Pact Contract Companion (VS Code)

Lists consumer-provider Pact contract files in your workspace in a sidebar tree, and flags two real, static issues per interaction — no Pact Broker, no network call, no live verification run required.

v0.1, new niche. Not a port from the Gap Hunter Labs IntelliJ- family catalog. Evidence: no VS Code extension inspects Pact contract files for authoring issues at rest — existing Pact tooling for editors targets running consumer/provider tests, not reviewing the .json contract files already checked into (or generated into) the workspace.

Real schema, not a guess

The two Pact contract shapes this extension parses were verified against real, captured example files fetched directly from GitHub (not a paraphrased description): a spec v2 fixture from gitlabhq/gitlabhq (singular providerState string) and a spec v3 fixture from pact-foundation/pact_broker (providerStates array of {name, params}). Both forms are normalized to the same internal shape.

What it does

A Pact Contracts view in the Explorer sidebar lists every file matching pactContractCompanion.contractGlob (default: **/pacts/**/*.json) that actually looks like a Pact contract (has consumer, provider, and interactions) — other JSON files matching the glob are silently skipped, not treated as errors. Each contract shows its interaction count and expands to show two kinds of finding:

• No provider state declared. Not inherently wrong — plenty of real requests need no precondition — but worth a glance, since it's a common oversight when a provider's response actually does depend on state nobody wrote down.
• Duplicate interaction (same description + same provider state appearing more than once in one contract file). This is not a cosmetic nit: Pact's own mock-service matching uses the (description, provider state) pair as an interaction's identity, so a duplicate pair means one of the two interactions silently overwrote the other — it looks like two tests exist, but only one ever actually ran.

v0.1 scope, honestly noted

• Static analysis of contract files already on disk only. No connection to a Pact Broker, so it can't tell you whether a contract has actually been verified by the provider yet — that would need a broker (or CI-published) connection this v0.1 doesn't make.
• Two checks, not the full range of things a linter for Pact contracts could eventually catch (e.g. matching-rule sanity, response-shape drift between versions of the same contract).

Development

npm install
npm run compile   # or: npm run watch
npm test

To build an installable package without publishing:

npx @vscode/vsce package

License

Apache License 2.0 — see LICENSE.