Respect Markdown Viewer preference for file URLs

app/src/uri/mod.rs

@@ -1223,8 +1223,8 @@ enum OpenFileAction {
 
 /// Pure routing decision for `open_file`. Extracted so it can be unit-tested without
 /// standing up a full `AppContext`.
-fn classify_open_file_action(path: &Path) -> OpenFileAction {
-    if is_markdown_file(path) {
+fn classify_open_file_action(path: &Path, prefer_markdown_viewer: bool) -> OpenFileAction {
+    if is_markdown_file(path) && prefer_markdown_viewer {
         OpenFileAction::Notebook
     } else if is_runnable_shell_script(path) {
         OpenFileAction::ExecuteInSession
@@ -1243,7 +1243,7 @@ fn can_open_file_editor_path(path: &Path) -> bool {
 }
 
 /// Handle an incoming `file://` URL.
-/// * Markdown files are opened as notebook panes.
+/// * Markdown files are opened as notebook panes when the viewer preference is enabled.
 /// * For directories, open a new session at the directory path.
 /// * For other files, open a new session at the parent directory path, then possibly execute the
 ///   file.
@@ -1253,7 +1253,15 @@ fn open_file(window_id: Option<WindowId>, path: PathBuf, ctx: &mut AppContext) {
             .map(|view_id| (window_id, view_id))
     });
 
-    let action = classify_open_file_action(&path);
+    #[cfg(feature = "local_fs")]
+    let prefer_markdown_viewer = {
+        use crate::util::file::external_editor::EditorSettings;
+        *EditorSettings::as_ref(ctx).prefer_markdown_viewer
+    };
+    #[cfg(not(feature = "local_fs"))]
+    let prefer_markdown_viewer = true;
+
+    let action = classify_open_file_action(&path, prefer_markdown_viewer);
 
     if action == OpenFileAction::Notebook {
         if let Some((primary_window_id, root_view_id)) = primary_window_and_view {

app/src/uri/uri_tests.rs

@@ -743,7 +743,7 @@ fn test_open_file_executable_sh_routes_to_execute() {
     let p = dir.path().join("run.sh");
     std::fs::write(&p, b"#!/bin/sh\n:\n").unwrap();
     std::fs::set_permissions(&p, std::fs::Permissions::from_mode(0o755)).unwrap();
-    let action = classify_open_file_action(&p);
+    let action = classify_open_file_action(&p, true);
     assert_eq!(action, OpenFileAction::ExecuteInSession);
 }
 
@@ -755,7 +755,7 @@ fn test_open_file_non_executable_sh_routes_to_editor() {
     let p = dir.path().join("view.sh");
     std::fs::write(&p, b"#!/bin/sh\n:\n").unwrap();
     std::fs::set_permissions(&p, std::fs::Permissions::from_mode(0o644)).unwrap();
-    assert_eq!(classify_open_file_action(&p), OpenFileAction::Editor);
+    assert_eq!(classify_open_file_action(&p, true), OpenFileAction::Editor);
 }
 
 #[test]
@@ -768,19 +768,30 @@ fn test_open_file_executable_bash_zsh_fish_route_to_execute() {
         std::fs::write(&p, b"#!/bin/sh\n:\n").unwrap();
         std::fs::set_permissions(&p, std::fs::Permissions::from_mode(0o755)).unwrap();
         assert_eq!(
-            classify_open_file_action(&p),
+            classify_open_file_action(&p, true),
             OpenFileAction::ExecuteInSession,
             "{name} should route to ExecuteInSession",
         );
     }
 }
 
 #[test]
-fn test_open_file_markdown_unchanged() {
+fn test_open_file_markdown_routes_to_notebook_when_viewer_enabled() {
     let dir = tempfile::tempdir().unwrap();
     let p = dir.path().join("README.md");
     std::fs::write(&p, b"# hi\n").unwrap();
-    assert_eq!(classify_open_file_action(&p), OpenFileAction::Notebook);
+    assert_eq!(
+        classify_open_file_action(&p, true),
+        OpenFileAction::Notebook
+    );
+}
+
+#[test]
+fn test_open_file_markdown_routes_to_editor_when_viewer_disabled() {
+    let dir = tempfile::tempdir().unwrap();
+    let p = dir.path().join("README.md");
+    std::fs::write(&p, b"# hi\n").unwrap();
+    assert_eq!(classify_open_file_action(&p, false), OpenFileAction::Editor);
 }
 
 #[test]
@@ -789,7 +800,7 @@ fn test_open_file_rust_source_still_opens_in_editor() {
     let dir = tempfile::tempdir().unwrap();
     let p = dir.path().join("main.rs");
     std::fs::write(&p, b"fn main() {}\n").unwrap();
-    assert_eq!(classify_open_file_action(&p), OpenFileAction::Editor);
+    assert_eq!(classify_open_file_action(&p, true), OpenFileAction::Editor);
 }
 
 #[test]
@@ -825,7 +836,7 @@ fn test_open_file_editor_binary_file_is_rejected() {
 fn test_open_file_directory_routes_to_session() {
     let dir = tempfile::tempdir().unwrap();
     assert_eq!(
-        classify_open_file_action(dir.path()),
+        classify_open_file_action(dir.path(), true),
         OpenFileAction::ExecuteInSession
     );
 }
@@ -841,7 +852,7 @@ fn test_open_file_non_runnable_shebang_routes_to_editor() {
     let p = dir.path().join("noext");
     std::fs::write(&p, b"#!/bin/sh\necho hi\n").unwrap();
     std::fs::set_permissions(&p, std::fs::Permissions::from_mode(0o644)).unwrap();
-    assert_eq!(classify_open_file_action(&p), OpenFileAction::Editor);
+    assert_eq!(classify_open_file_action(&p, true), OpenFileAction::Editor);
 }
 
 #[test]