12 files changed, 2376 insertions, 0 deletions

diff --git a/cli/util/checksum.rs b/cli/util/checksum.rs
new file mode 100644
index 000000000..c0e41356d
--- /dev/null
+++ b/cli/util/checksum.rs
@@ -0,0 +1,32 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use ring::digest::Context;
+use ring::digest::SHA256;
+
+pub fn gen(v: &[impl AsRef<[u8]>]) -> String {
+  let mut ctx = Context::new(&SHA256);
+  for src in v {
+    ctx.update(src.as_ref());
+  }
+  let digest = ctx.finish();
+  let out: Vec<String> = digest
+    .as_ref()
+    .iter()
+    .map(|byte| format!("{:02x}", byte))
+    .collect();
+  out.join("")
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_gen() {
+    let actual = gen(&[b"hello world"]);
+    assert_eq!(
+      actual,
+      "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9"
+    );
+  }
+}
diff --git a/cli/util/diff.rs b/cli/util/diff.rs
new file mode 100644
index 000000000..048464162
--- /dev/null
+++ b/cli/util/diff.rs
@@ -0,0 +1,227 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use crate::colors;
+use dissimilar::{diff as difference, Chunk};
+use std::fmt::Write as _;
+
+/// Print diff of the same file_path, before and after formatting.
+///
+/// Diff format is loosely based on GitHub diff formatting.
+pub fn diff(orig_text: &str, edit_text: &str) -> String {
+  if orig_text == edit_text {
+    return String::new();
+  }
+
+  // normalize newlines as it adds too much noise if they differ
+  let orig_text = orig_text.replace("\r\n", "\n");
+  let edit_text = edit_text.replace("\r\n", "\n");
+
+  if orig_text == edit_text {
+    return " | Text differed by line endings.\n".to_string();
+  }
+
+  DiffBuilder::build(&orig_text, &edit_text)
+}
+
+struct DiffBuilder {
+  output: String,
+  line_number_width: usize,
+  orig_line: usize,
+  edit_line: usize,
+  orig: String,
+  edit: String,
+  has_changes: bool,
+}
+
+impl DiffBuilder {
+  pub fn build(orig_text: &str, edit_text: &str) -> String {
+    let mut diff_builder = DiffBuilder {
+      output: String::new(),
+      orig_line: 1,
+      edit_line: 1,
+      orig: String::new(),
+      edit: String::new(),
+      has_changes: false,
+      line_number_width: {
+        let line_count = std::cmp::max(
+          orig_text.split('\n').count(),
+          edit_text.split('\n').count(),
+        );
+        line_count.to_string().chars().count()
+      },
+    };
+
+    let chunks = difference(orig_text, edit_text);
+    diff_builder.handle_chunks(chunks);
+    diff_builder.output
+  }
+
+  fn handle_chunks<'a>(&'a mut self, chunks: Vec<Chunk<'a>>) {
+    for chunk in chunks {
+      match chunk {
+        Chunk::Delete(s) => {
+          let split = s.split('\n').enumerate();
+          for (i, s) in split {
+            if i > 0 {
+              self.orig.push('\n');
+            }
+            self.orig.push_str(&fmt_rem_text_highlight(s));
+          }
+          self.has_changes = true
+        }
+        Chunk::Insert(s) => {
+          let split = s.split('\n').enumerate();
+          for (i, s) in split {
+            if i > 0 {
+              self.edit.push('\n');
+            }
+            self.edit.push_str(&fmt_add_text_highlight(s));
+          }
+          self.has_changes = true
+        }
+        Chunk::Equal(s) => {
+          let split = s.split('\n').enumerate();
+          for (i, s) in split {
+            if i > 0 {
+              self.flush_changes();
+            }
+            self.orig.push_str(&fmt_rem_text(s));
+            self.edit.push_str(&fmt_add_text(s));
+          }
+        }
+      }
+    }
+
+    self.flush_changes();
+  }
+
+  fn flush_changes(&mut self) {
+    if self.has_changes {
+      self.write_line_diff();
+
+      self.orig_line += self.orig.split('\n').count();
+      self.edit_line += self.edit.split('\n').count();
+      self.has_changes = false;
+    } else {
+      self.orig_line += 1;
+      self.edit_line += 1;
+    }
+
+    self.orig.clear();
+    self.edit.clear();
+  }
+
+  fn write_line_diff(&mut self) {
+    let split = self.orig.split('\n').enumerate();
+    for (i, s) in split {
+      write!(
+        self.output,
+        "{:width$}{} ",
+        self.orig_line + i,
+        colors::gray(" |"),
+        width = self.line_number_width
+      )
+      .unwrap();
+      self.output.push_str(&fmt_rem());
+      self.output.push_str(s);
+      self.output.push('\n');
+    }
+
+    let split = self.edit.split('\n').enumerate();
+    for (i, s) in split {
+      write!(
+        self.output,
+        "{:width$}{} ",
+        self.edit_line + i,
+        colors::gray(" |"),
+        width = self.line_number_width
+      )
+      .unwrap();
+      self.output.push_str(&fmt_add());
+      self.output.push_str(s);
+      self.output.push('\n');
+    }
+  }
+}
+
+fn fmt_add() -> String {
+  colors::green_bold("+").to_string()
+}
+
+fn fmt_add_text(x: &str) -> String {
+  colors::green(x).to_string()
+}
+
+fn fmt_add_text_highlight(x: &str) -> String {
+  colors::black_on_green(x).to_string()
+}
+
+fn fmt_rem() -> String {
+  colors::red_bold("-").to_string()
+}
+
+fn fmt_rem_text(x: &str) -> String {
+  colors::red(x).to_string()
+}
+
+fn fmt_rem_text_highlight(x: &str) -> String {
+  colors::white_on_red(x).to_string()
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_diff() {
+    run_test(
+      "console.log('Hello World')",
+      "console.log(\"Hello World\");",
+      concat!(
+        "1 | -console.log('Hello World')\n",
+        "1 | +console.log(\"Hello World\");\n",
+      ),
+    );
+
+    run_test(
+      "\n\n\n\nconsole.log(\n'Hello World'\n)",
+      "console.log(\n\"Hello World\"\n);",
+      concat!(
+        "1 | -\n",
+        "2 | -\n",
+        "3 | -\n",
+        "4 | -\n",
+        "5 | -console.log(\n",
+        "1 | +console.log(\n",
+        "6 | -'Hello World'\n",
+        "2 | +\"Hello World\"\n",
+        "7 | -)\n3 | +);\n",
+      ),
+    );
+  }
+
+  #[test]
+  fn test_eof_newline_missing() {
+    run_test(
+      "test\nsome line text test",
+      "test\nsome line text test\n",
+      concat!(
+        "2 | -some line text test\n",
+        "2 | +some line text test\n",
+        "3 | +\n",
+      ),
+    );
+  }
+
+  #[test]
+  fn test_newlines_differing() {
+    run_test("test\n", "test\r\n", " | Text differed by line endings.\n");
+  }
+
+  fn run_test(diff_text1: &str, diff_text2: &str, expected_output: &str) {
+    assert_eq!(
+      test_util::strip_ansi_codes(&diff(diff_text1, diff_text2,)),
+      expected_output,
+    );
+  }
+}
diff --git a/cli/util/display.rs b/cli/util/display.rs
new file mode 100644
index 000000000..f13965e28
--- /dev/null
+++ b/cli/util/display.rs
@@ -0,0 +1,97 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use deno_core::error::AnyError;
+use deno_core::serde_json;
+use std::io::Write;
+
+/// A function that converts a float to a string the represents a human
+/// readable version of that number.
+pub fn human_size(size: f64) -> String {
+  let negative = if size.is_sign_positive() { "" } else { "-" };
+  let size = size.abs();
+  let units = ["B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
+  if size < 1_f64 {
+    return format!("{}{}{}", negative, size, "B");
+  }
+  let delimiter = 1024_f64;
+  let exponent = std::cmp::min(
+    (size.ln() / delimiter.ln()).floor() as i32,
+    (units.len() - 1) as i32,
+  );
+  let pretty_bytes = format!("{:.2}", size / delimiter.powi(exponent))
+    .parse::<f64>()
+    .unwrap()
+    * 1_f64;
+  let unit = units[exponent as usize];
+  format!("{}{}{}", negative, pretty_bytes, unit)
+}
+
+/// A function that converts a milisecond elapsed time to a string that
+/// represents a human readable version of that time.
