Don't normalize HTTP URLs for the Viewer (#818)

* don't normalize URLs

* Localize special logic in `is_http_url()` helper (#821)

---------

Co-authored-by: Davis Vaughan <[email protected]>

Author: jmcphers

crates/ark/src/modules/positron/utils.R

@@ -1,7 +1,7 @@
 #
 # utils.R
 #
-# Copyright (C) 2022-2024 Posit Software, PBC. All rights reserved.
+# Copyright (C) 2022-2025 Posit Software, PBC. All rights reserved.
 #
 #
 
@@ -141,3 +141,7 @@ node_poke_cdr <- function(node, cdr) {
 is_string <- function(x) {
     is.character(x) && length(x) == 1 && !is.na(x)
 }
+
+is_http_url <- function(x) {
+    is_string(x) && grepl("^https?://", x)
+}

crates/ark/src/modules/positron/viewer.R

@@ -1,23 +1,31 @@
 #
 # viewer.R
 #
-# Copyright (C) 2023-2024 Posit Software, PBC. All rights reserved.
+# Copyright (C) 2023-2025 Posit Software, PBC. All rights reserved.
 #
 #
 
 options("viewer" = function(url, height = NULL, ...) {
     # Validate the URL argument.
-    if (!is.character(url) || (length(url) != 1))
-        stop("url must be a single element character vector.")
-
-    # Normalize paths for comparison. This is necessary because on e.g. macOS,
-    # the `tempdir()` may contain `//` or other non-standard path separators.
-    normalizedPath <- normalizePath(url, mustWork = FALSE)
-    normalizedTempdir <- normalizePath(tempdir(), mustWork = FALSE)
+    if (!is_string(url)) {
+        stop("`url` must be a string.")
+    }
 
     # Validate the height argument.
     height <- .ps.validate.viewer.height(height)
 
+    # Open `http(s)://` urls in the browser immediately, avoid normalizing their
+    # paths since they aren't files (posit-dev/positron#4843)
+    if (is_http_url(url)) {
+        return(utils::browseURL(url, ...))
+    }
+
+    # Normalize file paths for comparison against the `tempdir()`. This is
+    # necessary because on e.g. macOS, the `tempdir()` may contain `//` or other
+    # non-standard path separators.
+    normalizedPath <- normalizePath(url, mustWork = FALSE)
+    normalizedTempdir <- normalizePath(tempdir(), mustWork = FALSE)
+
     # Is the URL a temporary file?
     if (startsWith(normalizedPath, normalizedTempdir)) {
         # Derive a title for the viewer from the path.
@@ -26,7 +34,7 @@ options("viewer" = function(url, height = NULL, ...) {
         # If so, open it in the HTML viewer.
         .ps.Call("ps_html_viewer", normalizedPath, title, height, FALSE)
     } else {
-        # If not, open it in the system browser.
+        # If not, fall back to opening it in the system browser.
         utils::browseURL(normalizedPath, ...)
     }
 })

crates/ark/src/modules/rstudio/stubs.R

@@ -57,7 +57,10 @@
         stop("url must be a single element character vector.")
     height <- .ps.validate.viewer.height(height)
 
-    url <- normalizePath(url, mustWork = FALSE)
+    if (!is_http_url(url)) {
+        # Only normalize file path urls (posit-dev/positron#4843)
+        url <- normalizePath(url, mustWork = FALSE)
+    }
 
     # Derive a title for the viewer from the path.
     title <- .ps.viewer.title(url)