From b0e22960e7738c9b9de0e3ce1b38e14881b252f2 Mon Sep 17 00:00:00 2001
From: Hadley Wickham <h.wickham@gmail.com>
Date: Mon, 6 Jan 2025 07:19:37 -0600
Subject: [PATCH] Minor `curl_translate()` polishing/testing (#619)

Fixes #500
---
 R/curl.R                      |  4 +++-
 R/headers.R                   | 14 +++++---------
 tests/testthat/_snaps/curl.md | 11 +++++++++++
 tests/testthat/test-curl.R    | 14 +++++++++++++-
 4 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/R/curl.R b/R/curl.R
index 6016638d..acd4b946 100644
--- a/R/curl.R
+++ b/R/curl.R
@@ -56,7 +56,9 @@ curl_translate <- function(cmd, simplify_headers = TRUE) {
 
   # Content type set with data
   type <- data$headers$`Content-Type`
-  data$headers$`Content-Type` <- NULL
+  if (!identical(data$data, "")) {
+    data$headers$`Content-Type` <- NULL
+  }
 
   headers <- curl_simplify_headers(data$headers, simplify_headers)
   steps <- add_curl_step(steps, "req_headers", dots = headers)
diff --git a/R/headers.R b/R/headers.R
index 6fdc5dd2..c5c4057a 100644
--- a/R/headers.R
+++ b/R/headers.R
@@ -1,15 +1,11 @@
 as_headers <- function(x, error_call = caller_env()) {
   if (is.character(x) || is.raw(x)) {
-    headers <- curl::parse_headers(x)
-    headers <- headers[grepl(":", headers, fixed = TRUE)]
+    parsed <- curl::parse_headers(x)
+    valid <- parsed[grepl(":", parsed, fixed = TRUE)]
+    halves <- parse_in_half(valid, ":")
 
-    equals <- regexpr(":", headers, fixed = TRUE)
-    pieces <- regmatches(headers, equals, invert = TRUE)
-
-    names <- map_chr(pieces, "[[", 1)
-    values <- as.list(trimws(map_chr(pieces, "[[", 2)))
-
-    new_headers(set_names(values, names), error_call = error_call)
+    headers <- set_names(trimws(halves$right), halves$left)
+    new_headers(as.list(headers), error_call = error_call)
   } else if (is.list(x)) {
     new_headers(x, error_call = error_call)
   } else {
diff --git a/tests/testthat/_snaps/curl.md b/tests/testthat/_snaps/curl.md
index 5d42dfa3..1c5cface 100644
--- a/tests/testthat/_snaps/curl.md
+++ b/tests/testthat/_snaps/curl.md
@@ -104,6 +104,17 @@
         req_body_raw("abcdef", "text/plain") |> 
         req_perform()
 
+# content type stays in header if no data
+
+    Code
+      curl_translate("curl http://example.com -H Content-Type:text/plain")
+    Output
+      request("http://example.com/") |> 
+        req_headers(
+          `Content-Type` = "text/plain",
+        ) |> 
+        req_perform()
+
 # can read from clipboard
 
     Code
diff --git a/tests/testthat/test-curl.R b/tests/testthat/test-curl.R
index 225983a4..de170670 100644
--- a/tests/testthat/test-curl.R
+++ b/tests/testthat/test-curl.R
@@ -51,7 +51,11 @@ test_that("can handle line breaks", {
 test_that("headers are parsed", {
   expect_equal(
     curl_normalize("curl http://x.com -H 'A: 1'")$headers,
-    as_headers("A: 1")
+    new_headers(list(A = "1"))
+  )
+  expect_equal(
+    curl_normalize("curl http://x.com -H 'B:'")$headers,
+    new_headers(list(B = ""))
   )
 })
 
@@ -138,6 +142,14 @@ test_that("can translate data", {
   })
 })
 
+test_that("content type stays in header if no data", {
+  skip_if(getRversion() < "4.1")
+
+  expect_snapshot(
+    curl_translate("curl http://example.com -H Content-Type:text/plain")
+  )
+})
+
 test_that("can evaluate simple calls", {
   request_test() # hack to start server