3. Parse feature files with Cucumber's Gherkin parser

Date: 2026-08-29

Status

Accepted

Context

scenari parsed feature files with its own instaparse grammar. Every Gherkin construct it did not know -- Rule, Background, tags on Examples, several Examples blocks, ~70 languages, doc string content types -- had to be added by hand, and a file Cucumber accepts could be rejected or misread.

Decision

Parse feature files with io.cucumber/gherkin, the reference implementation, and build the feature map from its pickles.

Consequences

• Clornichon reads what Cucumber reads, and follows the language as Cucumber evolves it.
• Parse errors come with line and column.
• Stricter: a file must start with Feature: (or a tag or comment), a non-English file needs a # language: header.
• A Java dependency, and the parser's messages (Envelope) are the base of a future cucumber-messages report.