feat(BREAKING/fmt): prompt or require deno fmt . when providing no files and no config files discovered

cli/tools/fmt.rs

@@ -48,6 +48,7 @@ use crate::cache::IncrementalCache;
 use crate::colors;
 use crate::factory::CliFactory;
 use crate::sys::CliSys;
+use crate::util;
 use crate::util::file_watcher;
 use crate::util::fs::canonicalize_path;
 use crate::util::path::get_extension;
@@ -165,6 +166,8 @@ fn resolve_paths_with_options_batches(
   cli_options: &CliOptions,
   fmt_flags: &FmtFlags,
 ) -> Result<Vec<PathsWithOptions>, AnyError> {
+  maybe_show_format_confirmation(cli_options, fmt_flags)?;
+
   let members_fmt_options =
     cli_options.resolve_fmt_options_for_members(fmt_flags)?;
   let mut paths_with_options_batches =
@@ -186,6 +189,37 @@ fn resolve_paths_with_options_batches(
   Ok(paths_with_options_batches)
 }
 
+fn maybe_show_format_confirmation(
+  cli_options: &CliOptions,
+  fmt_flags: &FmtFlags,
+) -> Result<(), AnyError> {
+  if fmt_flags.check
+    || !fmt_flags.files.include.is_empty()
+    || cli_options.workspace().deno_jsons().next().is_some()
+    || cli_options.workspace().package_jsons().next().is_some()
+  {
+    return Ok(());
+  }
+
+  let confirm_result =
+    util::console::confirm(util::console::ConfirmOptions {
+      default: true,
+      message: format!(
+        "{} It looks like you're not in a workspace. Are you sure you want to format the entire '{}' directory?",
+        colors::yellow("Warning"),
+        cli_options.initial_cwd().display()
+      ),
+    })
+    .unwrap_or(false);
+  if confirm_result {
+    Ok(())
+  } else {
+    bail!(
+      "Did not format non-workspace directory. Run again specifying the current directory (ex. `deno fmt .`)"
+    )
+  }
+}
+
 async fn format_files(
   caches: &Arc<Caches>,
   cli_options: &Arc<CliOptions>,

cli/tools/pm/outdated/interactive.rs

@@ -22,6 +22,8 @@ use unicode_width::UnicodeWidthStr;
 
 use crate::tools::pm::deps::DepId;
 use crate::tools::pm::deps::DepKind;
+use crate::util::console::HideCursorGuard;
+use crate::util::console::RawMode;
 
 #[derive(Debug)]
 pub struct PackageInfo {
@@ -249,31 +251,6 @@ fn highlight_new_version(current: &Version, new: &Version) -> String {
   }
 }
 
-struct RawMode {
-  needs_disable: bool,
-}
-
-impl RawMode {
-  fn enable() -> io::Result<Self> {
-    terminal::enable_raw_mode()?;
-    Ok(Self {
-      needs_disable: true,
-    })
-  }
-  fn disable(mut self) -> io::Result<()> {
-    self.needs_disable = false;
-    terminal::disable_raw_mode()
-  }
-}
-
-impl Drop for RawMode {
-  fn drop(&mut self) {
-    if self.needs_disable {
-      let _ = terminal::disable_raw_mode();
-    }
-  }
-}
-
 pub fn select_interactive(
   packages: Vec<PackageInfo>,
 ) -> anyhow::Result<Option<HashSet<DepId>>> {
@@ -305,7 +282,7 @@ pub fn select_interactive(
   }
 
   let mut state = State::new(packages)?;
-  stderr.execute(cursor::Hide)?;
+  let hide_cursor_guard = HideCursorGuard::hide()?;
 
   let instructions_width = format!("? {}", State::instructions_line()).width();
 
@@ -407,8 +384,7 @@ pub fn select_interactive(
 
   static_text.eprint_clear();
 
-  crossterm::execute!(&mut stderr, cursor::Show)?;
-
+  hide_cursor_guard.show()?;
   raw_mode.disable()?;
 
   if do_it {

cli/util/console.rs

@@ -1,9 +1,160 @@
 // Copyright 2018-2025 the Deno authors. MIT license.
 