+pub fn human_elapsed(elapsed: u128) -> String {
+  if elapsed < 1_000 {
+    return format!("{}ms", elapsed);
+  }
+  if elapsed < 1_000 * 60 {
+    return format!("{}s", elapsed / 1000);
+  }
+
+  let seconds = elapsed / 1_000;
+  let minutes = seconds / 60;
+  let seconds_remainder = seconds % 60;
+  format!("{}m{}s", minutes, seconds_remainder)
+}
+
+pub fn write_to_stdout_ignore_sigpipe(
+  bytes: &[u8],
+) -> Result<(), std::io::Error> {
+  use std::io::ErrorKind;
+
+  match std::io::stdout().write_all(bytes) {
+    Ok(()) => Ok(()),
+    Err(e) => match e.kind() {
+      ErrorKind::BrokenPipe => Ok(()),
+      _ => Err(e),
+    },
+  }
+}
+
+pub fn write_json_to_stdout<T>(value: &T) -> Result<(), AnyError>
+where
+  T: ?Sized + serde::ser::Serialize,
+{
+  let mut writer = std::io::BufWriter::new(std::io::stdout());
+  serde_json::to_writer_pretty(&mut writer, value)?;
+  writeln!(&mut writer)?;
+  Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_human_size() {
+    assert_eq!(human_size(1_f64), "1B");
+    assert_eq!(human_size((12 * 1024) as f64), "12KB");
+    assert_eq!(human_size((24_i64 * 1024 * 1024) as f64), "24MB");
+    assert_eq!(human_size((24_i64 * 1024 * 1024 * 1024) as f64), "24GB");
+    assert_eq!(
+      human_size((24_i64 * 1024 * 1024 * 1024 * 1024) as f64),
+      "24TB"
+    );
+    assert_eq!(human_size(0_f64), "0B");
+    assert_eq!(human_size(-10_f64), "-10B");
+  }
+
+  #[test]
+  fn test_human_elapsed() {
+    assert_eq!(human_elapsed(1), "1ms");
+    assert_eq!(human_elapsed(256), "256ms");
+    assert_eq!(human_elapsed(1000), "1s");
+    assert_eq!(human_elapsed(1001), "1s");
+    assert_eq!(human_elapsed(1020), "1s");
+    assert_eq!(human_elapsed(70 * 1000), "1m10s");
+    assert_eq!(human_elapsed(86 * 1000 + 100), "1m26s");
+  }
+}
diff --git a/cli/util/file_watcher.rs b/cli/util/file_watcher.rs
new file mode 100644
index 000000000..5158437a0
--- /dev/null
+++ b/cli/util/file_watcher.rs
@@ -0,0 +1,374 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use crate::colors;
+use crate::util::fs::canonicalize_path;
+
+use deno_core::error::AnyError;
+use deno_core::error::JsError;
+use deno_core::futures::Future;
+use deno_runtime::fmt_errors::format_js_error;
+use log::info;
+use notify::event::Event as NotifyEvent;
+use notify::event::EventKind;
+use notify::Error as NotifyError;
+use notify::RecommendedWatcher;
+use notify::RecursiveMode;
+use notify::Watcher;
+use std::collections::HashSet;
+use std::path::PathBuf;
+use std::sync::Arc;
+use std::time::Duration;
+use tokio::select;
+use tokio::sync::mpsc;
+use tokio::sync::mpsc::UnboundedReceiver;
+use tokio::time::sleep;
+
+const CLEAR_SCREEN: &str = "\x1B[2J\x1B[1;1H";
+const DEBOUNCE_INTERVAL: Duration = Duration::from_millis(200);
+
+struct DebouncedReceiver {
+  // The `recv()` call could be used in a tokio `select!` macro,
+  // and so we store this state on the struct to ensure we don't
+  // lose items if a `recv()` never completes
+  received_items: HashSet<PathBuf>,
+  receiver: UnboundedReceiver<Vec<PathBuf>>,
+}
+
+impl DebouncedReceiver {
+  fn new_with_sender() -> (Arc<mpsc::UnboundedSender<Vec<PathBuf>>>, Self) {
+    let (sender, receiver) = mpsc::unbounded_channel();
+    (
+      Arc::new(sender),
+      Self {
+        receiver,
+        received_items: HashSet::new(),
+      },
+    )
+  }
+
+  async fn recv(&mut self) -> Option<Vec<PathBuf>> {
+    if self.received_items.is_empty() {
+      self
+        .received_items
+        .extend(self.receiver.recv().await?.into_iter());
+    }
+
+    loop {
+      select! {
+        items = self.receiver.recv() => {
+          self.received_items.extend(items?);
+        }
+        _ = sleep(DEBOUNCE_INTERVAL) => {
+          return Some(self.received_items.drain().collect());
+        }
+      }
+    }
+  }
+}
+
+async fn error_handler<F>(watch_future: F)
+where
+  F: Future<Output = Result<(), AnyError>>,
+{
+  let result = watch_future.await;
+  if let Err(err) = result {
+    let error_string = match err.downcast_ref::<JsError>() {
+      Some(e) => format_js_error(e),
+      None => format!("{:?}", err),
+    };
+    eprintln!(
+      "{}: {}",
+      colors::red_bold("error"),
+      error_string.trim_start_matches("error: ")
+    );
+  }
+}
+
+pub enum ResolutionResult<T> {
+  Restart {
+    paths_to_watch: Vec<PathBuf>,
+    result: Result<T, AnyError>,
+  },
+  Ignore,
+}
+
+async fn next_restart<R, T, F>(
+  resolver: &mut R,
+  debounced_receiver: &mut DebouncedReceiver,
+) -> (Vec<PathBuf>, Result<T, AnyError>)
+where
+  R: FnMut(Option<Vec<PathBuf>>) -> F,
+  F: Future<Output = ResolutionResult<T>>,
+{
+  loop {
+    let changed = debounced_receiver.recv().await;
+    match resolver(changed).await {
+      ResolutionResult::Ignore => {
+        log::debug!("File change ignored")
+      }
+      ResolutionResult::Restart {
+        paths_to_watch,
+        result,
+      } => {
+        return (paths_to_watch, result);
+      }
+    }
+  }
+}
+
+pub struct PrintConfig {
+  /// printing watcher status to terminal.
+  pub job_name: String,
+  /// determine whether to clear the terminal screen
+  pub clear_screen: bool,
+}
+
+fn create_print_after_restart_fn(clear_screen: bool) -> impl Fn() {
+  move || {
+    if clear_screen {
+      eprint!("{}", CLEAR_SCREEN);
+    }
+    info!(
+      "{} File change detected! Restarting!",
+      colors::intense_blue("Watcher"),
+    );
+  }
+}
+
+/// Creates a file watcher, which will call `resolver` with every file change.
+///
+/// - `resolver` is used for resolving file paths to be watched at every restarting
+/// of the watcher, and can also return a value to be passed to `operation`.
+/// It returns a [`ResolutionResult`], which can either instruct the watcher to restart or ignore the change.
+/// This always contains paths to watch;
+///
+/// - `operation` is the actual operation we want to run every time the watcher detects file
+/// changes. For example, in the case where we would like to bundle, then `operation` would
+/// have the logic for it like bundling the code.
+pub async fn watch_func<R, O, T, F1, F2>(
+  mut resolver: R,
+  mut operation: O,
+  print_config: PrintConfig,
+) -> Result<(), AnyError>
+where
+  R: FnMut(Option<Vec<PathBuf>>) -> F1,
+  O: FnMut(T) -> F2,
+  F1: Future<Output = ResolutionResult<T>>,
+  F2: Future<Output = Result<(), AnyError>>,
+{
+  let (sender, mut receiver) = DebouncedReceiver::new_with_sender();
+
+  let PrintConfig {
+    job_name,
+    clear_screen,
+  } = print_config;
+
+  // Store previous data. If module resolution fails at some point, the watcher will try to
+  // continue watching files using these data.
+  let mut paths_to_watch;
+  let mut resolution_result;
+
+  let print_after_restart = create_print_after_restart_fn(clear_screen);
+
+  match resolver(None).await {
+    ResolutionResult::Ignore => {
+      // The only situation where it makes sense to ignore the initial 'change'
+      // is if the command isn't supposed to do anything until something changes,
+      // e.g. a variant of `deno test` which doesn't run the entire test suite to start with,
+      // but instead does nothing until you make a change.
+      //
+      // In that case, this is probably the correct output.
+      info!(
+        "{} Waiting for file changes...",
+        colors::intense_blue("Watcher"),
+      );
+
+      let (paths, result) = next_restart(&mut resolver, &mut receiver).await;
+      paths_to_watch = paths;
+      resolution_result = result;
+
+      print_after_restart();
+    }
+    ResolutionResult::Restart {
+      paths_to_watch: paths,
+      result,
+    } => {
+      paths_to_watch = paths;
+      resolution_result = result;
+    }
+  };
+
+  info!("{} {} started.", colors::intense_blue("Watcher"), job_name,);
+
+  loop {
+    let mut watcher = new_watcher(sender.clone())?;
+    add_paths_to_watcher(&mut watcher, &paths_to_watch);
+
+    match resolution_result {
+      Ok(operation_arg) => {
+        let fut = error_handler(operation(operation_arg));
+        select! {
+          (paths, result) = next_restart(&mut resolver, &mut receiver) => {
+            if result.is_ok() {
+              paths_to_watch = paths;
+            }
+            resolution_result = result;
+
+            print_after_restart();
+            continue;
+          },
+          _ = fut => {},
+        };
+
+        info!(
+          "{} {} finished. Restarting on file change...",
+          colors::intense_blue("Watcher"),
+          job_name,
+        );
+      }
+      Err(error) => {
+        eprintln!("{}: {}", colors::red_bold("error"), error);
+        info!(
+          "{} {} failed. Restarting on file change...",
+          colors::intense_blue("Watcher"),
+          job_name,
+        );
+      }
+    }
+
+    let (paths, result) = next_restart(&mut resolver, &mut receiver).await;
+    if result.is_ok() {
+      paths_to_watch = paths;
+    }
+    resolution_result = result;
+
+    print_after_restart();
+
+    drop(watcher);
+  }
+}
+
+/// Creates a file watcher.
+///
+/// - `operation` is the actual operation we want to run every time the watcher detects file
+/// changes. For example, in the case where we would like to bundle, then `operation` would
+/// have the logic for it like bundling the code.
+pub async fn watch_func2<T: Clone, O, F>(
+  mut paths_to_watch_receiver: UnboundedReceiver<Vec<PathBuf>>,
+  mut operation: O,
+  operation_args: T,
+  print_config: PrintConfig,
+) -> Result<(), AnyError>
+where
+  O: FnMut(T) -> Result<F, AnyError>,
+  F: Future<Output = Result<(), AnyError>>,
+{
+  let (watcher_sender, mut watcher_receiver) =
+    DebouncedReceiver::new_with_sender();
+
+  let PrintConfig {
+    job_name,
+    clear_screen,
+  } = print_config;
+
+  let print_after_restart = create_print_after_restart_fn(clear_screen);
+
+  info!("{} {} started.", colors::intense_blue("Watcher"), job_name,);
+
+  fn consume_paths_to_watch(
+    watcher: &mut RecommendedWatcher,
+    receiver: &mut UnboundedReceiver<Vec<PathBuf>>,
+  ) {
+    loop {
+      match receiver.try_recv() {
+        Ok(paths) => {
+          add_paths_to_watcher(watcher, &paths);
+        }
+        Err(e) => match e {
+          mpsc::error::TryRecvError::Empty => {
+            break;
+          }
+          // there must be at least one receiver alive
+          _ => unreachable!(),
+        },
+      }
+    }
+  }
+
+  loop {
+    let mut watcher = new_watcher(watcher_sender.clone())?;
+    consume_paths_to_watch(&mut watcher, &mut paths_to_watch_receiver);
+
+    let receiver_future = async {
+      loop {
+        let maybe_paths = paths_to_watch_receiver.recv().await;
+        add_paths_to_watcher(&mut watcher, &maybe_paths.unwrap());
+      }
+    };
+    let operation_future = error_handler(operation(operation_args.clone())?);
+
+    select! {
+      _ = receiver_future => {},
+      _ = watcher_receiver.recv() => {
+        print_after_restart();
+        continue;
+      },
+      _ = operation_future => {
+        // TODO(bartlomieju): print exit code here?
