Fix 838

R/add_r_files.R

@@ -9,6 +9,8 @@ add_r_files <- function(
 	open = TRUE,
 	dir_create = TRUE,
 	with_test = FALSE,
+	template = NULL,
+	...,
 	pkg
 ) {
 	signal_arg_is_deprecated(
@@ -140,12 +142,26 @@ add_r_files <- function(
 					module
 				)
 		) {
-			# Must be a function or utility file being created
-			append_roxygen_comment(
-				name = name,
-				path = where,
-				ext = ext
-			)
+			if (
+				ext == "fct" &&
+					!is.null(
+						template
+					)
+			) {
+				template(
+					name = name,
+					path = where,
+					export = FALSE,
+					...
+				)
+			} else {
+				# Must be a function or utility file being created
+				append_roxygen_comment(
+					name = name,
+					path = where,
+					ext = ext
+				)
+			}
 		}
 
 		cat_created(
@@ -184,6 +200,10 @@ add_r_files <- function(
 #' @param name The name of the file
 #' @param module If not NULL, the file will be module specific
 #'     in the naming (you don't need to add the leading `mod_`).
+#' @param template Function writing the default contents of a function file.
+#'     Defaults to the built-in function template. Ignored for
+#'     module-specific files.
+#' @param ... Arguments passed to the `template` function.
 #' @inheritParams  add_module
 #'
 #' @rdname file_creation
@@ -197,6 +217,8 @@ add_fct <- function(
 	open = TRUE,
 	dir_create = TRUE,
 	with_test = FALSE,
+	template = fct_template,
+	...,
 	pkg
 ) {
 	signal_arg_is_deprecated(
@@ -207,13 +229,15 @@ add_fct <- function(
 		"pkg"
 	)
 	add_r_files(
-		name,
-		module,
+		name = name,
 		ext = "fct",
+		module = module,
 		golem_wd = golem_wd,
 		open = open,
 		dir_create = dir_create,
-		with_test = with_test
+		with_test = with_test,
+		template = template,
+		...
 	)
 }
 
@@ -236,9 +260,9 @@ add_utils <- function(
 		"pkg"
 	)
 	add_r_files(
-		name,
-		module,
+		name = name,
 		ext = "utils",
+		module = module,
 		golem_wd = golem_wd,
 		open = open,
 		dir_create = dir_create,
@@ -265,15 +289,42 @@ add_r6 <- function(
 		"pkg"
 	)
 	add_r_files(
-		name,
-		module,
+		name = name,
 		ext = "class",
+		module = module,
 		golem_wd = golem_wd,
 		open = open,
 		dir_create = dir_create,
 		with_test = with_test
 	)
 }
+
+#' Default template for `add_fct()`
+#'
+#' This function does not aim at being called as is by
+#' users, but to be passed as an argument to [add_fct()].
+#'
+#' @param path The path to the R script where the function will be written.
+#' @param name The name of the generated function.
+#' @param export Whether the generated function should be exported.
+#'
+#' @return Used for side effect
+#' @keywords internal
+#' @noRd
+fct_template <- function(
+	name,
+	path,
+	export = FALSE,
+	...
+) {
+	append_roxygen_comment(
+		name = name,
+		path = path,
+		ext = "fct",
+		export = export
+	)
+}
+
 #' Append roxygen comments to `fct_` and `utils_` files
 #'
 #' This function add boilerplate roxygen comments

tests/testthat/test-add_r_files.R

@@ -236,3 +236,86 @@ test_that("add_fct sanitizes names correctly", {
 		)
 	})
 })
+
+test_that("fct_template works", {
+	fct_template(
+		"my_fun",
+		path <- tempfile(),
+		export = TRUE
+	)
+	on.exit({
+		unlink(
+			path,
+			recursive = TRUE,
+			force = TRUE
+		)
+	})
+	fct_read <- paste(
+		readLines(
+			path
+		),
+		collapse = " "
+	)
+	expect_true(
+		grepl(
+			"my_fun <- function",
+			fct_read
+		)
+	)
+	expect_true(
+		grepl(
+			"@export",
+			fct_read
+		)
+	)
+})
+
+test_that("add_fct accepts a template", {
+	run_quietly_in_a_dummy_golem({
+		add_fct(
+			"custom",
+			open = FALSE,
+			template = function(
+				name,
+				path,
+				export = FALSE,
+				...
+			) {
+				writeLines(
+					c(
+						"#' custom function",
+						if (export) "#' @export" else "#' @noRd",
+						sprintf(
+							"%s <- function() \"ok\"",
+							name
+						)
+					),
+					con = path
+				)
+			}
+		)
+
+		expect_exists(
+			file.path(
+				"R",
+				"fct_custom.R"
+			)
+		)
+
+		file_content <- paste(
+			readLines(
+				file.path(
+					"R",
+					"fct_custom.R"
+				)
+			),
+			collapse = " "
+		)
+		expect_true(
+			grepl(
+				'custom <- function\\(\\) "ok"',
+				file_content
+			)
+		)
+	})
+})