+use std::io;
+use std::sync::Arc;
+
+use crossterm::ExecutableCommand;
+use crossterm::cursor;
+use crossterm::event::KeyCode;
+use crossterm::event::KeyEvent;
+use crossterm::event::KeyEventKind;
+use crossterm::event::KeyModifiers;
+use crossterm::terminal;
+use deno_core::parking_lot::Mutex;
 use deno_runtime::ops::tty::ConsoleSize;
 
+use super::draw_thread::DrawThread;
+
 /// Gets the console size.
 pub fn console_size() -> Option<ConsoleSize> {
   let stderr = &deno_runtime::deno_io::STDERR_HANDLE;
   deno_runtime::ops::tty::console_size(stderr).ok()
 }
+
+pub struct RawMode {
+  needs_disable: bool,
+}
+
+impl RawMode {
+  pub fn enable() -> io::Result<Self> {
+    terminal::enable_raw_mode()?;
+    Ok(Self {
+      needs_disable: true,
+    })
+  }
+
+  pub fn disable(mut self) -> io::Result<()> {
+    self.needs_disable = false;
+    terminal::disable_raw_mode()
+  }
+}
+
+impl Drop for RawMode {
+  fn drop(&mut self) {
+    if self.needs_disable {
+      let _ = terminal::disable_raw_mode();
+    }
+  }
+}
+
+pub struct HideCursorGuard {
+  needs_disable: bool,
+}
+
+impl HideCursorGuard {
+  pub fn hide() -> io::Result<Self> {
+    io::stderr().execute(cursor::Hide)?;
+    Ok(Self {
+      needs_disable: true,
+    })
+  }
+
+  pub fn show(mut self) -> io::Result<()> {
+    self.needs_disable = false;
+    io::stderr().execute(cursor::Show)?;
+    Ok(())
+  }
+}
+
+impl Drop for HideCursorGuard {
+  fn drop(&mut self) {
+    if self.needs_disable {
+      _ = io::stderr().execute(cursor::Show);
+    }
+  }
+}
+
+#[derive(Debug)]
+pub struct ConfirmOptions {
+  pub message: String,
+  pub default: bool,
+}
+
+/// Prompts and confirms if a tty.
+///
+/// Returns `None` when a tty.
+pub fn confirm(options: ConfirmOptions) -> Option<bool> {
+  #[derive(Debug)]
+  struct PromptRenderer {
+    options: ConfirmOptions,
+    selection: Arc<Mutex<String>>,
+  }
+
+  impl super::draw_thread::DrawThreadRenderer for PromptRenderer {
+    fn render(&self, _data: &ConsoleSize) -> String {
+      let is_yes_default = self.options.default;
+      let selection = self.selection.lock();
+      format!(
+        "{} [{}/{}] {}",
+        self.options.message,
+        if is_yes_default { "Y" } else { "y" },
+        if is_yes_default { "n" } else { "N" },
+        *selection,
+      )
+    }
+  }
+
+  if !DrawThread::is_supported() {
+    return None;
+  }
+
+  let _raw_mode = RawMode::enable().ok()?;
+  let _hide_cursor_guard = HideCursorGuard::hide().ok()?;
+  let selection = Arc::new(Mutex::new(String::new()));
+  let default = options.default;
+  // uses a renderer and the draw thread in order to allow
+  // displaying other stuff on the draw thread while the prompt
+  // is showing
+  let renderer = PromptRenderer {
+    options,
+    selection: selection.clone(),
+  };
+  let _state = DrawThread::add_entry(Arc::new(renderer));
+
+  let mut selected = default;
+  loop {
+    let event = crossterm::event::read().ok()?;
+    #[allow(clippy::single_match)]
+    match event {
+      crossterm::event::Event::Key(KeyEvent {
+        kind: KeyEventKind::Press,
+        code,
+        modifiers,
+        ..
+      }) => match (code, modifiers) {
+        (KeyCode::Char('c'), KeyModifiers::CONTROL)
+        | (KeyCode::Char('q'), KeyModifiers::NONE) => break,
+        (KeyCode::Char('y'), KeyModifiers::NONE | KeyModifiers::SHIFT) => {
+          selected = true;
+          *selection.lock() = "Y".to_string();
+        }
+        (KeyCode::Char('n'), KeyModifiers::NONE | KeyModifiers::SHIFT) => {
+          selected = false;
+          *selection.lock() = "N".to_string();
+        }
+        (KeyCode::Backspace, _) => {
+          selected = default;
+          *selection.lock() = "".to_string();
+        }
+        // l is common for enter in vim keybindings
+        (KeyCode::Enter, _) | (KeyCode::Char('l'), KeyModifiers::NONE) => {
+          return Some(selected);
+        }
+        _ => {}
+      },
+      _ => {}
+    }
+  }
+
+  None
+}

