From 035f4a92339d7cfeed562fa3904a735238a29643 Mon Sep 17 00:00:00 2001
From: Maximilian Girlich <maximilian.girlich@metoda.com>
Date: Tue, 7 Nov 2023 14:13:00 +0100
Subject: [PATCH] Add `runif(n())` translation (#526)

---
 DESCRIPTION                 | 4 ++--
 NEWS.md                     | 3 +++
 R/dplyr.R                   | 6 +++++-
 tests/testthat/test-dplyr.R | 7 +++++++
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/DESCRIPTION b/DESCRIPTION
index e890c851..927be4a1 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -40,8 +40,8 @@ Imports:
 Suggests: 
     blob,
     covr,
-    dbplyr (>= 2.2.1),
-    dplyr (>= 0.7.0),
+    dbplyr (>= 2.4.0),
+    dplyr (>= 1.1.0),
     hms,
     readr,
     sodium,
diff --git a/NEWS.md b/NEWS.md
index 235a5005..7fe1c7e0 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,8 @@
 # bigrquery (development version)
 
+* Added a translation for `runif(n())`. This fixes the translation for
+  `slice_sample()` (@mgirlich, #448).
+
 * Add a `dbQuoteLiteral()` method for logicals to revert breaking change 
   introduced by DBI 1.1.2 (@meztez, #478).
 
diff --git a/R/dplyr.R b/R/dplyr.R
index 14333dee..371a224b 100644
--- a/R/dplyr.R
+++ b/R/dplyr.R
@@ -253,7 +253,11 @@ sql_translation.BigQueryConnection <- function(x) {
       pmin = sql_prefix("LEAST"),
 
       # Median
-      median = function(x) dbplyr::build_sql("APPROX_QUANTILES(", x, ", 2)[SAFE_ORDINAL(2)]")
+      median = function(x) dbplyr::build_sql("APPROX_QUANTILES(", x, ", 2)[SAFE_ORDINAL(2)]"),
+
+      runif = function(n = n(), min = 0, max = 1) {
+        dbplyr::sql_runif(RAND(), n = {{ n }}, min = min, max = max)
+      },
     ),
     dbplyr::sql_translator(.parent = dbplyr::base_agg,
       n = function() dplyr::sql("count(*)"),
diff --git a/tests/testthat/test-dplyr.R b/tests/testthat/test-dplyr.R
index 33793fd5..0bc812fa 100644
--- a/tests/testthat/test-dplyr.R
+++ b/tests/testthat/test-dplyr.R
@@ -130,6 +130,13 @@ test_that("suffixes use _", {
   expect_equal(dbplyr::sql_join_suffix(simulate_bigrquery()), c("_x", "_y"))
 })
 
+test_that("runif is correctly translated", {
+  expect_equal(
+    dbplyr::translate_sql(runif(n()), con = simulate_bigrquery()),
+    dbplyr::sql("RAND()")
+  )
+})
+
 test_that("can correctly print a lazy query", {
   con <- DBI::dbConnect(
     bigquery(),