feat(unstable): deno run --watch (#7382)

Co-authored-by: Sebastian Seedorf <mail@sebse.de>

1 files changed, 37 insertions, 0 deletions

diff --git a/cli/flags.rs b/cli/flags.rs
index 443411bc3..18fd3b29e 100644
--- a/cli/flags.rs
+++ b/cli/flags.rs
@@ -123,6 +123,7 @@ pub struct Flags {
   pub unstable: bool,
   pub v8_flags: Option<Vec<String>>,
   pub version: bool,
+  pub watch: bool,
   pub write_allowlist: Vec<PathBuf>,
 }
 
@@ -562,6 +563,7 @@ fn run_parse(flags: &mut Flags, matches: &clap::ArgMatches) {
     flags.argv.push(v);
   }
 
+  flags.watch = matches.is_present("watch");
   flags.subcommand = DenoSubcommand::Run { script };
 }
 
@@ -1157,6 +1159,7 @@ fn run_test_args<'a, 'b>(app: App<'a, 'b>) -> App<'a, 'b> {
 
 fn run_subcommand<'a, 'b>() -> App<'a, 'b> {
   run_test_args(SubCommand::with_name("run"))
+    .arg(watch_arg())
     .setting(AppSettings::TrailingVarArg)
     .arg(script_arg())
     .about("Run a program given a filename or url to the module. Use '-' as a filename to read from stdin.")
@@ -1409,6 +1412,17 @@ fn v8_flags_arg_parse(flags: &mut Flags, matches: &ArgMatches) {
   }
 }
 
+fn watch_arg<'a, 'b>() -> Arg<'a, 'b> {
+  Arg::with_name("watch")
+    .requires("unstable")
+    .long("watch")
+    .help("Watch for file changes and restart process automatically")
+    .long_help(
+      "Watch for file changes and restart process automatically.
+Only local files from entry point module graph are watched.",
+    )
+}
+
 fn no_check_arg<'a, 'b>() -> Arg<'a, 'b> {
   Arg::with_name("no-check")
     .long("no-check")
@@ -1561,6 +1575,29 @@ mod tests {
   }
 
   #[test]
+  fn run_watch() {
+    let r = flags_from_vec_safe(svec![
+      "deno",
+      "run",
+      "--unstable",
+      "--watch",
+      "script.ts"
+    ]);
+    let flags = r.unwrap();
+    assert_eq!(
+      flags,
+      Flags {
+        subcommand: DenoSubcommand::Run {
+          script: "script.ts".to_string(),
+        },
+        watch: true,
+        unstable: true,
+        ..Flags::default()
+      }
+    );
+  }
+
+  #[test]
   fn run_reload_allow_write() {
     let r = flags_from_vec_safe(svec![
       "deno",