns and perhaps us will exceed integerish limit if returning to
-R as flaot64/double.
-}
 \examples{
-as_polars_series(as.Date("2022-1-1"))$dt$epoch("ns")
-as_polars_series(as.Date("2022-1-1"))$dt$epoch("ms")
-as_polars_series(as.Date("2022-1-1"))$dt$epoch("s")
-as_polars_series(as.Date("2022-1-1"))$dt$epoch("d")
+df = pl$DataFrame(date = pl$date_range(as.Date("2001-1-1"), as.Date("2001-1-3")))
+
+df$with_columns(
+  epoch_ns = pl$col("date")$dt$epoch(),
+  epoch_s = pl$col("date")$dt$epoch(time_unit = "s")
+)
 }
-\keyword{ExprDT}
diff --git a/man/LazyFrame_class.Rd b/man/LazyFrame_class.Rd
index 3cf20de68..37b1144fb 100644
--- a/man/LazyFrame_class.Rd
+++ b/man/LazyFrame_class.Rd
@@ -86,9 +86,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/S3_as.data.frame.Rd b/man/S3_as.data.frame.Rd
index 9223cc562..299859831 100644
--- a/man/S3_as.data.frame.Rd
+++ b/man/S3_as.data.frame.Rd
@@ -110,9 +110,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/S3_as.vector.Rd b/man/S3_as.vector.Rd
index 850878e85..dea4207d7 100644
--- a/man/S3_as.vector.Rd
+++ b/man/S3_as.vector.Rd
@@ -46,9 +46,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/Series_class.Rd b/man/Series_class.Rd
index 40185d9dd..bfb719b7d 100644
--- a/man/Series_class.Rd
+++ b/man/Series_class.Rd
@@ -143,9 +143,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/man/Series_to_r.Rd b/man/Series_to_r.Rd
index 831bb49de..d77ee5fae 100644
--- a/man/Series_to_r.Rd
+++ b/man/Series_to_r.Rd
@@ -62,9 +62,7 @@ withr::with_timezone(
   \}
 )
 #> <error: in to_r: ComputeError(ErrString("datetime '2020-03-08 02:00:00' is non-existent in time zone 'America/New_York'. You may be able to use `non_existent='null'` to return `null` in this case.")) When calling: devtools::document()>
-}\if{html}{\out{</div>}}
 
-\if{html}{\out{<div class="sourceCode r">}}\preformatted{
 withr::with_timezone(
   "America/New_York",
   \{
diff --git a/tests/testthat/test-datatype.R b/tests/testthat/test-datatype.R
index c14065665..3066ce4f2 100644
--- a/tests/testthat/test-datatype.R
+++ b/tests/testthat/test-datatype.R
@@ -42,7 +42,7 @@ test_that("POSIXct data conversion", {
     pl$lit("2022-01-01")$str$strptime(pl$Datetime(), "%F")$to_r(),
     as.POSIXct("2022-01-01")
   )
-  # TODO: infer timezone from string, change the arugment name from `tz`
+  # TODO: infer timezone from string
   expect_true(
     as_polars_series("2022-01-01 UTC")$str$strptime(pl$Datetime(time_zone = "UTC"), "%F %Z")$eq(
       as_polars_series(as.POSIXct("2022-01-01", tz = "UTC"))
@@ -56,7 +56,7 @@ test_that("POSIXct data conversion", {
         pl$lit("2022-01-01")$str$strptime(pl$Datetime(), "%F")$to_r(),
         as.POSIXct("2022-01-01")
       )
-      # TODO: infer timezone from string, change the arugment name from `tz`
+      # TODO: infer timezone from string
       expect_true(
         as_polars_series("2022-01-01 UTC")$str$strptime(pl$Datetime(time_zone = "UTC"), "%F %Z")$eq(
           as_polars_series(as.POSIXct("2022-01-01", tz = "UTC"))
diff --git a/tests/testthat/test-expr_datetime.R b/tests/testthat/test-expr_datetime.R
index d06cfc883..7d5df2711 100644
--- a/tests/testthat/test-expr_datetime.R
+++ b/tests/testthat/test-expr_datetime.R
@@ -460,11 +460,11 @@ test_that("dt$epoch", {
 
   expect_grepl_error(
     as_polars_series(as.Date("2022-1-1"))$dt$epoch("bob"),
-    "epoch: tu must be one of 'ns', 'us', 'ms', 's', 'd'"
+    "should be one of"
   )
   expect_grepl_error(
     as_polars_series(as.Date("2022-1-1"))$dt$epoch(42),
-    "epoch: tu must be a string"
+    "must be NULL or a character vector"
   )
 })
 
@@ -574,8 +574,8 @@ test_that("$convert_time_zone() works", {
   )
   df_casts = df_time$with_columns(
     pl$col("date")
-      $dt$convert_time_zone("Europe/London")
-      $alias("London")
+    $dt$convert_time_zone("Europe/London")
+    $alias("London")
   )
 
   orig_r = as.POSIXct(
diff --git a/tests/testthat/test-lazy_functions.R b/tests/testthat/test-lazy_functions.R
index cacd90345..cdf8e2a02 100644
--- a/tests/testthat/test-lazy_functions.R
+++ b/tests/testthat/test-lazy_functions.R
@@ -582,11 +582,12 @@ test_that("pl$int_range() works", {
   )
 
   # custom data type
-  # TODO: this works with any dtype, how can I test this?
-  # expect_true(all.equal(
-  #   as_polars_series(pl$int_range(0, 3, dtype = pl$Int16))$dtype,
-  #   pl$Float32
-  # ))
+  expect_true(
+    as_polars_series(pl$int_range(0, 3, dtype = pl$Int16))$dtype == pl$Int16
+  )
+  expect_false(
+    as_polars_series(pl$int_range(0, 3, dtype = pl$Int16))$dtype == pl$Int32
+  )
 
   expect_grepl_error(
     pl$int_range(0, 3, dtype = pl$String) |> as_polars_series(),
@@ -624,13 +625,16 @@ test_that("pl$int_ranges() works", {
     list(int_range = list(c(1, 2), c(-1, 0, 1)))
   )
 
-  # TODO: this works with any dtype, how can I test this?
-  # expect_true(
-  #   all.equal(
-  #     df$select(int_range = pl$int_ranges("start", "end", dtype = pl$Int16))$schema,
-  #     list(int_range = pl$List(pl$Int16))
-  #   )
-  # )
+  expect_true(
+    df$select(int_range = pl$int_ranges("start", "end", dtype = pl$Int16))$
+      schema$
+      int_range == pl$List(pl$Int16)
+  )
+  expect_false(
+    df$select(int_range = pl$int_ranges("start", "end", dtype = pl$Int16))$
+      schema$
+      int_range == pl$List(pl$String)
+  )
 
   expect_grepl_error(
     df$select(int_range = pl$int_ranges("start", "end", dtype = pl$String)),