# Eco-tests (indexer contract) (/docs/internals/eco-tests)

`eco-tests/` is a standalone crate (excluded from the cargo workspace) that
pins the **storage shapes and runtime API signatures the TAO.com ecosystem
indexer depends on**. The indexer reads chain state directly — storage items
like `Consensus`, `Incentive`, `Weights`, `Bonds`, ownership and childkey
maps, and runtime APIs like `DelegateInfoRuntimeApi` and
`StakeInfoRuntimeApi`. If a runtime change renames a storage item, changes a
value type, or alters an API return shape, the indexer breaks in production
even though nothing in this repo's own tests would notice.

The tests are intentionally shallow: they mostly assert that each pinned
storage item still exists with the expected key and value types (the test
body is often just a typed `::get()` call that must compile) and that the
runtime API signatures are unchanged. A compile failure *is* the signal.

## Running them [#running-them]

The crate is excluded from the workspace, so run from its own directory:

```bash
cd eco-tests
SKIP_WASM_BUILD=1 cargo test
```

CI runs this on every PR (`eco-tests.yml`).

## When one fails on your PR [#when-one-fails-on-your-pr]

A failure means your change breaks the data contract the indexer consumes.
Two valid resolutions:

1. **Unintended breakage** — adjust your change to preserve the storage/API
   shape (e.g. keep the old item alongside the new one, or provide a
   migration plus an unchanged read path).
2. **Intentional change** — update the eco-test to the new shape. Any PR that
   touches `eco-tests/**` automatically requests review from the indexer
   liaison (`eco-tests-indexer-notify.yml`), so the indexer team hears about
   the change before it ships. Don't merge until they've acknowledged it.

What you should **not** do is silently change the assertion to make CI green:
the whole point of the suite is that the notification fires and the indexer
team gets lead time.