Deal with empty bodies better. Closes #91

NEWS.md

@@ -1,5 +1,10 @@
 # httr 0.3.0.99
 
+* `has_content()` tells you if request has any content associated with it (#91)
+
+* `parse(type = "auto")` returns NULL if no content associated with request 
+  (#91).
+
 * `with_verbose()` makes it easier to see verbose information when http 
   requests are made within other functions (#87).
 

R/content-parse.r

@@ -12,6 +12,10 @@ parse_text <- function(content, type = NULL, encoding = NULL) {
 }
 
 parse_auto <- function(content, type = NULL, encoding = NULL, ...) {
+  if (length(content) == 0) {
+    return(NULL)
+  }
+
   if (is.null(type)) {
     stop("Unknown mime type: can't parse automatically. Use the type ",
       "argument to specify manually.", call. = FALSE)

R/content.r

@@ -81,3 +81,14 @@ parsed_content <- function(x, ...) {
   message("text_content() deprecated. Use parsed_content(x, as = 'parsed')")
   content(x, as = "parsed", ...)
 }
+
+#' Does the request have content associated with it?
+#'
+#' @keywords internal
+#' @export
+#' @examples
+#' has_content(POST("http://httpbin.org/post", body = FALSE))
+#' has_content(HEAD("http://httpbin.org/headers"))
+has_content <- function(x) {
+  length(r) == 0
+}

tests/testthat/test-content.R

@@ -0,0 +1,6 @@
+context("Content")
+
+test_that("parse content is null if no body", {
+  out <- content(HEAD("http://httpbin.org/headers"))
+  expect_equal(out, NULL)
+})