[michaelstaib]

Fixes #10222

[Copilot]

Pull request overview

Fixes Fusion composition post-merge validation crashing on spec-lawful bare enum (and object) defaults supplied for list-typed arguments/fields by applying GraphQL list input coercion and hardening type handling to avoid invalid casts.

Changes:

• Add list input coercion handling in EnumTypeDefaultValueInaccessibleRule.ValidateDefaultValue so non-list default values on list types validate against the element type.
• Replace unsafe casts with type checks to prevent InvalidCastException and ignore undeclared input object fields during traversal.
• Add regression tests covering bare enum defaults on list types (both accessible and inaccessible cases) plus object-default edge cases.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/HotChocolate/Fusion/src/Fusion.Composition/PostMergeValidationRules/EnumTypeDefaultValueInaccessibleRule.cs	Implements list input coercion and safe type checks to prevent crashes and correctly validate inaccessible enum references.
src/HotChocolate/Fusion/test/Fusion.Composition.Tests/PostMergeValidationRules/EnumTypeDefaultValueInaccessibleRuleTests.cs	Adds regression coverage for bare enum/object defaults on list-typed inputs and verifies expected diagnostics.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[github-actions]

Patch coverage

71.4% of changed lines covered (15/21)

File	Covered	Changed	Patch %
…/EnumTypeDefaultValueInaccessibleRule.cs	15	21	71.4% 🔴

Uncovered changed lines (JSON)

{
  "sha": "1461fbe0916f1c3b3d3ed0edb4fc93dda42c62c0",
  "files": [
    { "path": "src/HotChocolate/Fusion/src/Fusion.Composition/PostMergeValidationRules/EnumTypeDefaultValueInaccessibleRule.cs", "ranges": [[87, 88], [103, 104], [119, 120]] }
  ]
}

---

Project coverage: 54.5% (243366/446649 lines)