+        info!(
+          "{} {} finished. Restarting on file change...",
+          colors::intense_blue("Watcher"),
+          job_name,
+        );
+        consume_paths_to_watch(&mut watcher, &mut paths_to_watch_receiver);
+      },
+    };
+
+    let receiver_future = async {
+      loop {
+        let maybe_paths = paths_to_watch_receiver.recv().await;
+        add_paths_to_watcher(&mut watcher, &maybe_paths.unwrap());
+      }
+    };
+    select! {
+      _ = receiver_future => {},
+      _ = watcher_receiver.recv() => {
+        print_after_restart();
+        continue;
+      },
+    };
+  }
+}
+
+fn new_watcher(
+  sender: Arc<mpsc::UnboundedSender<Vec<PathBuf>>>,
+) -> Result<RecommendedWatcher, AnyError> {
+  let watcher = Watcher::new(
+    move |res: Result<NotifyEvent, NotifyError>| {
+      if let Ok(event) = res {
+        if matches!(
+          event.kind,
+          EventKind::Create(_) | EventKind::Modify(_) | EventKind::Remove(_)
+        ) {
+          let paths = event
+            .paths
+            .iter()
+            .filter_map(|path| canonicalize_path(path).ok())
+            .collect();
+          sender.send(paths).unwrap();
+        }
+      }
+    },
+    Default::default(),
+  )?;
+
+  Ok(watcher)
+}
+
+fn add_paths_to_watcher(watcher: &mut RecommendedWatcher, paths: &[PathBuf]) {
+  // Ignore any error e.g. `PathNotFound`
+  for path in paths {
+    let _ = watcher.watch(path, RecursiveMode::Recursive);
+  }
+  log::debug!("Watching paths: {:?}", paths);
+}
diff --git a/cli/util/fs.rs b/cli/util/fs.rs
new file mode 100644
index 000000000..35cdae4fa
--- /dev/null
+++ b/cli/util/fs.rs
@@ -0,0 +1,661 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use deno_core::anyhow::Context;
+use deno_core::error::AnyError;
+pub use deno_core::normalize_path;
+use deno_core::ModuleSpecifier;
+use deno_runtime::deno_crypto::rand;
+use deno_runtime::deno_node::PathClean;
+use std::env::current_dir;
+use std::fs::OpenOptions;
+use std::io::Error;
+use std::io::ErrorKind;
+use std::io::Write;
+use std::path::Path;
+use std::path::PathBuf;
+use std::time::Duration;
+use walkdir::WalkDir;
+
+use super::path::specifier_to_file_path;
+
+pub fn atomic_write_file<T: AsRef<[u8]>>(
+  filename: &Path,
+  data: T,
+  mode: u32,
+) -> std::io::Result<()> {
+  let rand: String = (0..4)
+    .map(|_| format!("{:02x}", rand::random::<u8>()))
+    .collect();
+  let extension = format!("{}.tmp", rand);
+  let tmp_file = filename.with_extension(extension);
+  write_file(&tmp_file, data, mode)?;
+  std::fs::rename(tmp_file, filename)?;
+  Ok(())
+}
+
+pub fn write_file<T: AsRef<[u8]>>(
+  filename: &Path,
+  data: T,
+  mode: u32,
+) -> std::io::Result<()> {
+  write_file_2(filename, data, true, mode, true, false)
+}
+
+pub fn write_file_2<T: AsRef<[u8]>>(
+  filename: &Path,
+  data: T,
+  update_mode: bool,
+  mode: u32,
+  is_create: bool,
+  is_append: bool,
+) -> std::io::Result<()> {
+  let mut file = OpenOptions::new()
+    .read(false)
+    .write(true)
+    .append(is_append)
+    .truncate(!is_append)
+    .create(is_create)
+    .open(filename)?;
+
+  if update_mode {
+    #[cfg(unix)]
+    {
+      use std::os::unix::fs::PermissionsExt;
+      let mode = mode & 0o777;
+      let permissions = PermissionsExt::from_mode(mode);
+      file.set_permissions(permissions)?;
+    }
+    #[cfg(not(unix))]
+    let _ = mode;
+  }
+
+  file.write_all(data.as_ref())
+}
+
+/// Similar to `std::fs::canonicalize()` but strips UNC prefixes on Windows.
+pub fn canonicalize_path(path: &Path) -> Result<PathBuf, Error> {
+  let path = path.canonicalize()?;
+  #[cfg(windows)]
+  return Ok(strip_unc_prefix(path));
+  #[cfg(not(windows))]
+  return Ok(path);
+}
+
+/// Canonicalizes a path which might be non-existent by going up the
+/// ancestors until it finds a directory that exists, canonicalizes
+/// that path, then adds back the remaining path components.
+///
+/// Note: When using this, you should be aware that a symlink may
+/// subsequently be created along this path by some other code.
+pub fn canonicalize_path_maybe_not_exists(
+  path: &Path,
+) -> Result<PathBuf, Error> {
+  let path = path.to_path_buf().clean();
+  let mut path = path.as_path();
+  let mut names_stack = Vec::new();
+  loop {
+    match canonicalize_path(path) {
+      Ok(mut canonicalized_path) => {
+        for name in names_stack.into_iter().rev() {
+          canonicalized_path = canonicalized_path.join(name);
+        }
+        return Ok(canonicalized_path);
+      }
+      Err(err) if err.kind() == ErrorKind::NotFound => {
+        names_stack.push(path.file_name().unwrap());
+        path = path.parent().unwrap();
+      }
+      Err(err) => return Err(err),
+    }
+  }
+}
+
+#[cfg(windows)]
+fn strip_unc_prefix(path: PathBuf) -> PathBuf {
+  use std::path::Component;
+  use std::path::Prefix;
+
+  let mut components = path.components();
+  match components.next() {
+    Some(Component::Prefix(prefix)) => {
+      match prefix.kind() {
+        // \\?\device
+        Prefix::Verbatim(device) => {
+          let mut path = PathBuf::new();
+          path.push(format!(r"\\{}\", device.to_string_lossy()));
+          path.extend(components.filter(|c| !matches!(c, Component::RootDir)));
+          path
+        }
+        // \\?\c:\path
+        Prefix::VerbatimDisk(_) => {
+          let mut path = PathBuf::new();
+          path.push(prefix.as_os_str().to_string_lossy().replace(r"\\?\", ""));
+          path.extend(components);
+          path
+        }
+        // \\?\UNC\hostname\share_name\path
+        Prefix::VerbatimUNC(hostname, share_name) => {
+          let mut path = PathBuf::new();
+          path.push(format!(
+            r"\\{}\{}\",
+            hostname.to_string_lossy(),
+            share_name.to_string_lossy()
+          ));
+          path.extend(components.filter(|c| !matches!(c, Component::RootDir)));
+          path
+        }
+        _ => path,
+      }
+    }
+    _ => path,
+  }
+}
+
+pub fn resolve_from_cwd(path: &Path) -> Result<PathBuf, AnyError> {
+  let resolved_path = if path.is_absolute() {
+    path.to_owned()
+  } else {
+    let cwd =
+      current_dir().context("Failed to get current working directory")?;
+    cwd.join(path)
+  };
+
+  Ok(normalize_path(&resolved_path))
+}
+
+/// Collects file paths that satisfy the given predicate, by recursively walking `files`.
+/// If the walker visits a path that is listed in `ignore`, it skips descending into the directory.
+pub fn collect_files<P>(
+  files: &[PathBuf],
+  ignore: &[PathBuf],
+  predicate: P,
+) -> Result<Vec<PathBuf>, AnyError>
+where
+  P: Fn(&Path) -> bool,
+{
+  let mut target_files = Vec::new();
+
+  // retain only the paths which exist and ignore the rest
+  let canonicalized_ignore: Vec<PathBuf> = ignore
+    .iter()
+    .filter_map(|i| canonicalize_path(i).ok())
+    .collect();
+
+  for file in files {
+    for entry in WalkDir::new(file)
+      .into_iter()
+      .filter_entry(|e| {
+        canonicalize_path(e.path()).map_or(false, |c| {
+          !canonicalized_ignore.iter().any(|i| c.starts_with(i))
+        })
+      })
+      .filter_map(|e| match e {
+        Ok(e) if !e.file_type().is_dir() && predicate(e.path()) => Some(e),
+        _ => None,
+      })
+    {
+      target_files.push(canonicalize_path(entry.path())?)
+    }
+  }
+
+  Ok(target_files)
+}
+
+/// Collects module specifiers that satisfy the given predicate as a file path, by recursively walking `include`.
+/// Specifiers that start with http and https are left intact.
