Make parse NULL aware and add tests (#38)

* Test

* more tests

* Make parse `NULL` aware

* More tests

* Update doc

R/parse.R

@@ -1,11 +1,17 @@
 #' Use ada-url to parse a url
 #' @param url character. one or more URL to be parsed
 #' @param decode logical. Whether to decode the output (see [utils::URLdecode()]), default to `TRUE`
-#' @return A list of components of the url
+#' @return A data frame of components of the url
 #' @examples
 #' ada_url_parse("https://user_1:[email protected]:8080/dir/../api?q=1#frag")
 #' @export
 ada_url_parse <- function(url, decode = TRUE) {
+    if (is.null(url)) {
+        return(structure(list(href = character(0), protocol = character(0),
+                              username = character(0), password = character(0), host = character(0),
+                              hostname = character(0), port = character(0), pathname = character(0),
+                              search = character(0), hash = character(0)), row.names = integer(0), class = "data.frame"))
+    }
     url_parsed <- Rcpp_ada_parse(url)
     if (isTRUE(decode)) {
         return(.decoder(url_parsed))

tests/testthat/test-parse.R

@@ -21,6 +21,9 @@ test_that("works with utf8", {
   expect_equal(res[["pathname"]], "/zone/1/\u6e2f\u805e")
   res <- ada_url_parse("http://www.m\u00fcller.de")
   expect_equal(res[["host"]], "www.m\u00fcller.de")
+  res <- ada_url_parse("https://\u4e2d\u56fd\u79fb\u52a8.\u4e2d\u56fd")
+  expect_equal(res$href[1], "https://xn--fiq02ib9d179b.xn--fiqs8s/")
+  expect_equal(res$host[1], "\u4e2d\u56fd\u79fb\u52a8.\u4e2d\u56fd")
 })
 
 test_that("URLdecode optional #5", {
@@ -32,3 +35,13 @@ test_that("multiple urls", {
   urls <- rep("https://user_1:[email protected]:8080/dir/../api?q=1#frag", 5)
   expect_equal(nrow(ada_url_parse(urls)), 5L)
 })
+
+test_that("corner cases", {
+    expect_error(ada_url_parse())
+    expect_error(ada_url_parse(NULL), NA)
+    corners <- c(NA, NULL, "", "youcantparsethis", 1)
+    testthat::expect_error(x <- ada_url_parse(corners), NA)
+    testthat::expect_error(y <- ada_url_parse(corners, decode = FALSE), NA)
+    expect_equal(x$host, c(NA_character_, NA_character_, NA_character_, NA_character_))
+    expect_equal(y$host, c(NA_character_, NA_character_, NA_character_, NA_character_))
+})