Support both dbplyr < 2.6.0 and >= 2.6.0 with backwards compatibility

DESCRIPTION

@@ -53,7 +53,7 @@ Suggests:
     callr,
     clock,
     DBItest,
-    dbplyr,
+    dbplyr (>= 2.5.2),
     dplyr,
     rlang,
     testthat,

R/backend-dbplyr__duckdb_connection.R

@@ -69,8 +69,6 @@ duckdb_grepl <- function(pattern, x, ignore.case = FALSE, perl = FALSE, fixed =
 }
 
 duckdb_n_distinct <- function(..., na.rm = FALSE) {
-  sql <- pkg_method("sql", "dbplyr")
-  glue_sql2 <- pkg_method("glue_sql2", "dbplyr")
   sql_current_con <- pkg_method("sql_current_con", "dbplyr")
   check_dots_unnamed <- pkg_method("check_dots_unnamed", "rlang")
 
@@ -82,22 +80,23 @@ duckdb_n_distinct <- function(..., na.rm = FALSE) {
   check_dots_unnamed()
 
   # https://duckdb.org/docs/sql/data_types/struct.html#creating-structs-with-the-row-function
+  # Requires dbplyr >= 2.5.2 with exported sql_glue()
   if (!identical(na.rm, FALSE)) {
     if (length(list(...)) == 1L) {
       # in case of only one column fall back to the "simple" version
-      return(glue_sql2(con, "COUNT(DISTINCT {.col {list(...)}*})"))
+      return(dbplyr::sql_glue(con, "COUNT(DISTINCT {.col {list(...)}*})"))
     } else {
       str_null_check <-
-        sql(paste0(paste0(list(...), " IS NOT NULL"), collapse = " AND "))
+        dbplyr::sql(paste0(paste0(list(...), " IS NOT NULL"), collapse = " AND "))
 
-      return(glue_sql2(
+      return(dbplyr::sql_glue(
         con,
         "COUNT(DISTINCT row({.col {list(...)}*})) FILTER (",
         str_null_check, ")"
       ))
     }
   } else {
-    return(glue_sql2(con, "COUNT(DISTINCT row({.col {list(...)}*}))"))
+    return(dbplyr::sql_glue(con, "COUNT(DISTINCT row({.col {list(...)}*}))"))
   }
 }