+pub fn collect_specifiers<P>(
+  include: Vec<String>,
+  ignore: &[PathBuf],
+  predicate: P,
+) -> Result<Vec<ModuleSpecifier>, AnyError>
+where
+  P: Fn(&Path) -> bool,
+{
+  let mut prepared = vec![];
+
+  let root_path = current_dir()?;
+  for path in include {
+    let lowercase_path = path.to_lowercase();
+    if lowercase_path.starts_with("http://")
+      || lowercase_path.starts_with("https://")
+    {
+      let url = ModuleSpecifier::parse(&path)?;
+      prepared.push(url);
+      continue;
+    }
+
+    let p = if lowercase_path.starts_with("file://") {
+      specifier_to_file_path(&ModuleSpecifier::parse(&path)?)?
+    } else {
+      root_path.join(path)
+    };
+    let p = normalize_path(&p);
+    if p.is_dir() {
+      let test_files = collect_files(&[p], ignore, &predicate).unwrap();
+      let mut test_files_as_urls = test_files
+        .iter()
+        .map(|f| ModuleSpecifier::from_file_path(f).unwrap())
+        .collect::<Vec<ModuleSpecifier>>();
+
+      test_files_as_urls.sort();
+      prepared.extend(test_files_as_urls);
+    } else {
+      let url = ModuleSpecifier::from_file_path(p).unwrap();
+      prepared.push(url);
+    }
+  }
+
+  Ok(prepared)
+}
+
+/// Asynchronously removes a directory and all its descendants, but does not error
+/// when the directory does not exist.
+pub async fn remove_dir_all_if_exists(path: &Path) -> std::io::Result<()> {
+  let result = tokio::fs::remove_dir_all(path).await;
+  match result {
+    Err(err) if err.kind() == std::io::ErrorKind::NotFound => Ok(()),
+    _ => result,
+  }
+}
+
+/// Copies a directory to another directory.
+///
+/// Note: Does not handle symlinks.
+pub fn copy_dir_recursive(from: &Path, to: &Path) -> Result<(), AnyError> {
+  std::fs::create_dir_all(to)
+    .with_context(|| format!("Creating {}", to.display()))?;
+  let read_dir = std::fs::read_dir(from)
+    .with_context(|| format!("Reading {}", from.display()))?;
+
+  for entry in read_dir {
+    let entry = entry?;
+    let file_type = entry.file_type()?;
+    let new_from = from.join(entry.file_name());
+    let new_to = to.join(entry.file_name());
+
+    if file_type.is_dir() {
+      copy_dir_recursive(&new_from, &new_to).with_context(|| {
+        format!("Dir {} to {}", new_from.display(), new_to.display())
+      })?;
+    } else if file_type.is_file() {
+      std::fs::copy(&new_from, &new_to).with_context(|| {
+        format!("Copying {} to {}", new_from.display(), new_to.display())
+      })?;
+    }
+  }
+
+  Ok(())
+}
+
+/// Hardlinks the files in one directory to another directory.
+///
+/// Note: Does not handle symlinks.
+pub fn hard_link_dir_recursive(from: &Path, to: &Path) -> Result<(), AnyError> {
+  std::fs::create_dir_all(to)
+    .with_context(|| format!("Creating {}", to.display()))?;
+  let read_dir = std::fs::read_dir(from)
+    .with_context(|| format!("Reading {}", from.display()))?;
+
+  for entry in read_dir {
+    let entry = entry?;
+    let file_type = entry.file_type()?;
+    let new_from = from.join(entry.file_name());
+    let new_to = to.join(entry.file_name());
+
+    if file_type.is_dir() {
+      hard_link_dir_recursive(&new_from, &new_to).with_context(|| {
+        format!("Dir {} to {}", new_from.display(), new_to.display())
+      })?;
+    } else if file_type.is_file() {
+      // note: chance for race conditions here between attempting to create,
+      // then removing, then attempting to create. There doesn't seem to be
+      // a way to hard link with overwriting in Rust, but maybe there is some
+      // way with platform specific code. The workaround here is to handle
+      // scenarios where something else might create or remove files.
+      if let Err(err) = std::fs::hard_link(&new_from, &new_to) {
+        if err.kind() == ErrorKind::AlreadyExists {
+          if let Err(err) = std::fs::remove_file(&new_to) {
+            if err.kind() == ErrorKind::NotFound {
+              // Assume another process/thread created this hard link to the file we are wanting
+              // to remove then sleep a little bit to let the other process/thread move ahead
+              // faster to reduce contention.
+              std::thread::sleep(Duration::from_millis(10));
+            } else {
+              return Err(err).with_context(|| {
+                format!(
+                  "Removing file to hard link {} to {}",
+                  new_from.display(),
+                  new_to.display()
+                )
+              });
+            }
+          }
+
+          // Always attempt to recreate the hardlink. In contention scenarios, the other process
+          // might have been killed or exited after removing the file, but before creating the hardlink
+          if let Err(err) = std::fs::hard_link(&new_from, &new_to) {
+            // Assume another process/thread created this hard link to the file we are wanting
+            // to now create then sleep a little bit to let the other process/thread move ahead
+            // faster to reduce contention.
+            if err.kind() == ErrorKind::AlreadyExists {
+              std::thread::sleep(Duration::from_millis(10));
+            } else {
+              return Err(err).with_context(|| {
+                format!(
+                  "Hard linking {} to {}",
+                  new_from.display(),
+                  new_to.display()
+                )
+              });
+            }
+          }
+        } else {
+          return Err(err).with_context(|| {
+            format!(
+              "Hard linking {} to {}",
+              new_from.display(),
+              new_to.display()
+            )
+          });
+        }
+      }
+    }
+  }
+
+  Ok(())
+}
+
+pub fn symlink_dir(oldpath: &Path, newpath: &Path) -> Result<(), AnyError> {
+  let err_mapper = |err: Error| {
+    Error::new(
+      err.kind(),
+      format!(
+        "{}, symlink '{}' -> '{}'",
+        err,
+        oldpath.display(),
+        newpath.display()
+      ),
+    )
+  };
+  #[cfg(unix)]
+  {
+    use std::os::unix::fs::symlink;
+    symlink(oldpath, newpath).map_err(err_mapper)?;
+  }
+  #[cfg(not(unix))]
+  {
+    use std::os::windows::fs::symlink_dir;
+    symlink_dir(oldpath, newpath).map_err(err_mapper)?;
+  }
+  Ok(())
+}
+
+/// Gets the total size (in bytes) of a directory.
+pub fn dir_size(path: &Path) -> std::io::Result<u64> {
+  let entries = std::fs::read_dir(path)?;
+  let mut total = 0;
+  for entry in entries {
+    let entry = entry?;
+    total += match entry.metadata()? {
+      data if data.is_dir() => dir_size(&entry.path())?,
+      data => data.len(),
+    };
+  }
+  Ok(total)
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+  use test_util::TempDir;
+
+  #[test]
+  fn resolve_from_cwd_child() {
+    let cwd = current_dir().unwrap();
+    assert_eq!(resolve_from_cwd(Path::new("a")).unwrap(), cwd.join("a"));
+  }
+
+  #[test]
+  fn resolve_from_cwd_dot() {
+    let cwd = current_dir().unwrap();
+    assert_eq!(resolve_from_cwd(Path::new(".")).unwrap(), cwd);
+  }
+
+  #[test]
+  fn resolve_from_cwd_parent() {
+    let cwd = current_dir().unwrap();
+    assert_eq!(resolve_from_cwd(Path::new("a/..")).unwrap(), cwd);
+  }
+
+  #[test]
+  fn test_normalize_path() {
+    assert_eq!(normalize_path(Path::new("a/../b")), PathBuf::from("b"));
+    assert_eq!(normalize_path(Path::new("a/./b/")), PathBuf::from("a/b/"));
+    assert_eq!(
+      normalize_path(Path::new("a/./b/../c")),
+      PathBuf::from("a/c")
+    );
+
+    if cfg!(windows) {
+      assert_eq!(
+        normalize_path(Path::new("C:\\a\\.\\b\\..\\c")),
+        PathBuf::from("C:\\a\\c")
+      );
+    }
+  }
+
+  // TODO: Get a good expected value here for Windows.
+  #[cfg(not(windows))]
+  #[test]
+  fn resolve_from_cwd_absolute() {
+    let expected = Path::new("/a");
+    assert_eq!(resolve_from_cwd(expected).unwrap(), expected);
+  }
+
+  #[test]
+  fn test_collect_files() {
+    fn create_files(dir_path: &Path, files: &[&str]) {
+      std::fs::create_dir(dir_path).expect("Failed to create directory");
+      for f in files {
+        let path = dir_path.join(f);
+        std::fs::write(path, "").expect("Failed to create file");
+      }
+    }
+
+    // dir.ts
+    // ├── a.ts
+    // ├── b.js
+    // ├── child
+    // │   ├── e.mjs
+    // │   ├── f.mjsx
+    // │   ├── .foo.TS
+    // │   └── README.md
+    // ├── c.tsx
+    // ├── d.jsx
+    // └── ignore
+    //     ├── g.d.ts
+    //     └── .gitignore
+
+    let t = TempDir::new();
+
+    let root_dir_path = t.path().join("dir.ts");
+    let root_dir_files = ["a.ts", "b.js", "c.tsx", "d.jsx"];
+    create_files(&root_dir_path, &root_dir_files);
+
+    let child_dir_path = root_dir_path.join("child");
+    let child_dir_files = ["e.mjs", "f.mjsx", ".foo.TS", "README.md"];
+    create_files(&child_dir_path, &child_dir_files);
+
+    let ignore_dir_path = root_dir_path.join("ignore");
+    let ignore_dir_files = ["g.d.ts", ".gitignore"];
+    create_files(&ignore_dir_path, &ignore_dir_files);
+
+    let result = collect_files(&[root_dir_path], &[ignore_dir_path], |path| {
+      // exclude dotfiles
+      path
+        .file_name()
+        .and_then(|f| f.to_str())
+        .map_or(false, |f| !f.starts_with('.'))
