| --- |
| license: mit |
| task_categories: |
| - text-generation |
| language: |
| - en |
| tags: |
| - shell |
| - command-correction |
| - benchmark |
| - terminal |
| pretty_name: "mash-bench" |
| size_categories: |
| - n<1K |
| --- |
| |
| # mash-bench |
|
|
| 203 real-world shell-command **repair** scenarios for evaluating command |
| correction models — as of Aug 2026, the first benchmark for this task. Each |
| scenario is a wrong/garbled command as a human actually typed it, the stderr it |
| produced (187/203 have it), and one or more acceptable corrections. |
|
|
| ```json |
| {"input": "cd..", "stderr": "-bash: cd..: command not found", "expected": ["cd .."], "source": "nofaq"} |
| {"input": "git brnch", "stderr": "git: 'brnch' is not a git command. See 'git --help'.", "expected": ["git branch"], "source": "thefuck"} |
| ``` |
|
|
| ## Sources |
|
|
| - **nofaq** (139 scenarios) — the artifact of *NoFAQ: Synthesizing Command |
| Repairs from Examples* (D'Antoni, Singh, Vaughn; ESEC/FSE 2017), |
| [MichaelBVaughn/NoFAQ](https://github.com/MichaelBVaughn/NoFAQ), MIT. |
| Extracted from `Synthesis/RuleRepair/TestExamples.fs`. |
| - **thefuck** (64 scenarios) — inputs, stderr, and fixes taken verbatim from |
| the rule *test files* of [nvbn/thefuck](https://github.com/nvbn/thefuck) |
| (MIT), spanning git typos, missing sudo, cd errors, package managers, and |
| more. |
|
|
| Scenarios were deduped across sources; entries with fabricated-looking or |
| machine-state-dependent fixes were dropped; alternate corrections were added |
| only where genuinely equivalent. Full cleaning log in `PROVENANCE.md`. |
|
|
| ## Scoring |
|
|
| Two modes matter: |
|
|
| - **bare input** — the model sees only the typed command. Fair for typo-class |
| scenarios (most of `thefuck`). |
| - **with stderr** — the error text is appended to the input. Required for |
| repair-class scenarios (most of `nofaq`), whose fixes depend on the error |
| (`cd files` → `mkdir files; cd files` only given "no such file or |
| directory"). |
|
|
| Report both, per source. Exact match against any entry in `expected` |
| (whitespace-normalized) is the metric; it is conservative — functionally |
| equivalent alternative fixes count as misses unless listed. |
|
|
| Runner: [`training/bench.py`](https://github.com/lumpenspace/fash/blob/main/training/bench.py) |
| in the fash repo. |
|
|
