CoercionMode

type CoercionMode = "off" | "warn" | "fix";

Defined in: packages/core/src/coercion.ts:27

YAML 1.1 coercion-trap predicate (#137).

Actio parses .actio.yml with the YAML 1.2 core schema, so author tokens like no, on, 1:30, 2024-01-01, 1_000 survive parsing as JS strings, and the emitter writes them back unquoted. A downstream YAML 1.1 consumer then re-reads those plain tokens with the older schema and coerces them (no→false, 1:30→90, 2024-01-01→a date, 1_000→1000). This predicate flags exactly the strings a 1.1 consumer would mis-type so the emitter can defensively quote them.

Scope, honestly: the GitHub Actions workflow parser largely preserves these as strings in string positions and rejects an unquoted trap loudly in typed positions (it does not silently rewrite your file). The live 1.1 footguns are elsewhere — per-action action.yml input parsing, the truthy on: key, and downstream tooling that reads the generated YAML. So this is defensive hardening against 1.1 consumers, not a claim about the runner's own parser.

The catalog is deliberately narrow: it covers only the categories where yaml-core (1.2) emits the string PLAIN and a 1.1 consumer corrupts that plain token. Everything else (true/false, null, octal/hex without separators, floats, scientific notation, big ints) is already emitted quoted-or-numeric by yaml-core, so a 1.1 consumer reads it identically — quoting those would only churn the output. Genuine JS booleans/numbers never reach this predicate because the caller guards on typeof value === "string".