# `mix schooner.check`
[🔗](https://github.com/ausimian/schooner/blob/1.2.0/lib/mix/tasks/schooner.check.ex#L1)

Checks Scheme scripts for problems without running them, with
`Schooner.check/3`.

    $ mix schooner.check "scripts/**/*.scm" --env MyApp.Scripts.environment
    scripts/discounts.scm:1:9: error[unknown_library]: library not found: (myapp promos)
    scripts/draft.scm:1:27: error[unbound]: unbound variable: unit-prise
    2 errors in 2 files

Each argument is a file, a directory (every `.scm` file under it) or a
glob. Quote globs so the task expands them rather than the shell.
The task fails when an argument matches no files.

## Options

  * `--env Mod.fun` — check against the `Schooner.Environment`
    returned by the zero-arity function `Mod.fun`. Without it, the
    environment is the one configured with

        config :schooner, :tooling_environment, {Mod, :fun, args}

    and without that, every standard library, all imported: the
    surface `Schooner.run/1` gives a script that imports nothing.
    Prefer your application's real environment, which is usually
    much narrower.
  * `--format text|json` — `text` (the default) prints one line per
    diagnostic, `file:line:col: severity[code]: message`, and a
    summary. `json` prints one JSON object:

        {"diagnostics": [{"file": "scripts/draft.scm", "line": 1, "column": 27,
                          "severity": "error", "code": "unbound",
                          "message": "unbound variable: unit-prise"}],
         "errors": 1, "warnings": 0, "files": 2}

    `files` counts the files checked. `line` and `column` are `null`
    when the position is unknown. The task keeps compiler progress
    out of the JSON, but Mix may compile dependencies before the
    task starts, so run `mix compile` first when another program
    reads the output.
  * `--warnings-as-errors` — fail when there are warnings, too.

The task exits with status 1 when it finds an error, and 0
otherwise.

---

*Consult [api-reference.md](api-reference.md) for complete listing*