Tweak dependency handling

* Bump required version of DBI. Fixes #178.
* Message if dbplyr is old. Fixes #179 (as much as possible)

DESCRIPTION

@@ -18,13 +18,13 @@ Depends:
     methods,
     R (>= 3.6.0)
 Imports:
-    DBI,
+    DBI (>= 1.2.1),
     later (>= 1.0.0),
     R6,
     rlang (>= 1.0.0)
 Suggests:
     covr,
-    dbplyr (>= 2.0.0),
+    dbplyr (>= 2.4.0),
     dplyr,
     knitr,
     rmarkdown,
@@ -39,4 +39,4 @@ Config/Needs/website: tidyverse/tidytemplate
 Config/testthat/edition: 3
 Encoding: UTF-8
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 7.3.0
+RoxygenNote: 7.3.1

NAMESPACE

@@ -64,3 +64,4 @@ import(rlang)
 importFrom(DBI,dbBreak)
 importFrom(R6,R6Class)
 importFrom(later,later)
+importFrom(utils,packageVersion)

NEWS.md

@@ -1,5 +1,8 @@
 # pool (development version)
 
+* Now requires DBI 1.2.0 (#178) and messages if you're using an old dbplyr 
+  (#179).
+
 # pool 1.0.2
 
 * No longer depends on the withr package, by instead requiring R 3.6.

R/dbplyr.R

@@ -79,6 +79,8 @@ dbplyr_register_methods <- function() {
 
   # Wrappers inspect formals so can only be executed if dbplyr is available
   on_package_load("dbplyr", {
+    check_dbplyr()
+
     dbplyr_s3_register <- function(fun_name) {
       s3_register(paste0("dbplyr::", fun_name), "Pool", dbplyr_wrap(fun_name))
     }
@@ -95,6 +97,19 @@ dbplyr_register_methods <- function() {
   })
 }
 
+check_dbplyr <- function() {
+  if (packageVersion("dbplyr") < "2.4.0") {
+    inform(
+      c(
+        "!" = "Pool works best with dbplyr 2.4.0 or greater.",
+        i = paste0("You have dbplyr ", packageVersion("dbplyr"), "."),
+        i = "Please consider upgrading."
+      ),
+      class = c("packageStartupMessage", "simpleMessage")
+    )
+  }
+}
+
 dbplyr_wrap <- function(fun_name) {
   fun <- utils::getFromNamespace(fun_name, "dbplyr")
   args <- formals(fun)

R/pool-package.R

@@ -8,3 +8,8 @@
 #' @importFrom later later
 #' @import rlang
 NULL
+
+## usethis namespace: start
+#' @importFrom utils packageVersion
+## usethis namespace: end
+NULL

tests/testthat/_snaps/dbplyr.md

@@ -57,3 +57,12 @@
       }
       <environment: namespace:pool>
 
+# warns if dbplyr is old
+
+    Code
+      check_dbplyr()
+    Message
+      ! Pool works best with dbplyr 2.4.0 or greater.
+      i You have dbplyr 1.0.0.
+      i Please consider upgrading.
+

tests/testthat/test-dbplyr.R

@@ -91,3 +91,15 @@ test_that("wrapper looks good", {
     dbplyr_wrap("db_compute")
   })
 })
+
+test_that("warns if dbplyr is old", {
+  local_mocked_bindings(packageVersion = function(...) "1.0.0")
+  expect_snapshot({
+    check_dbplyr()
+  })
+
+  cnd_dplyr <- class(catch_cnd(check_dbplyr()))
+  cnd_startup <- class(catch_cnd(packageStartupMessage("hi")))
+  cnd_startup <- c(cnd_startup[1:2], "rlang_message", cnd_startup[-(1:2)])
+  expect_equal(cnd_dplyr, cnd_startup)
+})