output_file now map to output-file Quarto meta and not the cli flag

````
quarto_render("test.qmd", quarto_args = c("--output", "test.html"))
````
Can restore the previous behavior by setting the command line flag

Author: cderv

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: quarto
 Title: R Interface to 'Quarto' Markdown Publishing System
-Version: 1.4.4.9017
+Version: 1.4.4.9018
 Authors@R: c(
     person("JJ", "Allaire", , "[email protected]", role = "aut",
            comment = c(ORCID = "0000-0003-0174-9868")),

NEWS.md

@@ -1,5 +1,7 @@
 # quarto (development version)
 
+- `quarto_render(output_file = )` now sets the `output-file` Quarto metadata instead of the `--output` CLI flag. This allows the output file information to correctly be processed by Quarto, as if passed in a YAML header. e.g. it allows to support multiple output formats in the same render call. `quarto_render(quarto_args = c('--output', 'dummy.html'))` can still be used to set the `--output` CLI flag to enforce using the CLI flag and not the metadata processed by Quarto (#251, #43).
+
 - Added `check_newer_version()` function to check if a newer version of Quarto is available. The function compares the current Quarto version against the latest stable and prerelease versions. It is aimed for verbosity by default (`verbose = TRUE`), but `verbose = FALSE` can also be set for just checking update availability with TRUE or FALSE return values. Version information is cached per session for up to 24 hours to minimize network requests.
 
 - Added `write_yaml_metadata_block()` function to dynamically set YAML metadata in Quarto documents from R code chunks. This addresses the limitation where Quarto metadata must be static and defined in the document header. The function enables conditional content and metadata-driven document behavior based on R computations (thanks, @kmasiello, #137, #160).

R/render.R

@@ -154,8 +154,11 @@ quarto_render <- function(
   if (!missing(output_format)) {
     args <- c(args, "--to", paste(output_format, collapse = ","))
   }
-  if (!missing(output_file)) {
-    args <- c(args, "--output", output_file)
+  if (!is.null(output_file)) {
+    # handle problem with cli flag
+    # https://github.com/quarto-dev/quarto-cli/issues/8399
+    # args <- c(args, "--output", output_file)
+    metadata[['output-file']] <- output_file
   }
   if (!missing(execute)) {
     args <- c(args, ifelse(isTRUE(execute), "--execute", "--no-execute"))
@@ -187,7 +190,7 @@ quarto_render <- function(
     args <- c(args, "--cache-refresh")
   }
   # metadata to pass to quarto render
-  if (!missing(metadata)) {
+  if (!is.null(metadata)) {
     # We merge meta if there is metadata_file passed
     if (!missing(metadata_file)) {
       metadata <- merge_list(

tests/testthat/test-render.R

@@ -99,3 +99,26 @@ test_that("`quarto_render(as_job = TRUE)` is wrapable", {
   Sys.sleep(10)
   expect_true(file.exists(output))
 })
+
+test_that("quarto_render allows to pass output-file meta", {
+  skip_if_no_quarto()
+  qmd <- local_qmd_file(c(
+    "---",
+    "title: Example title",
+    "format:",
+    "    html:",
+    "       toc: true",
+    "    docx:",
+    "        toc: true",
+    "---",
+    ""
+  ))
+  out <- quarto_render(
+    qmd,
+    output_file = "final_report",
+    output_format = "all",
+    quiet = TRUE
+  )
+  expect_true(file.exists("final_report.html"))
+  expect_true(file.exists("final_report.docx"))
+})