Assert

Inline assertions for Telo manifests — pluggable matchers that compare actual values against expected values inside Test.Suite cases or any sequence step.

Why use this

• Manifest-native — assertions are resources, not host-language code, so they compose with the same scoping and dependency rules as the rest of your manifest.
• Drop-in matchers — Equals, Matches, Contains cover the common comparisons without writing a controller.
• Schema-aware checks — Schema validates a value against a JSON Schema; Manifest walks structured manifest data and asserts on it.
• Observability hooks — Events asserts on emitted kernel events for behaviour-level testing.

Kinds

Kind	Purpose
Assert.Equals	Assert two values are deep-equal.
Assert.Matches	Assert a string matches a regex / pattern.
Assert.Contains	Assert a collection or string contains a value.
Assert.Schema	Validate a value against a JSON Schema.
Assert.Manifest	Walk structured manifest data and assert on it.
Assert.Events	Assert on emitted kernel events.
Assert.ModuleContext	Capture the module-level context for assertions.

Exported instances

Equals, Matches, and Contains are config-free — the comparison args arrive at invoke time — so the library ships them as ready-made singletons via exports.resources. Reference them with !ref Assert.<name> (including inside a Run.Sequence step) instead of declaring an instance:

Export	Kind
Assert.equals	Assert.Equals
Assert.matches	Assert.Matches
Assert.contains	Assert.Contains

kind: Run.Sequence
metadata: { name: Check }
steps:
  - name: Total
    invoke: !ref Assert.equals
    inputs:
      actual: ${{ steps.Add.result }}
      expected: 42

The config-bearing kinds (Schema, Manifest, Events, ModuleContext) carry per-instance state, so they stay instance-per-use and are not exported as singletons.

Example

kind: Telo.Application
metadata: { name: assert-app, version: 1.0.0 }
imports:
  Assert: std/assert@latest
---
kind: Assert.Equals
metadata: { name: CheckTotal }
expected: 42
actual: !cel "resources.AddNumbers.result"

Reference

• Assert.Manifest