Rely on interpolation to print header values (#616)

So that we don't need to worry about escaping. Fixes #586

NEWS.md

@@ -1,5 +1,6 @@
 # httr2 (development version)
 
+* `print.request()` now correctly escapes `{}` in headers (#586).
 * New `req_headers_redacted()` provides a user-friendlier way to set redacted headers (#561).
 * `resp_link_url()` now works if there are multiple `Link` headers (#587).
 * New `url_modify()` makes it easier to modify an existing url (#464).

R/utils.R

@@ -8,7 +8,7 @@ bullets_with_header <- function(header, x) {
   as_simple <- function(x) {
     if (is.atomic(x) && length(x) == 1) {
       if (is.character(x)) {
-        paste0("'", x, "'")
+        paste0('"', x, '"')
       } else {
         format(x)
       }
@@ -18,7 +18,9 @@ bullets_with_header <- function(header, x) {
   }
   vals <- map_chr(x, as_simple)
 
-  cli::cli_li(paste0("{.field ", names(x), "}: ", vals))
+  for (i in seq_along(x)) {
+    cli::cli_li("{.field {names(x)[[i]]}}: {vals[[i]]}")
+  }
 }
 
 modify_list <- function(.x, ..., error_call = caller_env()) {

tests/testthat/_snaps/req.md

@@ -20,6 +20,18 @@
       POST https://example.com
       Body: multipart encoded data
 
+# printing headers works with {}
+
+    Code
+      req_headers(request("http://test"), x = "{z}", `{z}` = "x")
+    Message
+      <httr2_request>
+      GET http://test
+      Headers:
+      * x: "{z}"
+      * {z}: "x"
+      Body: empty
+
 # individually prints repeated headers
 
     Code
@@ -28,9 +40,9 @@
       <httr2_request>
       GET https://example.com
       Headers:
-      * A: '1'
-      * A: '2'
-      * A: '3'
+      * A: "1"
+      * A: "2"
+      * A: "3"
       Body: empty
 
 # check_request() gives useful error

tests/testthat/test-req.R

@@ -7,6 +7,10 @@ test_that("req has basic print method", {
   })
 })
 
+test_that("printing headers works with {}", {
+  expect_snapshot(req_headers(request("http://test"), x  = "{z}", `{z}` = "x"))
+})
+
 test_that("individually prints repeated headers", {
   expect_snapshot(request("https://example.com") %>% req_headers(A = 1:3))
 })
@@ -18,7 +22,7 @@ test_that("print method obfuscates Authorization header unless requested", {
   expect_false(any(grepl("SECRET", output, fixed = TRUE)))
 
   output <- testthat::capture_messages(print(req, redact_headers = FALSE))
-  expect_true(any(grepl("Authorization: 'Basic", output, fixed = TRUE)))
+  expect_true(any(grepl("Authorization: \"Basic", output, fixed = TRUE)))
   expect_false(any(grepl("REDACTED", output, fixed = TRUE)))
 })