+    })
+    .unwrap();
+    let expected = [
+      "a.ts",
+      "b.js",
+      "e.mjs",
+      "f.mjsx",
+      "README.md",
+      "c.tsx",
+      "d.jsx",
+    ];
+    for e in expected.iter() {
+      assert!(result.iter().any(|r| r.ends_with(e)));
+    }
+    assert_eq!(result.len(), expected.len());
+  }
+
+  #[test]
+  fn test_collect_specifiers() {
+    fn create_files(dir_path: &Path, files: &[&str]) {
+      std::fs::create_dir(dir_path).expect("Failed to create directory");
+      for f in files {
+        let path = dir_path.join(f);
+        std::fs::write(path, "").expect("Failed to create file");
+      }
+    }
+
+    // dir.ts
+    // ├── a.ts
+    // ├── b.js
+    // ├── child
+    // │   ├── e.mjs
+    // │   ├── f.mjsx
+    // │   ├── .foo.TS
+    // │   └── README.md
+    // ├── c.tsx
+    // ├── d.jsx
+    // └── ignore
+    //     ├── g.d.ts
+    //     └── .gitignore
+
+    let t = TempDir::new();
+
+    let root_dir_path = t.path().join("dir.ts");
+    let root_dir_files = ["a.ts", "b.js", "c.tsx", "d.jsx"];
+    create_files(&root_dir_path, &root_dir_files);
+
+    let child_dir_path = root_dir_path.join("child");
+    let child_dir_files = ["e.mjs", "f.mjsx", ".foo.TS", "README.md"];
+    create_files(&child_dir_path, &child_dir_files);
+
+    let ignore_dir_path = root_dir_path.join("ignore");
+    let ignore_dir_files = ["g.d.ts", ".gitignore"];
+    create_files(&ignore_dir_path, &ignore_dir_files);
+
+    let predicate = |path: &Path| {
+      // exclude dotfiles
+      path
+        .file_name()
+        .and_then(|f| f.to_str())
+        .map_or(false, |f| !f.starts_with('.'))
+    };
+
+    let result = collect_specifiers(
+      vec![
+        "http://localhost:8080".to_string(),
+        root_dir_path.to_str().unwrap().to_string(),
+        "https://localhost:8080".to_string(),
+      ],
+      &[ignore_dir_path],
+      predicate,
+    )
+    .unwrap();
+
+    let root_dir_url = ModuleSpecifier::from_file_path(
+      canonicalize_path(&root_dir_path).unwrap(),
+    )
+    .unwrap()
+    .to_string();
+    let expected: Vec<ModuleSpecifier> = [
+      "http://localhost:8080",
+      &format!("{}/a.ts", root_dir_url),
+      &format!("{}/b.js", root_dir_url),
+      &format!("{}/c.tsx", root_dir_url),
+      &format!("{}/child/README.md", root_dir_url),
+      &format!("{}/child/e.mjs", root_dir_url),
+      &format!("{}/child/f.mjsx", root_dir_url),
+      &format!("{}/d.jsx", root_dir_url),
+      "https://localhost:8080",
+    ]
+    .iter()
+    .map(|f| ModuleSpecifier::parse(f).unwrap())
+    .collect::<Vec<_>>();
+
+    assert_eq!(result, expected);
+
+    let scheme = if cfg!(target_os = "windows") {
+      "file:///"
+    } else {
+      "file://"
+    };
+    let result = collect_specifiers(
+      vec![format!(
+        "{}{}",
+        scheme,
+        root_dir_path
+          .join("child")
+          .to_str()
+          .unwrap()
+          .replace('\\', "/")
+      )],
+      &[],
+      predicate,
+    )
+    .unwrap();
+
+    let expected: Vec<ModuleSpecifier> = [
+      &format!("{}/child/README.md", root_dir_url),
+      &format!("{}/child/e.mjs", root_dir_url),
+      &format!("{}/child/f.mjsx", root_dir_url),
+    ]
+    .iter()
+    .map(|f| ModuleSpecifier::parse(f).unwrap())
+    .collect::<Vec<_>>();
+
+    assert_eq!(result, expected);
+  }
+
+  #[cfg(windows)]
+  #[test]
+  fn test_strip_unc_prefix() {
+    run_test(r"C:\", r"C:\");
+    run_test(r"C:\test\file.txt", r"C:\test\file.txt");
+
+    run_test(r"\\?\C:\", r"C:\");
+    run_test(r"\\?\C:\test\file.txt", r"C:\test\file.txt");
+
+    run_test(r"\\.\C:\", r"\\.\C:\");
+    run_test(r"\\.\C:\Test\file.txt", r"\\.\C:\Test\file.txt");
+
+    run_test(r"\\?\UNC\localhost\", r"\\localhost");
+    run_test(r"\\?\UNC\localhost\c$\", r"\\localhost\c$");
+    run_test(
+      r"\\?\UNC\localhost\c$\Windows\file.txt",
+      r"\\localhost\c$\Windows\file.txt",
+    );
+    run_test(r"\\?\UNC\wsl$\deno.json", r"\\wsl$\deno.json");
+
+    run_test(r"\\?\server1", r"\\server1");
+    run_test(r"\\?\server1\e$\", r"\\server1\e$\");
+    run_test(
+      r"\\?\server1\e$\test\file.txt",
+      r"\\server1\e$\test\file.txt",
+    );
+
+    fn run_test(input: &str, expected: &str) {
+      assert_eq!(
+        strip_unc_prefix(PathBuf::from(input)),
+        PathBuf::from(expected)
+      );
+    }
+  }
+}
diff --git a/cli/util/logger.rs b/cli/util/logger.rs
new file mode 100644
index 000000000..caa027c04
--- /dev/null
+++ b/cli/util/logger.rs
@@ -0,0 +1,79 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use std::io::Write;
+
+struct CliLogger(env_logger::Logger);
+
+impl CliLogger {
+  pub fn new(logger: env_logger::Logger) -> Self {
+    Self(logger)
+  }
+
+  pub fn filter(&self) -> log::LevelFilter {
+    self.0.filter()
+  }
+}
+
+impl log::Log for CliLogger {
+  fn enabled(&self, metadata: &log::Metadata) -> bool {
+    self.0.enabled(metadata)
+  }
+
+  fn log(&self, record: &log::Record) {
+    if self.enabled(record.metadata()) {
+      self.0.log(record);
+    }
+  }
+
+  fn flush(&self) {
+    self.0.flush();
+  }
+}
+
+pub fn init(maybe_level: Option<log::Level>) {
+  let log_level = maybe_level.unwrap_or(log::Level::Info);
+  let logger = env_logger::Builder::from_env(
+    env_logger::Env::default()
+      .default_filter_or(log_level.to_level_filter().to_string()),
+  )
+  // https://github.com/denoland/deno/issues/6641
+  .filter_module("rustyline", log::LevelFilter::Off)
+  // wgpu crates (gfx_backend), have a lot of useless INFO and WARN logs
+  .filter_module("wgpu", log::LevelFilter::Error)
+  .filter_module("gfx", log::LevelFilter::Error)
+  // used to make available the lsp_debug which is then filtered out at runtime
+  // in the cli logger
+  .filter_module("deno::lsp::performance", log::LevelFilter::Debug)
+  .format(|buf, record| {
+    let mut target = record.target().to_string();
+    if let Some(line_no) = record.line() {
+      target.push(':');
+      target.push_str(&line_no.to_string());
+    }
+    if record.level() <= log::Level::Info
+      || (record.target() == "deno::lsp::performance"
+        && record.level() == log::Level::Debug)
+    {
+      // Print ERROR, WARN, INFO and lsp_debug logs as they are
+      writeln!(buf, "{}", record.args())
+    } else {
+      // Add prefix to DEBUG or TRACE logs
+      writeln!(
+        buf,
+        "{} RS - {} - {}",
+        record.level(),
+        target,
+        record.args()
+      )
+    }
+  })
+  .build();
+
+  let cli_logger = CliLogger::new(logger);
+  let max_level = cli_logger.filter();
+  let r = log::set_boxed_logger(Box::new(cli_logger));
+  if r.is_ok() {
+    log::set_max_level(max_level);
+  }
+  r.expect("Could not install logger.");
+}
diff --git a/cli/util/mod.rs b/cli/util/mod.rs
new file mode 100644
index 000000000..176991d32
--- /dev/null
+++ b/cli/util/mod.rs
@@ -0,0 +1,14 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+// Note: Only add code in this folder that has no application specific logic
+pub mod checksum;
+pub mod diff;
+pub mod display;
+pub mod file_watcher;
+pub mod fs;
+pub mod logger;
+pub mod path;
+pub mod progress_bar;
+pub mod text_encoding;
+pub mod unix;
+pub mod windows;
diff --git a/cli/util/path.rs b/cli/util/path.rs
new file mode 100644
index 000000000..6df982f4e
--- /dev/null
+++ b/cli/util/path.rs
@@ -0,0 +1,452 @@
+use std::borrow::Cow;
+use std::path::Path;
+use std::path::PathBuf;
+
+use deno_ast::ModuleSpecifier;
+use deno_core::error::uri_error;
+use deno_core::error::AnyError;
+
+/// Checks if the path has extension Deno supports.
+pub fn is_supported_ext(path: &Path) -> bool {
+  if let Some(ext) = get_extension(path) {
+    matches!(
+      ext.as_str(),
+      "ts" | "tsx" | "js" | "jsx" | "mjs" | "mts" | "cjs" | "cts"
+    )
+  } else {
+    false
+  }
+}
+
+/// Get the extension of a file in lowercase.
+pub fn get_extension(file_path: &Path) -> Option<String> {
+  return file_path
+    .extension()
+    .and_then(|e| e.to_str())
+    .map(|e| e.to_lowercase());
+}
+
+/// Attempts to convert a specifier to a file path. By default, uses the Url
+/// crate's `to_file_path()` method, but falls back to try and resolve unix-style
+/// paths on Windows.
