validate

validate(paths: string[], opts?: ValidateOptions, deps?: ReadsFile): ValidateResult parses each .feature file and returns a result reporting whether each is well-formed Gherkin. Per file it carries ok plus an errors list of {line, message, code}; the result carries a summary {files, errors}. It is pure: it returns a value and never exits. The exit-code gate (1 on any error) is a CLI concern layered on top — the engine does not gate.

import { validate } from 'gherkin-cli'

const result = validate(['features/login.feature', 'features/checkout.feature'])
if (result.summary.errors > 0) {
  for (const file of result.files.filter((f) => !f.ok)) {
    for (const err of file.errors) {
      console.error(`${file.file}:${err.line} ${err.code} ${err.message}`)
    }
  }
}

Parameters

Param	Type	Description
paths	string[]	The .feature files to validate.
deps.readFile	ReadsFile	Injected filesystem seam (separate 3rd arg, default nodeReadsFile) — pass a fake to test without disk.

Behavior

• Per file: ok plus an errors list of {line, message, code} — code is EPARSE for a syntax error, ENOENT for a missing file.
• A missing file is reported as not ok with an ENOENT error entry — the engine does not throw.
• A clean run reports every file ok and summary.errors === 0 — a return value, not an exit code.
• The engine never exits or gates; the CLI maps any error to exit 1.
• The result carries a pre-computed summary {files, errors}.
• The filesystem seam is a separate 3rd deps argument — a ReadsFile role interface (default nodeReadsFile), not an option — so you can validate in-memory text with no disk access: validate(paths, {}, { readFile: (path) => fixtures[path] }).

See also

• validate — the same check as a command with a gating exit code.
• parse — project a suite into a compact digest.
• diff — classify scenario changes against a git base.