denoland/deno · error · AnyError

the following required arguments were not provided: <file_

Error message

the following required arguments were not provided:
  <file_path>

What it means

After the argument loop, dcore requires at least one positional file_path. If every token was an option (or no arguments were given at all), file_path is None and the parser bails listing the missing required `<file_path>`. `-h`/`--help` is the deliberate exception: it prints usage and exits successfully.

Source

Thrown at libs/dcore/src/main.rs:233

          let Some(value) = value else {
            bail!("equal sign is needed when assigning values to '--v8-flags'");
          };
          out.v8_flags.extend(value.split(',').map(String::from));
        }
        _ if name.starts_with('-') && name != "-" => {
          bail!("unexpected argument '{name}' found");
        }
        _ => {
          if file_path.is_some() {
            bail!("unexpected argument '{arg}' found");
          }
          file_path = Some(arg);
        }
      }
    }

    let Some(file_path) = file_path else {
      bail!(
        "the following required arguments were not provided:\n  <file_path>"
      );
    };
    out.file_path = file_path;
    Ok(Some(out))
  }

  fn inspect(&self) -> Option<(SocketAddr, InspectMode)> {
    let default = || "127.0.0.1:9229".parse::<SocketAddr>().unwrap();
    if let Some(addr) = self.inspect {
      return Some((addr.unwrap_or_else(default), InspectMode::Immediate));
    }
    if let Some(addr) = self.inspect_wait {
      return Some((
        addr.unwrap_or_else(default),
        InspectMode::WaitForConnection,
      ));
    }

View on GitHub (pinned to 9ad36f7a2c)

Solutions

Add the entry script: `dcore --strace-ops app.js`.
In templates/wrappers, guard so the file argument is never empty before invoking dcore.
Use `dcore -h` when you only want usage — it does not raise this error.

Example fix

# before
dcore --strace-ops
# error: the following required arguments were not provided:
#   <file_path>

# after
dcore --strace-ops app.js

Defensive patterns

Strategy: validation

Validate before calling

# require a positional file before invoking dcore
has_file=0
for a in "$@"; do case "$a" in -*) ;; *) has_file=1;; esac; done
[ "$has_file" -eq 0 ] && { echo "dcore requires <file_path>"; exit 2; }

Prevention

Fail fast in CI templates when the entry-file variable is empty.
Use `dcore -h` for usage checks — it exits cleanly without a file.
Keep a canonical example command with the file argument in runbook docs.

When it happens

Trigger: `dcore --strace-ops` with no file; `dcore` invoked bare; `dcore --inspect` with no file; any invocation where all arguments were consumed as options.

Common situations: Smoke-testing a flag without providing a script; CI commands assembled from templated variables where the file-path variable expands to empty; copy-paste from examples that omitted the entry file.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of denoland/deno@9ad36f7a2c (2026-08-20). Data as JSON: /api/errors/6893d9a46acc8014. Report an issue: GitHub.