+pub fn specifier_to_file_path(
+  specifier: &ModuleSpecifier,
+) -> Result<PathBuf, AnyError> {
+  let result = if cfg!(windows) {
+    match specifier.to_file_path() {
+      Ok(path) => Ok(path),
+      Err(()) => {
+        // This might be a unix-style path which is used in the tests even on Windows.
+        // Attempt to see if we can convert it to a `PathBuf`. This code should be removed
+        // once/if https://github.com/servo/rust-url/issues/730 is implemented.
+        if specifier.scheme() == "file"
+          && specifier.host().is_none()
+          && specifier.port().is_none()
+          && specifier.path_segments().is_some()
+        {
+          let path_str = specifier.path();
+          match String::from_utf8(
+            percent_encoding::percent_decode(path_str.as_bytes()).collect(),
+          ) {
+            Ok(path_str) => Ok(PathBuf::from(path_str)),
+            Err(_) => Err(()),
+          }
+        } else {
+          Err(())
+        }
+      }
+    }
+  } else {
+    specifier.to_file_path()
+  };
+  match result {
+    Ok(path) => Ok(path),
+    Err(()) => Err(uri_error(format!(
+      "Invalid file path.\n  Specifier: {}",
+      specifier
+    ))),
+  }
+}
+
+/// Ensures a specifier that will definitely be a directory has a trailing slash.
+pub fn ensure_directory_specifier(
+  mut specifier: ModuleSpecifier,
+) -> ModuleSpecifier {
+  let path = specifier.path();
+  if !path.ends_with('/') {
+    let new_path = format!("{}/", path);
+    specifier.set_path(&new_path);
+  }
+  specifier
+}
+
+/// Gets the parent of this module specifier.
+pub fn specifier_parent(specifier: &ModuleSpecifier) -> ModuleSpecifier {
+  let mut specifier = specifier.clone();
+  // don't use specifier.segments() because it will strip the leading slash
+  let mut segments = specifier.path().split('/').collect::<Vec<_>>();
+  if segments.iter().all(|s| s.is_empty()) {
+    return specifier;
+  }
+  if let Some(last) = segments.last() {
+    if last.is_empty() {
+      segments.pop();
+    }
+    segments.pop();
+    let new_path = format!("{}/", segments.join("/"));
+    specifier.set_path(&new_path);
+  }
+  specifier
+}
+
+/// `from.make_relative(to)` but with fixes.
+pub fn relative_specifier(
+  from: &ModuleSpecifier,
+  to: &ModuleSpecifier,
+) -> Option<String> {
+  let is_dir = to.path().ends_with('/');
+
+  if is_dir && from == to {
+    return Some("./".to_string());
+  }
+
+  // workaround using parent directory until https://github.com/servo/rust-url/pull/754 is merged
+  let from = if !from.path().ends_with('/') {
+    if let Some(end_slash) = from.path().rfind('/') {
+      let mut new_from = from.clone();
+      new_from.set_path(&from.path()[..end_slash + 1]);
+      Cow::Owned(new_from)
+    } else {
+      Cow::Borrowed(from)
+    }
+  } else {
+    Cow::Borrowed(from)
+  };
+
+  // workaround for url crate not adding a trailing slash for a directory
+  // it seems to be fixed once a version greater than 2.2.2 is released
+  let mut text = from.make_relative(to)?;
+  if is_dir && !text.ends_with('/') && to.query().is_none() {
+    text.push('/');
+  }
+
+  Some(if text.starts_with("../") || text.starts_with("./") {
+    text
+  } else {
+    format!("./{}", text)
+  })
+}
+
+/// This function checks if input path has trailing slash or not. If input path
+/// has trailing slash it will return true else it will return false.
+pub fn path_has_trailing_slash(path: &Path) -> bool {
+  if let Some(path_str) = path.to_str() {
+    if cfg!(windows) {
+      path_str.ends_with('\\')
+    } else {
+      path_str.ends_with('/')
+    }
+  } else {
+    false
+  }
+}
+
+/// Gets a path with the specified file stem suffix.
+///
+/// Ex. `file.ts` with suffix `_2` returns `file_2.ts`
+pub fn path_with_stem_suffix(path: &Path, suffix: &str) -> PathBuf {
+  if let Some(file_name) = path.file_name().map(|f| f.to_string_lossy()) {
+    if let Some(file_stem) = path.file_stem().map(|f| f.to_string_lossy()) {
+      if let Some(ext) = path.extension().map(|f| f.to_string_lossy()) {
+        return if file_stem.to_lowercase().ends_with(".d") {
+          path.with_file_name(format!(
+            "{}{}.{}.{}",
+            &file_stem[..file_stem.len() - ".d".len()],
+            suffix,
+            // maintain casing
+            &file_stem[file_stem.len() - "d".len()..],
+            ext
+          ))
+        } else {
+          path.with_file_name(format!("{}{}.{}", file_stem, suffix, ext))
+        };
+      }
+    }
+
+    path.with_file_name(format!("{}{}", file_name, suffix))
+  } else {
+    path.with_file_name(suffix)
+  }
+}
+
+/// Gets if the provided character is not supported on all
+/// kinds of file systems.
+pub fn is_banned_path_char(c: char) -> bool {
+  matches!(c, '<' | '>' | ':' | '"' | '|' | '?' | '*')
+}
+
+/// Gets a safe local directory name for the provided url.
+///
+/// For example:
+/// https://deno.land:8080/path -> deno.land_8080/path
+pub fn root_url_to_safe_local_dirname(root: &ModuleSpecifier) -> PathBuf {
+  fn sanitize_segment(text: &str) -> String {
+    text
+      .chars()
+      .map(|c| if is_banned_segment_char(c) { '_' } else { c })
+      .collect()
+  }
+
+  fn is_banned_segment_char(c: char) -> bool {
+    matches!(c, '/' | '\\') || is_banned_path_char(c)
+  }
+
+  let mut result = String::new();
+  if let Some(domain) = root.domain() {
+    result.push_str(&sanitize_segment(domain));
+  }
+  if let Some(port) = root.port() {
+    if !result.is_empty() {
+      result.push('_');
+    }
+    result.push_str(&port.to_string());
+  }
+  let mut result = PathBuf::from(result);
+  if let Some(segments) = root.path_segments() {
+    for segment in segments.filter(|s| !s.is_empty()) {
+      result = result.join(sanitize_segment(segment));
+    }
+  }
+
+  result
+}
+
+#[cfg(test)]
+mod test {
+  use super::*;
+
+  #[test]
+  fn test_is_supported_ext() {
+    assert!(!is_supported_ext(Path::new("tests/subdir/redirects")));
+    assert!(!is_supported_ext(Path::new("README.md")));
+    assert!(is_supported_ext(Path::new("lib/typescript.d.ts")));
+    assert!(is_supported_ext(Path::new("testdata/run/001_hello.js")));
+    assert!(is_supported_ext(Path::new("testdata/run/002_hello.ts")));
+    assert!(is_supported_ext(Path::new("foo.jsx")));
+    assert!(is_supported_ext(Path::new("foo.tsx")));
+    assert!(is_supported_ext(Path::new("foo.TS")));
+    assert!(is_supported_ext(Path::new("foo.TSX")));
+    assert!(is_supported_ext(Path::new("foo.JS")));
+    assert!(is_supported_ext(Path::new("foo.JSX")));
+    assert!(is_supported_ext(Path::new("foo.mjs")));
+    assert!(is_supported_ext(Path::new("foo.mts")));
+    assert!(is_supported_ext(Path::new("foo.cjs")));
+    assert!(is_supported_ext(Path::new("foo.cts")));
+    assert!(!is_supported_ext(Path::new("foo.mjsx")));
+  }
+
+  #[test]
+  fn test_specifier_to_file_path() {
+    run_success_test("file:///", "/");
+    run_success_test("file:///test", "/test");
+    run_success_test("file:///dir/test/test.txt", "/dir/test/test.txt");
+    run_success_test(
+      "file:///dir/test%20test/test.txt",
+      "/dir/test test/test.txt",
+    );
+
+    fn run_success_test(specifier: &str, expected_path: &str) {
+      let result =
+        specifier_to_file_path(&ModuleSpecifier::parse(specifier).unwrap())
+          .unwrap();
+      assert_eq!(result, PathBuf::from(expected_path));
+    }
+  }
+
+  #[test]
+  fn test_ensure_directory_specifier() {
+    run_test("file:///", "file:///");
+    run_test("file:///test", "file:///test/");
+    run_test("file:///test/", "file:///test/");
+    run_test("file:///test/other", "file:///test/other/");
+    run_test("file:///test/other/", "file:///test/other/");
+
+    fn run_test(specifier: &str, expected: &str) {
+      let result =
+        ensure_directory_specifier(ModuleSpecifier::parse(specifier).unwrap());
+      assert_eq!(result.to_string(), expected);
+    }
+  }
+
+  #[test]
+  fn test_specifier_parent() {
+    run_test("file:///", "file:///");
+    run_test("file:///test", "file:///");
+    run_test("file:///test/", "file:///");
+    run_test("file:///test/other", "file:///test/");
+    run_test("file:///test/other.txt", "file:///test/");
+    run_test("file:///test/other/", "file:///test/");
+
+    fn run_test(specifier: &str, expected: &str) {
+      let result =
+        specifier_parent(&ModuleSpecifier::parse(specifier).unwrap());
+      assert_eq!(result.to_string(), expected);
+    }
+  }
+
+  #[test]
+  fn test_relative_specifier() {
+    let fixtures: Vec<(&str, &str, Option<&str>)> = vec![
+      ("file:///from", "file:///to", Some("./to")),
+      ("file:///from", "file:///from/other", Some("./from/other")),
+      ("file:///from", "file:///from/other/", Some("./from/other/")),
+      ("file:///from", "file:///other/from", Some("./other/from")),
+      ("file:///from/", "file:///other/from", Some("../other/from")),
+      ("file:///from", "file:///other/from/", Some("./other/from/")),
