feat(stepfunctions): resolve payload-template .$ inside arrays and $$ context in intrinsic args

[abanna]

Two AWS States Language parity fixes in the Step Functions payload-template / intrinsic path.

1. resolveParameters now recurses into arrays

A Parameters / ItemSelector / ResultSelector payload template must resolve .$ references at any nesting depth. Previously resolveParameters recursed into nested objects but passed array elements through verbatim, so a .$ reference inside an array was never substituted.

Real-world shape this fixes — an ECS Overrides.ContainerOverrides[].Environment[].Value.$:

"Parameters": {
  "Overrides": {
    "ContainerOverrides": [
      { "Name": "app", "Environment": [ { "Name": "ID", "Value.$": "$.systemId" } ] }
    ]
  }
}

Without array recursion, Value.$ stayed literal and the launched task got an empty environment.

2. Intrinsic arguments can reference the Context Object ($$)

resolvePath / evaluateIntrinsic / resolveIntrinsicArg now thread the Context Object through, so an intrinsic argument can read $$:

States.Format('id={}', $$.Map.Item.Value.systemId)
$$.Execution.Id

Ordinary $./States.* input-only resolution is unchanged — context is null on that path, so existing behavior is preserved.

Tests

• AslExecutorArrayParamsTest — .$ resolution inside arrays.
• AslExecutorIntrinsicContextTest — $$ references in intrinsic args (and that input-only resolution still ignores context).

Built + tested in the temurin container (targeted SFN suite green).

[greptile-apps]

Greptile Summary

This PR adds two AWS States Language parity fixes to AslExecutor: resolveParameters now recurses into arrays (fixing .$ references inside nested array structures like ECS ContainerOverrides), and the Context Object ($$) is threaded through evaluateIntrinsic/resolveIntrinsicArg so intrinsic arguments like States.Format(..., $$.Map.Item.Value.x) resolve correctly.

• Array recursion: the else if (val.isObject()) guard is widened to || val.isArray(), and a new if (parameters.isArray()) block handles arrays at any depth, correctly passing through primitives unchanged.
• Context threading: a new 3-arg resolvePath overload is added; all intrinsic helpers are updated to accept and forward context; the 2-arg overload delegates with null context, preserving existing input-only resolution behavior exactly.
• Tests: two new focused unit test classes cover both features, including a regression guard confirming $$ args yield null when no context is supplied.

Confidence Score: 4/5

Safe to merge; both fixes are narrow and well-guarded, with no changes to existing call sites outside the step-functions package.

The core logic changes are correct and backward-compatible. The only issue found is that the two new test files don't follow the *ServiceTest.java naming convention from AGENTS.md — a style concern with no impact on runtime behavior.

The two new test files (AslExecutorArrayParamsTest and AslExecutorIntrinsicContextTest) should be reviewed for naming convention alignment.

Important Files Changed

Filename	Overview
src/main/java/io/github/hectorvent/floci/services/stepfunctions/AslExecutor.java	Two well-scoped fixes: array recursion in resolveParameters and Context Object threading through evaluateIntrinsic/resolveIntrinsicArg. Backward compatibility preserved via null-context guard and a 2-arg resolvePath delegate. Logic is correct.
src/test/java/io/github/hectorvent/floci/services/stepfunctions/AslExecutorArrayParamsTest.java	Covers the ECS ContainerOverrides/$. array resolution scenario well; file naming doesn't follow the *ServiceTest.java convention required by AGENTS.md.
src/test/java/io/github/hectorvent/floci/services/stepfunctions/AslExecutorIntrinsicContextTest.java	Good coverage of States.Format with mixed $/$$. args, whole-context serialisation, and the no-context regression guard; same naming-convention concern as the companion test file.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[resolveParameters\nparameters, input, context] --> B{isObject?}
    B -- yes --> C{key ends with .$?}
    C -- yes, path starts $$.  --> D[resolvePath $.+path, context]
    C -- yes, path == $$ --> E[return context]
    C -- yes, else --> F[resolvePath path, input, context ★]
    C -- no, isObject OR isArray ★ --> G[recurse resolveParameters val]
    C -- no, primitive --> H[return val as-is]
    B -- no --> I{isArray? ★}
    I -- yes --> J[for each element\nrecurse resolveParameters element]
    I -- no --> K[return parameters]

    F --> L[resolvePath\npath, root, context]
    L --> M{starts with States.*?}
    M -- yes --> N[evaluateIntrinsic\nexpr, root, context ★]
    N --> O[resolveIntrinsicArg\narg, root, context ★]
    O --> P{context != null\nand arg starts $$. ?}
    P -- yes --> Q[resolvePath $. + suffix, context]
    P -- no, $$ exact --> R[return context]
    P -- no, $.path --> S[resolvePath arg, root, context]
    P -- no, literal / number --> T[return literal node]
    P -- no, fallthrough --> U[resolvePath arg, root, context\nnested States.* intrinsic]

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flowchart TD
    A[resolveParameters\nparameters, input, context] --> B{isObject?}
    B -- yes --> C{key ends with .$?}
    C -- yes, path starts $$.  --> D[resolvePath $.+path, context]
    C -- yes, path == $$ --> E[return context]
    C -- yes, else --> F[resolvePath path, input, context ★]
    C -- no, isObject OR isArray ★ --> G[recurse resolveParameters val]
    C -- no, primitive --> H[return val as-is]
    B -- no --> I{isArray? ★}
    I -- yes --> J[for each element\nrecurse resolveParameters element]
    I -- no --> K[return parameters]

    F --> L[resolvePath\npath, root, context]
    L --> M{starts with States.*?}
    M -- yes --> N[evaluateIntrinsic\nexpr, root, context ★]
    N --> O[resolveIntrinsicArg\narg, root, context ★]
    O --> P{context != null\nand arg starts $$. ?}
    P -- yes --> Q[resolvePath $. + suffix, context]
    P -- no, $$ exact --> R[return context]
    P -- no, $.path --> S[resolvePath arg, root, context]
    P -- no, literal / number --> T[return literal node]
    P -- no, fallthrough --> U[resolvePath arg, root, context\nnested States.* intrinsic]

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_{Reviews (1): Last reviewed commit: "feat(stepfunctions): resolve payload-tem..." | Re-trigger Greptile}

[greptile-apps]

Test naming convention mismatch

AGENTS.md specifies that unit tests should follow the *ServiceTest.java naming pattern. Both new test files (AslExecutorArrayParamsTest and AslExecutorIntrinsicContextTest) use a different suffix. While AslExecutor is not technically a service, establishing an inconsistent test-naming pattern here may cause confusion when locating tests with build tooling or running focused test commands like ./mvnw test -Dtest=AslExecutor*.

Context Used: AGENTS.md (source)

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