Update grepl SQL translation to match REGEXP_CONTAINS signature

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).
 

R/dplyr.R

@@ -232,9 +232,13 @@ sql_translation.BigQueryConnection <- function(x) {
       Sys.time = sql_prefix("current_time"),
 
       # Regular expressions
-      grepl = sql_prefix("REGEXP_CONTAINS", 2),
-      gsub = function(match, replace, x) {
-        dbplyr::build_sql("REGEXP_REPLACE", list(x, match, replace))
+      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(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

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', '')
+

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),