Fourteen criteria (eleven mandatory), each tagged with an ISO/IEC 25010 characteristic: strict mode, quoting, naming, shellcheck, error handling, temporary files, secrets, safe defaults, header, traceability and tests. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
3.6 KiB
3.6 KiB
Quality Criteria: Shell Script (bash)
Metadata
| Key | Value |
|---|---|
| ID | QC-SH-001 |
| CrossReference | QC-DCD-001, QC-ADR-001 |
Version History
| Date | Status | Author | Reviewer | Change | Commit |
|---|---|---|---|---|---|
| 2026-10-02 | Accepted | Jens Tirsvad Nielsen | S07 | Initial version | — |
Purpose
Shell scripts automate steps that change files, repositories and remote systems, so a defect often does damage quietly. This checklist confirms that a bash script follows the shell conventions (strict mode, quoting, error handling, safe defaults), so that it is predictable, maintainable and safe to run.
Quality Criteria Checklist
Level: Mandatory criteria are the baseline every instance must meet; Optional criteria are advanced and may be deferred.
| # | Criterion | Level | ISO/IEC 25010 Characteristic(s) | Notes |
|---|---|---|---|---|
| 1 | Starts with #!/usr/bin/env bash and set -euo pipefail (or a comment explains the exception) |
Mandatory | Reliability | |
| 2 | Every expansion is quoted; lists are arrays; tests use [[ ]] and $(...) |
Mandatory | Reliability, Security | Unquoted expansions break on spaces and globs |
| 3 | Names follow the conventions: kebab-case.sh files, snake_case functions and variables, UPPER_SNAKE constants and environment variables |
Mandatory | Maintainability, Usability | |
| 4 | Passes shellcheck and bash -n with no unexplained disable comments |
Mandatory | Maintainability, Reliability | State the tool versions used |
| 5 | Errors go to standard error with an error: message and a non-zero exit code; bad or missing arguments print a usage line |
Mandatory | Reliability, Usability | |
| 6 | Temporary files use mktemp with a trap ... EXIT cleanup; no fixed /tmp names |
Mandatory | Security, Reliability | |
| 7 | No secret is written in the script, echoed, or put on a command line; secrets come from the environment or a gitignored file | Mandatory | Security | |
| 8 | A script that changes state outside its own directory defaults to a dry run or needs an explicit flag, and says so in its header | Mandatory | Reliability, Security | |
| 9 | A header comment states purpose, usage, options, environment variables and exit codes | Mandatory | Usability, Maintainability | |
| 10 | The script implements a task or design it cites; deviations are recorded | Mandatory | Functional Suitability, Maintainability | |
| 11 | Behaviour is tested for success, failure and any disabled or bypass path | Mandatory | Reliability | Tests may be a recorded manual run |
| 12 | Formatted with shfmt (or the project's formatter) |
Optional | Maintainability | |
| 13 | Safe to re-run: a second run does not duplicate or corrupt what the first did | Optional | Reliability | |
| 14 | Bash version and external tools it needs are stated; GNU-only options are named | Optional | Portability |
Common Defects
- Unquoted
$varthat breaks on a space or an empty value - Missing
set -euo pipefail, or|| truehiding a real failure - Parsing
lsoutput instead of using globs orfind -print0 - A script that deletes or overwrites by default with no dry run
- A token echoed to the terminal or kept in the script
- No usage message, so a wrong call fails with a cryptic error
- A script that implements nothing in any task or design
Traceability Rule
- Backward: Design Class Diagram checklist (QC-DCD-001) where the script implements a design; Architecture Decision Record checklist (QC-ADR-001) for the decisions that constrain it
- Forward: none, source code is the end of the QC checklist chain