Allow configuration of load_all() call (#1637)

And load helpers to the search path by default to match previous behaviour.

Closes #1636

NEWS.md

@@ -1,5 +1,17 @@
 # testthat (development version)
 
+* You can now configure the behaviour of the implicit
+  `devtools::load_all()` call performed by `devtools::test()` in your
+  package DESCRIPTION file (#1636). To disable exports of internal
+  functions and of testthat helpers, use:
+
+  ```
+  Config/testthat/load-all: list(export_all = FALSE, helpers = FALSE)
+  ```
+
+  Helpers are now attached on the search path by default after calling
+  `devtools::test()`.
+
 # testthat 3.1.4
 
 * Minor tweaks to output for latest cli (#1606).

R/test-files.R

@@ -53,6 +53,12 @@
 #'   * "none", the default, doesn't load the package.
 #'   * "installed", uses [library()] to load an installed package.
 #'   * "source", uses [pkgload::load_all()] to a source package.
+#'     To configure the arguments passed to `load_all()`, add this
+#'     field in your DESCRIPTION file:
+#'
+#'     ```
+#'     Config/testthat/load-all: list(export_all = FALSE, helpers = FALSE)
+#'     ```
 #' @param wrap DEPRECATED
 #' @keywords internal
 #' @return A list (invisibly) containing data about the test results.
@@ -217,15 +223,47 @@ test_files_setup_env <- function(test_package,
   library(testthat)
 
   load_package <- arg_match(load_package)
-  switch(load_package,
-    none = {},
-    installed = library(test_package, character.only = TRUE),
-    source = pkgload::load_all(test_dir, helpers = FALSE, quiet = TRUE)
-  )
+  if (load_package == "installed") {
+    library(test_package, character.only = TRUE)
+  } else if (load_package == "source") {
+    # Allow configuring what we export to the search path (#1636)
+    args <- find_load_all_args(test_dir)
+    pkgload::load_all(
+      test_dir,
+      export_all = args[["export_all"]],
+      helpers = args[["helpers"]],
+      quiet = TRUE
+    )
+  }
 
   env %||% test_env(test_package)
 }
 
+find_load_all_args <- function(path) {
+  default <- list(export_all = TRUE, helpers = TRUE)
+
+  desc <- find_description(path)
+  if (is.null(desc)) {
+    return(default)
+  }
+
+  args <- desc$get_field("Config/testthat/load-all", default = NULL)
+  if (is.null(args)) {
+    return(default)
+  }
+
+  args <- parse_expr(args)
+  if (!is_call(args, "list")) {
+    abort("`Config/testthat/load-all` must be a list.", call = NULL)
+  }
+
+  args <- as.list(args[-1])
+  list(
+    export_all = args[["export_all"]] %||% default[["export_all"]],
+    helpers = args[["helpers"]] %||% default[["helpers"]]
+  )
+}
+
 test_files_setup_state <- function(test_dir, test_package, load_helpers, env, .env = parent.frame()) {
 
   # Define testing environment

tests/testthat/test-test-files.R

@@ -81,3 +81,25 @@ test_that("can filter test scripts", {
   expect_equal(filter_test_scripts(x, ".R"), character())
 })
 
+# ----------------------------------------------------------------------
+
+test_that("can configure `load_all()` (#1636)", {
+  path <- test_path("testConfigLoadAll")
+
+  args <- find_load_all_args(path)
+  expect_equal(args, list(export_all = FALSE, helpers = FALSE))
+
+  results <- test_local(path, reporter = "silent")
+  for (res in results) {
+    expect_equal(sum(res[["failed"]]), 0)
+  }
+})
+
+test_that("helpers are attached to the search path after running `devtools::test()`", {
+  # This is FALSE under R CMD check
+  skip_if_not(pkgload::is_dev_package("testthat"))
+
+  expect_true(
+    "rlang_version" %in% names(pkg_env("testthat"))
+  )
+})

tests/testthat/testConfigLoadAll/DESCRIPTION

@@ -0,0 +1,18 @@
+Package: testConfigLoadAll
+Title: What the Package Does (One Line, Title Case)
+Version: 0.0.0.9000
+Authors@R: 
+    person("First", "Last", , "first.last@example.com", role = c("aut", "cre"),
+           comment = c(ORCID = "YOUR-ORCID-ID"))
+Description: What the package does (one paragraph).
+License: `use_mit_license()`, `use_gpl3_license()` or friends to pick a
+    license
+Encoding: UTF-8
+Roxygen: list(markdown = TRUE)
+RoxygenNote: 7.2.0
+Config/testthat/load-all: list(export_all = FALSE, helpers = FALSE)
+Imports:
+    rlang
+Suggests: 
+    testthat (>= 3.0.0)
+Config/testthat/edition: 3

tests/testthat/testConfigLoadAll/NAMESPACE

@@ -0,0 +1,3 @@
+# Generated by roxygen2: do not edit by hand
+
+export(exported)

tests/testthat/testConfigLoadAll/R/config.R

@@ -0,0 +1,4 @@
+internal <- function() NULL
+
+#' @export
+exported <- function() NULL

tests/testthat/testConfigLoadAll/tests/testthat.R

@@ -0,0 +1,12 @@
+# This file is part of the standard setup for testthat.
+# It is recommended that you do not modify it.
+#
+# Where should you do additional test configuration?
+# Learn more about the roles of various files in:
+# * https://r-pkgs.org/tests.html
+# * https://testthat.r-lib.org/reference/test_package.html#special-files
+
+library(testthat)
+library(testConfigLoadAll)
+
+test_check("testConfigLoadAll")

tests/testthat/testConfigLoadAll/tests/testthat/helper-config.R

@@ -0,0 +1 @@
+my_helper <- function() NULL

tests/testthat/testConfigLoadAll/tests/testthat/test-config.R

@@ -0,0 +1,11 @@
+test_that("helpers are not on the path", {
+  expect_false(
+    "my_helper" %in% names(rlang::pkg_env("testConfigLoadAll"))
+  )
+})
+
+test_that("internal functions are not on the path", {
+  fns <- names(rlang::pkg_env("testConfigLoadAll"))
+  expect_false("internal" %in% fns)
+  expect_true("exported" %in% fns)
+})