req_url_path_*() can handle empty ...

NEWS.md

@@ -1,5 +1,8 @@
 # httr2 (development version)
 
+* `req_url_path()` and `req_url_path_append()` can now handle `NULL` or empty
+  `...` and the elements of `...` can also have length > 1 (@mgirlich, #177).
+
 * `req_perform()` now has an `error_call` argument and communicates more clearly
   where the error occurred (@mgirlich, #187).
 

R/req-url.R

@@ -53,11 +53,7 @@ req_url_query <- function(.req, ...) {
 #' @rdname req_url
 req_url_path <- function(req, ...) {
   check_request(req)
-  path <- paste(..., sep = "/")
-
-  if (!grepl("^/", path)) {
-    path <- paste0("/", path)
-  }
+  path <- dots_to_path(...)
 
   req_url(req, url_modify(req$url, path = path))
 }
@@ -66,15 +62,20 @@ req_url_path <- function(req, ...) {
 #' @rdname req_url
 req_url_path_append <- function(req, ...) {
   check_request(req)
-  path <- paste(..., sep = "/")
+  path <- dots_to_path(...)
 
   url <- url_parse(req$url)
+  url$path <- paste0(sub("/$", "", url$path), path)
 
+  req_url(req, url_build(url))
+}
+
+dots_to_path <- function(...) {
+  path <- paste(c(...), collapse = "/")
   # Ensure we don't add duplicate /s
-  if (!grepl("^/", path)) {
+  if (path != "" && !grepl("^/", path)) {
     path <- paste0("/", path)
   }
-  url$path <- paste0(sub("/$", "", url$path), path)
 
-  req_url(req, url_build(url))
+  path
 }

tests/testthat/test-req-url.R

@@ -24,6 +24,24 @@ test_that("can append multiple components", {
   expect_equal(req_url_path_append(req, "a", "b")$url, "http://example.com/x/a/b")
 })
 
+test_that("can handle empty path", {
+  req <- request("http://example.com/x")
+  expect_equal(req_url_path(req)$url, "http://example.com")
+  expect_equal(req_url_path_append(req)$url, "http://example.com/x")
+  expect_equal(req_url_path(req, NULL)$url, "http://example.com")
+  expect_equal(req_url_path_append(req, NULL)$url, "http://example.com/x")
+
+  expect_equal(req_url_path(req, "")$url, "http://example.com")
+  expect_equal(req_url_path_append(req, "")$url, "http://example.com/x")
+})
+
+test_that("can handle path vector", {
+  req <- request("http://example.com/x")
+  expect_equal(req_url_path(req, c("a", "b"))$url, "http://example.com/a/b")
+  expect_equal(req_url_path_append(req, c("a", "b"))$url, "http://example.com/x/a/b")
+  expect_equal(req_url_path_append(req, c("a", "b"), NULL)$url, "http://example.com/x/a/b")
+})
+
 test_that("can set query params", {
   req <- request("http://example.com/")
   expect_equal(req_url_query(req, a = 1, b = 2)$url, "http://example.com/?a=1&b=2")