file_shebang

CategoriesContent Unix metadata

First line of each file in scope must match the shebang regex. Pairs with executable_has_shebang (which checks shebang presence on +x files) — file_shebang checks shebang shape.

Default shebang: is ^#!, which only enforces presence; almost every useful config supplies a tighter regex pinning the interpreter.

Options

Option	Type	Required	Default	Description
`shebang`	string		`^#!`	Rust regex; the first line of every matched file must match. Default `^#!` only enforces shebang presence.

Plus the common paths, level, id, and when fields. This table is generated from the JSON Schema; option types and defaults are authoritative.

Example

Scripts without the required shebang

The rule fires on this repository:

scripts/
scripts/hardcoded.sh
scripts/missing.sh
scripts/ok.sh

#!/bin/bash
echo legacy

echo no shebang

#!/usr/bin/env bash
echo ok

With this .alint.yml:

version: 1
rules:
  - id: scripts-use-env-bash
    kind: file_shebang
    paths: "scripts/*.sh"
    shebang: '^#!/usr/bin/env bash$'
    level: error

alint check reports:

--- scripts/hardcoded.sh -------------------------------------------------------
  x  error    scripts-use-env-bash
              1:1  first line "#!/bin/bash" does not match required shebang
              /^#!/usr/bin/env bash$/

--- scripts/missing.sh ---------------------------------------------------------
  x  error    scripts-use-env-bash
              1:1  first line "echo no shebang" does not match required shebang
              /^#!/usr/bin/env bash$/

Summary (2 violations):
  x 2 errors
  0 passing * 1 failing

Every script uses the env-style shebang

This repository is compliant:

scripts/
scripts/build.sh
scripts/ci.sh

#!/usr/bin/env bash
set -euo pipefail
echo ok

#!/usr/bin/env bash
echo ok

With this .alint.yml:

version: 1
rules:
  - id: scripts-use-env-bash
    kind: file_shebang
    paths: "scripts/*.sh"
    shebang: '^#!/usr/bin/env bash$'
    level: error

alint check reports:

v All 1 rule(s) passed.