fix(flags): don't treat empty run command as task subcommand (#25708)

cli/args/flags.rs

@@ -4679,7 +4679,7 @@ fn repl_parse(
 fn run_parse(
   flags: &mut Flags,
   matches: &mut ArgMatches,
-  app: Command,
+  mut app: Command,
   bare: bool,
 ) -> clap::error::Result<()> {
   runtime_args_parse(flags, matches, true, true)?;
@@ -4701,11 +4701,16 @@ fn run_parse(
       "[SCRIPT_ARG] may only be omitted with --v8-flags=--help, else to use the repl with arguments, please use the `deno repl` subcommand",
     ));
   } else {
-    flags.subcommand = DenoSubcommand::Task(TaskFlags {
-      cwd: None,
-      task: None,
-      is_run: true,
-    });
+    return Err(
+      app
+        .get_subcommands_mut()
+        .find(|subcommand| subcommand.get_name() == "run")
+        .unwrap()
+        .error(
+          clap::error::ErrorKind::MissingRequiredArgument,
+          "[SCRIPT_ARG] may only be omitted with --v8-flags=--help",
+        ),
+    );
   }
 
   Ok(())
@@ -5927,7 +5932,7 @@ mod tests {
     );
 
     let r = flags_from_vec(svec!["deno", "run", "--v8-flags=--expose-gc"]);
-    assert!(r.is_ok());
+    assert!(r.is_err());
   }
 
   #[test]

cli/tools/task.rs

@@ -36,19 +36,7 @@ pub async fn execute_script(
   let cli_options = factory.cli_options()?;
   let start_dir = &cli_options.start_dir;
   if !start_dir.has_deno_or_pkg_json() {
-    if task_flags.is_run {
-      bail!(
-        r#"deno run couldn't find deno.json(c).
-If you meant to run a script, specify it, e.g., `deno run ./script.ts`.
-To run a task, ensure the config file exists.
-Examples:
-- Script: `deno run ./script.ts`
-- Task: `deno run dev`
-See https://docs.deno.com/go/config"#
-      )
-    } else {
-      bail!("deno task couldn't find deno.json(c). See https://docs.deno.com/go/config")
-    }
+    bail!("deno task couldn't find deno.json(c). See https://docs.deno.com/go/config")
   }
   let force_use_pkg_json =
     std::env::var_os(crate::task_runner::USE_PKG_JSON_HIDDEN_ENV_VAR_NAME)

tests/specs/run/run_task/__test__.jsonc

@@ -1,5 +1,10 @@
 {
   "tests": {
+    "deno_run_empty": {
+      "args": "run",
+      "output": "empty.out",
+      "exitCode": 1
+    },
     "deno_run_task": {
       "args": "run main",
       "output": "main.out"

tests/specs/run/run_task/empty.out

@@ -0,0 +1,4 @@
+error: [SCRIPT_ARG] may only be omitted with --v8-flags=--help
+
+Usage: deno run [OPTIONS] [SCRIPT_ARG]...
+