tests/integration/fmt_tests.rs

@@ -214,7 +214,7 @@ fn fmt_auto_ignore_git_and_node_modules() {
     .new_command()
     .current_dir(t)
     .env("NO_COLOR", "1")
-    .args("fmt")
+    .args("fmt .")
     .run();
 
   output.assert_exit_code(1);
@@ -421,3 +421,21 @@ fn opt_out_top_level_exclude_via_fmt_unexclude() {
   assert_contains!(output, "excluded.ts");
   assert_not_contains!(output, "actually_excluded.ts");
 }
+
+#[test]
+fn test_tty_non_workspace_directory() {
+  let context = TestContextBuilder::new().use_temp_cwd().build();
+  let temp_dir = context.temp_dir().path();
+  temp_dir.join("main.ts").write("const a = 1;\n");
+  context.new_command().arg("fmt").with_pty(|mut pty| {
+    pty.expect("Are you sure you want to format the entire");
+    pty.write_raw("y\r\n");
+    pty.expect("Checked 1 file");
+  });
+
+  context.new_command().arg("fmt").with_pty(|mut pty| {
+    pty.expect("Are you sure you want to format");
+    pty.write_raw("n\r\n");
+    pty.expect("Did not format non-workspace directory");
+  });
+}

tests/integration/watcher_tests.rs

@@ -412,6 +412,7 @@ async fn fmt_watch_without_args_test() {
     .current_dir(t.path())
     .arg("fmt")
     .arg("--watch")
+    .arg(".")
     .piped_output()
     .spawn()
     .unwrap();

tests/specs/fmt/astro_file_with_css_comment/__test__.jsonc

@@ -1,5 +1,5 @@
 {
   "tempDir": true,
-  "args": "fmt --unstable-component",
+  "args": "fmt --unstable-component .",
   "output": "fmt.out"
 }

tests/specs/fmt/njk/__test__.jsonc

@@ -2,7 +2,7 @@
   "tempDir": true,
   "steps": [
     {
-      "args": "fmt --unstable-component",
+      "args": "fmt --unstable-component .",
       "output": "[WILDLINE]badly_formatted.njk\nChecked 1 file\n"
     },
     {

tests/specs/fmt/non_workspace/__test__.jsonc

@@ -0,0 +1,21 @@
+{
+  "tests": {
+    "bare": {
+      "args": "fmt",
+      "output": "error.out",
+      "exitCode": 1
+    },
+    "specify_dir": {
+      "args": "fmt .",
+      "output": "[WILDCARD]"
+    },
+    "check": {
+      "args": "fmt --check",
+      "output": "[WILDCARD]"
+    },
+    "arg": {
+      "args": "fmt main.ts",
+      "output": "[WILDCARD]"
+    }
+  }
+}

tests/specs/fmt/non_workspace/error.out

@@ -0,0 +1 @@
+error: Did not format non-workspace directory. Run again specifying the current directory (ex. `deno fmt .`)

tests/specs/fmt/sql/__test__.jsonc

@@ -2,11 +2,11 @@
   "tempDir": true,
   "tests": {
     "nothing": {
-      "args": "fmt",
+      "args": "fmt .",
       "output": "Checked 7 files\n"
     },
     "flag": {
-      "args": "fmt --unstable-sql",
+      "args": "fmt --unstable-sql .",
       "output": "[UNORDERED_START]\n[WILDLINE]badly_formatted.sql\n[WILDLINE]wrong_file_ignore.sql\n[UNORDERED_END]\nChecked 7 files\n"
     },
     "config_file": {

tests/specs/fmt/strip_bom/__test__.jsonc

@@ -5,7 +5,7 @@
     "output": "check.out",
     "exitCode": 1
   }, {
-    "args": "fmt",
+    "args": "fmt .",
     "output": "format.out"
   }, {
     "args": "run -R --unstable-raw-imports verify.ts",