From 1fea27aa65b9513aa7bf9fb5b32fde57e180fba8 Mon Sep 17 00:00:00 2001
From: Ahmed Mohamed <amfy10@gmail.com>
Date: Wed, 4 Nov 2020 15:23:26 +1000
Subject: [PATCH 1/2] Update `grepl` SQL translation to match REGEXP_CONTAINS
 signature

`grepl` function in base R is incorrectly translated to `REGEXP_CONTAINS` by direct replacement. However, both reverse arguments order:
 - `grepl(pattern, x)`
 - `REGEXP_CONTAINS(value, regexp)`

This PR fixes the order of arguments for `REGEXP_CONTAINS`.
---
 R/dplyr.R | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/R/dplyr.R b/R/dplyr.R
index dc82bc45..182c7c0a 100644
--- a/R/dplyr.R
+++ b/R/dplyr.R
@@ -189,7 +189,9 @@ sql_translate_env.BigQueryConnection <- function(x) {
       Sys.time = sql_prefix("current_time"),
 
       # Regular expressions
-      grepl = sql_prefix("REGEXP_CONTAINS", 2),
+      grepl = function(pattern, x) {
+        dbplyr::build_sql("REGEXP_CONTAINS", list(x, pattern))
+      },
       gsub = function(match, replace, x) {
         dbplyr::build_sql("REGEXP_REPLACE", list(x, match, replace))
       },

From 72a615f8cdb3ffd34b7d9bf381439224e2aa34a2 Mon Sep 17 00:00:00 2001
From: Hadley Wickham <h.wickham@gmail.com>
Date: Wed, 8 Nov 2023 08:53:01 -0600
Subject: [PATCH 2/2] Add test & news bullet

---
 NEWS.md                        |  3 +++
 R/dplyr.R                      |  6 ++++--
 tests/testthat/_snaps/dplyr.md | 11 +++++++++++
 tests/testthat/test-dplyr.R    |  9 +++++++++
 4 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 4f09ec29..f73bd3eb 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,8 @@
 # bigrquery (development version)
 
+* `grepl(pattern, x)` is now correctly translated to 
+  `REGEXP_CONTAINS(x, pattern)` (#416).
+
 * `median()` gets a translation that works in `summarise()` and a clear
   error if you use it in `mutate()` (#419).
 
diff --git a/R/dplyr.R b/R/dplyr.R
index b56592ec..304e648f 100644
--- a/R/dplyr.R
+++ b/R/dplyr.R
@@ -233,10 +233,12 @@ sql_translation.BigQueryConnection <- function(x) {
 
       # Regular expressions
       grepl = function(pattern, x) {
+        # https://cloud.google.com/bigquery/docs/reference/standard-sql/string_functions#regexp_contains
         dbplyr::build_sql("REGEXP_CONTAINS", list(x, pattern))
       },
-      gsub = function(match, replace, x) {
-        dbplyr::build_sql("REGEXP_REPLACE", list(x, match, replace))
+      gsub = function(pattern, replace, x) {
+        # https://cloud.google.com/bigquery/docs/reference/standard-sql/string_functions#regexp_replace
+        dbplyr::build_sql("REGEXP_REPLACE", list(x, pattern, replace))
       },
 
       # Other scalar functions
diff --git a/tests/testthat/_snaps/dplyr.md b/tests/testthat/_snaps/dplyr.md
index 936bcc1f..7e46b1ad 100644
--- a/tests/testthat/_snaps/dplyr.md
+++ b/tests/testthat/_snaps/dplyr.md
@@ -6,3 +6,14 @@
       Error in `db_copy_to()`:
       ! BigQuery does not support temporary tables
 
+# string functions correctly
+
+    Code
+      dbplyr::translate_sql(grepl("a.c", x), con = con)
+    Output
+      <SQL> REGEXP_CONTAINS(`x`, 'a.c')
+    Code
+      dbplyr::translate_sql(gsub("a.c", "", x), con = con)
+    Output
+      <SQL> REGEXP_REPLACE(`x`, 'a.c', '')
+
diff --git a/tests/testthat/test-dplyr.R b/tests/testthat/test-dplyr.R
index 7f6bbd38..8cd2e1be 100644
--- a/tests/testthat/test-dplyr.R
+++ b/tests/testthat/test-dplyr.R
@@ -137,6 +137,15 @@ test_that("runif is correctly translated", {
   )
 })
 
+test_that("string functions correctly", {
+  con <- simulate_bigrquery()
+
+  expect_snapshot({
+    dbplyr::translate_sql(grepl("a.c", x), con = con)
+    dbplyr::translate_sql(gsub("a.c", "", x), con = con)
+  })
+})
+
 test_that("median is correctly translated", {
   expect_equal(
     dbplyr::translate_sql(median(x), con = simulate_bigrquery(), window = FALSE),