+      (
+        "file:///from",
+        "file:///to/other.txt",
+        Some("./to/other.txt"),
+      ),
+      (
+        "file:///from/test",
+        "file:///to/other.txt",
+        Some("../to/other.txt"),
+      ),
+      (
+        "file:///from/other.txt",
+        "file:///to/other.txt",
+        Some("../to/other.txt"),
+      ),
+      (
+        "https://deno.land/x/a/b/d.ts",
+        "https://deno.land/x/a/b/c.ts",
+        Some("./c.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/d.ts",
+        "https://deno.land/x/a/c.ts",
+        Some("../c.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/d.ts",
+        "https://deno.land/x/a/b/c/d.ts",
+        Some("./c/d.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/c/",
+        "https://deno.land/x/a/b/c/d.ts",
+        Some("./d.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/c/",
+        "https://deno.land/x/a/b/c/d/e.ts",
+        Some("./d/e.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/c/f.ts",
+        "https://deno.land/x/a/b/c/d/e.ts",
+        Some("./d/e.ts"),
+      ),
+      (
+        "https://deno.land/x/a/b/d.ts",
+        "https://deno.land/x/a/c.ts?foo=bar",
+        Some("../c.ts?foo=bar"),
+      ),
+      (
+        "https://deno.land/x/a/b/d.ts?foo=bar",
+        "https://deno.land/x/a/b/c.ts",
+        Some("./c.ts"),
+      ),
+      ("file:///a/b/d.ts", "file:///a/b/c.ts", Some("./c.ts")),
+      ("https://deno.land/x/a/b/c.ts", "file:///a/b/c.ts", None),
+      (
+        "https://deno.land/",
+        "https://deno.land/x/a/b/c.ts",
+        Some("./x/a/b/c.ts"),
+      ),
+      (
+        "https://deno.land/x/d/e/f.ts",
+        "https://deno.land/x/a/b/c.ts",
+        Some("../../a/b/c.ts"),
+      ),
+    ];
+    for (from_str, to_str, expected) in fixtures {
+      let from = ModuleSpecifier::parse(from_str).unwrap();
+      let to = ModuleSpecifier::parse(to_str).unwrap();
+      let actual = relative_specifier(&from, &to);
+      assert_eq!(
+        actual.as_deref(),
+        expected,
+        "from: \"{}\" to: \"{}\"",
+        from_str,
+        to_str
+      );
+    }
+  }
+
+  #[test]
+  fn test_path_has_trailing_slash() {
+    #[cfg(not(windows))]
+    {
+      run_test("/Users/johndoe/Desktop/deno-project/target/", true);
+      run_test(r"/Users/johndoe/deno-project/target//", true);
+      run_test("/Users/johndoe/Desktop/deno-project", false);
+      run_test(r"/Users/johndoe/deno-project\", false);
+    }
+
+    #[cfg(windows)]
+    {
+      run_test(r"C:\test\deno-project\", true);
+      run_test(r"C:\test\deno-project\\", true);
+      run_test(r"C:\test\file.txt", false);
+      run_test(r"C:\test\file.txt/", false);
+    }
+
+    fn run_test(path_str: &str, expected: bool) {
+      let path = Path::new(path_str);
+      let result = path_has_trailing_slash(path);
+      assert_eq!(result, expected);
+    }
+  }
+
+  #[test]
+  fn test_path_with_stem_suffix() {
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/"), "_2"),
+      PathBuf::from("/_2")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test"), "_2"),
+      PathBuf::from("/test_2")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test.txt"), "_2"),
+      PathBuf::from("/test_2.txt")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test/subdir"), "_2"),
+      PathBuf::from("/test/subdir_2")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test/subdir.other.txt"), "_2"),
+      PathBuf::from("/test/subdir.other_2.txt")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test.d.ts"), "_2"),
+      PathBuf::from("/test_2.d.ts")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test.D.TS"), "_2"),
+      PathBuf::from("/test_2.D.TS")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test.d.mts"), "_2"),
+      PathBuf::from("/test_2.d.mts")
+    );
+    assert_eq!(
+      path_with_stem_suffix(&PathBuf::from("/test.d.cts"), "_2"),
+      PathBuf::from("/test_2.d.cts")
+    );
+  }
+}
diff --git a/cli/util/progress_bar.rs b/cli/util/progress_bar.rs
new file mode 100644
index 000000000..5b49fb279
--- /dev/null
+++ b/cli/util/progress_bar.rs
@@ -0,0 +1,143 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use crate::colors;
+use deno_core::parking_lot::Mutex;
+use indexmap::IndexSet;
+use std::sync::Arc;
+use std::time::Duration;
+
+#[derive(Clone, Debug, Default)]
+pub struct ProgressBar(Arc<Mutex<ProgressBarInner>>);
+
+#[derive(Debug)]
+struct ProgressBarInner {
+  pb: Option<indicatif::ProgressBar>,
+  is_tty: bool,
+  in_flight: IndexSet<String>,
+}
+
+impl Default for ProgressBarInner {
+  fn default() -> Self {
+    Self {
+      pb: None,
+      is_tty: colors::is_tty(),
+      in_flight: IndexSet::default(),
+    }
+  }
+}
+
+impl ProgressBarInner {
+  fn get_or_create_pb(&mut self) -> indicatif::ProgressBar {
+    if let Some(pb) = self.pb.as_ref() {
+      return pb.clone();
+    }
+
+    let pb = indicatif::ProgressBar::new_spinner();
+    pb.enable_steady_tick(Duration::from_millis(120));
+    pb.set_prefix("Download");
+    pb.set_style(
+      indicatif::ProgressStyle::with_template(
+        "{prefix:.green} {spinner:.green} {msg}",
+      )
+      .unwrap()
+      .tick_strings(&["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"]),
+    );
+    self.pb = Some(pb);
+    self.pb.as_ref().unwrap().clone()
+  }
+
+  fn add_in_flight(&mut self, msg: &str) {
+    if self.in_flight.contains(msg) {
+      return;
+    }
+
+    self.in_flight.insert(msg.to_string());
+  }
+
+  /// Returns if removed "in-flight" was last entry and progress
+  /// bar needs to be updated.
+  fn remove_in_flight(&mut self, msg: &str) -> bool {
+    if !self.in_flight.contains(msg) {
+      return false;
+    }
+
+    let mut is_last = false;
+    if let Some(last) = self.in_flight.last() {
+      is_last = last == msg;
+    }
+    self.in_flight.remove(msg);
+    is_last
+  }
+
+  fn update_progress_bar(&mut self) {
+    let pb = self.get_or_create_pb();
+    if let Some(msg) = self.in_flight.last() {
+      pb.set_message(msg.clone());
+    }
+  }
+}
+
+pub struct UpdateGuard {
+  pb: ProgressBar,
+  msg: String,
+  noop: bool,
+}
+
+impl Drop for UpdateGuard {
+  fn drop(&mut self) {
+    if self.noop {
+      return;
+    }
+
+    let mut inner = self.pb.0.lock();
+    if inner.remove_in_flight(&self.msg) {
+      inner.update_progress_bar();
+    }
+  }
+}
+
+impl ProgressBar {
+  pub fn update(&self, msg: &str) -> UpdateGuard {
+    let mut guard = UpdateGuard {
+      pb: self.clone(),
+      msg: msg.to_string(),
+      noop: false,
+    };
+    let mut inner = self.0.lock();
+
+    // If we're not running in TTY we're just gonna fallback
+    // to using logger crate.
+    if !inner.is_tty {
+      log::log!(log::Level::Info, "{} {}", colors::green("Download"), msg);
+      guard.noop = true;
+      return guard;
+    }
+
+    inner.add_in_flight(msg);
+    inner.update_progress_bar();
+    guard
+  }
+
+  pub fn clear(&self) {
+    let mut inner = self.0.lock();
+
+    if let Some(pb) = inner.pb.as_ref() {
+      pb.finish_and_clear();
+      inner.pb = None;
+    }
+  }
+
+  pub fn clear_guard(&self) -> ClearGuard {
+    ClearGuard { pb: self.clone() }
+  }
+}
+
+pub struct ClearGuard {
+  pb: ProgressBar,
+}
+
+impl Drop for ClearGuard {
+  fn drop(&mut self) {
+    self.pb.clear();
+  }
+}
diff --git a/cli/util/text_encoding.rs b/cli/util/text_encoding.rs
new file mode 100644
index 000000000..c16a1289d
--- /dev/null
+++ b/cli/util/text_encoding.rs
@@ -0,0 +1,162 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+use encoding_rs::*;
+use std::borrow::Cow;
+use std::io::Error;
+use std::io::ErrorKind;
+
+pub const BOM_CHAR: char = '\u{FEFF}';
+
+/// Attempts to detect the character encoding of the provided bytes.
+///
+/// Supports UTF-8, UTF-16 Little Endian and UTF-16 Big Endian.
+pub fn detect_charset(bytes: &'_ [u8]) -> &'static str {
+  const UTF16_LE_BOM: &[u8] = b"\xFF\xFE";
+  const UTF16_BE_BOM: &[u8] = b"\xFE\xFF";
+
+  if bytes.starts_with(UTF16_LE_BOM) {
+    "utf-16le"
+  } else if bytes.starts_with(UTF16_BE_BOM) {
+    "utf-16be"
+  } else {
+    // Assume everything else is utf-8
+    "utf-8"
+  }
+}
+
+/// Attempts to convert the provided bytes to a UTF-8 string.
+///
+/// Supports all encodings supported by the encoding_rs crate, which includes
+/// all encodings specified in the WHATWG Encoding Standard, and only those
+/// encodings (see: <https://encoding.spec.whatwg.org/>).
+pub fn convert_to_utf8<'a>(
+  bytes: &'a [u8],
+  charset: &'_ str,
+) -> Result<Cow<'a, str>, Error> {
+  match Encoding::for_label(charset.as_bytes()) {
+    Some(encoding) => encoding
+      .decode_without_bom_handling_and_without_replacement(bytes)
+      .ok_or_else(|| ErrorKind::InvalidData.into()),
+    None => Err(Error::new(
+      ErrorKind::InvalidInput,
+      format!("Unsupported charset: {}", charset),
+    )),
+  }
+}
+
+/// Strips the byte order mark from the provided text if it exists.
