test(composition): Add a test reproducing the composeDirective issue

[achmiel]

Summary by CodeRabbit

• Tests
  • Added regression test verifying that @composeDirective directives are correctly preserved during subgraph federation, regardless of the order in which subgraphs are processed. Confirms no warnings are emitted.

Context

This PR contains a failing test to illustrate the issue (#2920) and is not meant to be merged.

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[coderabbitai]

Walkthrough

This PR adds a Vitest regression test to the compose-directive.test.ts suite that documents and verifies a specific ordering bug in @composeDirective handling during federated schema composition. The test confirms that directive usages are correctly preserved regardless of whether a composing-only subgraph or a composing-and-applying subgraph is processed first.

Changes

Compose Directive Ordering Regression Test

Layer / File(s)	Summary
Regression test for composing-only subgraph ordering composition/tests/v1/directives/compose-directive.test.ts	New test case verifies that @composeDirective usages are not dropped when a subgraph that only composes the directive is processed before a subgraph that both composes and applies it. Test constructs two subgraphs with different directive behaviors, builds expected federated schema, asserts matching output for both orderings, and checks for zero warnings.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: adding a test that reproduces a composeDirective issue.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

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[coderabbitai]

🧹 Nitpick comments (1)

composition/tests/v1/directives/compose-directive.test.ts (1)

503-559: ⚡ Quick win

Align new constant identifiers with the project constant naming rule.

The newly introduced const bindings (composesButDoesNotApply, composesAndApplies, expected, appliesFirst, composesFirst) don’t follow the configured UPPER_SNAKE_CASE convention for constants.

As per coding guidelines: “Use UPPER_SNAKE_CASE for constants.”

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@composition/tests/v1/directives/compose-directive.test.ts` around lines 503 -
559, Rename the local constant bindings to follow UPPER_SNAKE_CASE: change
composesButDoesNotApply → COMPOSES_BUT_DOES_NOT_APPLY, composesAndApplies →
COMPOSES_AND_APPLIES, expected → EXPECTED, appliesFirst → APPLIES_FIRST, and
composesFirst → COMPOSES_FIRST; update all uses (calls to createSubgraph,
federateSubgraphsSuccess, normalizeString, schemaToSortedNormalizedString, and
the expect assertions) to refer to the new identifiers so the test compiles and
adheres to the project constant naming rule.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@composition/tests/v1/directives/compose-directive.test.ts`:
- Around line 503-559: Rename the local constant bindings to follow
UPPER_SNAKE_CASE: change composesButDoesNotApply → COMPOSES_BUT_DOES_NOT_APPLY,
composesAndApplies → COMPOSES_AND_APPLIES, expected → EXPECTED, appliesFirst →
APPLIES_FIRST, and composesFirst → COMPOSES_FIRST; update all uses (calls to
createSubgraph, federateSubgraphsSuccess, normalizeString,
schemaToSortedNormalizedString, and the expect assertions) to refer to the new
identifiers so the test compiles and adheres to the project constant naming
rule.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: a890fd18-51e7-4e9b-b693-931271973d36

📥 Commits

Reviewing files that changed from the base of the PR and between 9fa886b and 0e122c7.

📒 Files selected for processing (1)

• composition/tests/v1/directives/compose-directive.test.ts