+pub fn strip_bom(text: &str) -> &str {
+  if text.starts_with(BOM_CHAR) {
+    &text[BOM_CHAR.len_utf8()..]
+  } else {
+    text
+  }
+}
+
+static SOURCE_MAP_PREFIX: &str =
+  "//# sourceMappingURL=data:application/json;base64,";
+
+pub fn source_map_from_code(code: &str) -> Option<Vec<u8>> {
+  let last_line = code.rsplit(|u| u == '\n').next()?;
+  if last_line.starts_with(SOURCE_MAP_PREFIX) {
+    let input = last_line.split_at(SOURCE_MAP_PREFIX.len()).1;
+    let decoded_map = base64::decode(input)
+      .expect("Unable to decode source map from emitted file.");
+    Some(decoded_map)
+  } else {
+    None
+  }
+}
+
+pub fn code_without_source_map(mut code: String) -> String {
+  if let Some(last_line_index) = code.rfind('\n') {
+    if code[last_line_index + 1..].starts_with(SOURCE_MAP_PREFIX) {
+      code.truncate(last_line_index + 1);
+      code
+    } else {
+      code
+    }
+  } else {
+    code
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  fn test_detection(test_data: &[u8], expected_charset: &str) {
+    let detected_charset = detect_charset(test_data);
+    assert_eq!(
+      expected_charset.to_lowercase(),
+      detected_charset.to_lowercase()
+    );
+  }
+
+  #[test]
+  fn test_detection_utf8_no_bom() {
+    let test_data = "Hello UTF-8 it is \u{23F0} for Deno!"
+      .to_owned()
+      .into_bytes();
+    test_detection(&test_data, "utf-8");
+  }
+
+  #[test]
+  fn test_detection_utf16_little_endian() {
+    let test_data = b"\xFF\xFEHello UTF-16LE".to_owned().to_vec();
+    test_detection(&test_data, "utf-16le");
+  }
+
+  #[test]
+  fn test_detection_utf16_big_endian() {
+    let test_data = b"\xFE\xFFHello UTF-16BE".to_owned().to_vec();
+    test_detection(&test_data, "utf-16be");
+  }
+
+  #[test]
+  fn test_decoding_unsupported_charset() {
+    let test_data = Vec::new();
+    let result = convert_to_utf8(&test_data, "utf-32le");
+    assert!(result.is_err());
+    let err = result.expect_err("Err expected");
+    assert!(err.kind() == ErrorKind::InvalidInput);
+  }
+
+  #[test]
+  fn test_decoding_invalid_utf8() {
+    let test_data = b"\xFE\xFE\xFF\xFF".to_vec();
+    let result = convert_to_utf8(&test_data, "utf-8");
+    assert!(result.is_err());
+    let err = result.expect_err("Err expected");
+    assert!(err.kind() == ErrorKind::InvalidData);
+  }
+
+  #[test]
+  fn test_source_without_source_map() {
+    run_test("", "");
+    run_test("\n", "\n");
+    run_test("\r\n", "\r\n");
+    run_test("a", "a");
+    run_test("a\n", "a\n");
+    run_test("a\r\n", "a\r\n");
+    run_test("a\r\nb", "a\r\nb");
+    run_test("a\nb\n", "a\nb\n");
+    run_test("a\r\nb\r\n", "a\r\nb\r\n");
+    run_test(
+      "test\n//# sourceMappingURL=data:application/json;base64,test",
+      "test\n",
+    );
+    run_test(
+      "test\r\n//# sourceMappingURL=data:application/json;base64,test",
+      "test\r\n",
+    );
+    run_test(
+      "\n//# sourceMappingURL=data:application/json;base64,test",
+      "\n",
+    );
+
+    fn run_test(input: &str, output: &str) {
+      assert_eq!(code_without_source_map(input.to_string()), output);
+    }
+  }
+}
diff --git a/cli/util/unix.rs b/cli/util/unix.rs
new file mode 100644
index 000000000..f282f6cfe
--- /dev/null
+++ b/cli/util/unix.rs
@@ -0,0 +1,45 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+/// Raise soft file descriptor limit to hard file descriptor limit.
+/// This is the difference between `ulimit -n` and `ulimit -n -H`.
+pub fn raise_fd_limit() {
+  #[cfg(unix)]
+  // TODO(bartlomieju):
+  #[allow(clippy::undocumented_unsafe_blocks)]
+  unsafe {
+    let mut limits = libc::rlimit {
+      rlim_cur: 0,
+      rlim_max: 0,
+    };
+
+    if 0 != libc::getrlimit(libc::RLIMIT_NOFILE, &mut limits) {
+      return;
+    }
+
+    if limits.rlim_cur == libc::RLIM_INFINITY {
+      return;
+    }
+
+    // No hard limit? Do a binary search for the effective soft limit.
+    if limits.rlim_max == libc::RLIM_INFINITY {
+      let mut min = limits.rlim_cur;
+      let mut max = 1 << 20;
+
+      while min + 1 < max {
+        limits.rlim_cur = min + (max - min) / 2;
+        match libc::setrlimit(libc::RLIMIT_NOFILE, &limits) {
+          0 => min = limits.rlim_cur,
+          _ => max = limits.rlim_cur,
+        }
+      }
+
+      return;
+    }
+
+    // Raise the soft limit to the hard limit.
+    if limits.rlim_cur < limits.rlim_max {
+      limits.rlim_cur = limits.rlim_max;
+      libc::setrlimit(libc::RLIMIT_NOFILE, &limits);
+    }
+  }
+}
diff --git a/cli/util/windows.rs b/cli/util/windows.rs
new file mode 100644
index 000000000..0801ff2f5
--- /dev/null
+++ b/cli/util/windows.rs
@@ -0,0 +1,90 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+
+/// Ensures that stdin, stdout, and stderr are open and have valid HANDLEs
+/// associated with them. There are many places where a `std::fs::File` is
+/// constructed from a stdio handle; if the handle is null this causes a panic.
+pub fn ensure_stdio_open() {
+  #[cfg(windows)]
+  // SAFETY: winapi calls
+  unsafe {
+    use std::mem::size_of;
+    use winapi::shared::minwindef::DWORD;
+    use winapi::shared::minwindef::FALSE;
+    use winapi::shared::minwindef::TRUE;
+    use winapi::shared::ntdef::NULL;
+    use winapi::shared::winerror::ERROR_INVALID_HANDLE;
+    use winapi::um::errhandlingapi::GetLastError;
+    use winapi::um::fileapi::CreateFileA;
+    use winapi::um::fileapi::OPEN_EXISTING;
+    use winapi::um::handleapi::GetHandleInformation;
+    use winapi::um::handleapi::INVALID_HANDLE_VALUE;
+    use winapi::um::minwinbase::SECURITY_ATTRIBUTES;
+    use winapi::um::processenv::GetStdHandle;
+    use winapi::um::processenv::SetStdHandle;
+    use winapi::um::winbase::STD_ERROR_HANDLE;
+    use winapi::um::winbase::STD_INPUT_HANDLE;
+    use winapi::um::winbase::STD_OUTPUT_HANDLE;
+    use winapi::um::winnt::FILE_ATTRIBUTE_NORMAL;
+    use winapi::um::winnt::FILE_GENERIC_READ;
+    use winapi::um::winnt::FILE_GENERIC_WRITE;
+    use winapi::um::winnt::FILE_READ_ATTRIBUTES;
+    use winapi::um::winnt::FILE_SHARE_READ;
+    use winapi::um::winnt::FILE_SHARE_WRITE;
+
+    for std_handle in [STD_INPUT_HANDLE, STD_OUTPUT_HANDLE, STD_ERROR_HANDLE] {
+      // Check whether stdio handle is open.
+      let is_valid = match GetStdHandle(std_handle) {
+        NULL | INVALID_HANDLE_VALUE => false,
+        handle => {
+          // The stdio handle is open; check whether its handle is valid.
+          let mut flags: DWORD = 0;
+          match GetHandleInformation(handle, &mut flags) {
+            TRUE => true,
+            FALSE if GetLastError() == ERROR_INVALID_HANDLE => false,
+            FALSE => {
+              panic!("GetHandleInformation failed (error {})", GetLastError());
+            }
+            _ => unreachable!(),
+          }
+        }
+      };
+
+      if !is_valid {
+        // Open NUL device.
+        let desired_access = match std_handle {
+          STD_INPUT_HANDLE => FILE_GENERIC_READ,
+          _ => FILE_GENERIC_WRITE | FILE_READ_ATTRIBUTES,
+        };
+        let security_attributes = SECURITY_ATTRIBUTES {
+          nLength: size_of::<SECURITY_ATTRIBUTES>() as DWORD,
+          lpSecurityDescriptor: NULL,
+          bInheritHandle: TRUE,
+        };
+        let file_handle = CreateFileA(
+          b"\\\\?\\NUL\0" as *const _ as *mut _,
+          desired_access,
+          FILE_SHARE_READ | FILE_SHARE_WRITE,
+          &security_attributes as *const _ as *mut _,
+          OPEN_EXISTING,
+          FILE_ATTRIBUTE_NORMAL,
+          NULL,
+        );
+        match file_handle {
+          NULL => unreachable!(),
+          INVALID_HANDLE_VALUE => {
+            panic!("Could not open NUL device (error {})", GetLastError());
+          }
+          _ => {}
+        }
+
+        // Assign the opened NUL handle to the missing stdio handle.
+        let success = SetStdHandle(std_handle, file_handle);
+        match success {
+          TRUE => {}
+          FALSE => panic!("SetStdHandle failed (error {})", GetLastError()),
+          _ => unreachable!(),
+        }
+      }
+    }
+  }
+}