Ignore ObjectFieldNode ordering when checking if selections can be merged

[tobias-tengler]

No description provided.

[Copilot]

Pull Request Overview

This PR makes object value comparisons in the syntax tree ignore the ordering of input object fields when checking mergeability and updates hash‐code generation accordingly. It also adds new GraphQL tests and supporting model types to validate this behavior.

• Implement order-insensitive equality for ObjectValueNode and sort fields in GetHashCode
• Add tests (and snapshots) covering identical and conflicting input fields in various orderings
• Introduce FindDog3 and ComplexInput3 to support list-based input field tests

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/HotChocolate/Language/src/Language.SyntaxTree/SyntaxEqualityComparer.cs	Make Equals(ObjectValueNode,…) order-insensitive and sort fields for hash codes
src/HotChocolate/Core/test/Validation.Tests/snapshots/FieldSelectionMergingRuleTests.ConflictingNestedInputFieldValues.snap	New snapshot for conflicting nested input field values
src/HotChocolate/Core/test/Validation.Tests/snapshots/FieldSelectionMergingRuleTests.ConflictingNestedInputFieldListValues.snap	New snapshot for conflicting nested input field list values
src/HotChocolate/Core/test/Validation.Tests/snapshots/FieldSelectionMergingRuleTests.ConflictingInputFieldValues.snap	New snapshot for conflicting input field values
src/HotChocolate/Core/test/Validation.Tests/snapshots/FieldSelectionMergingRuleTests.ConflictingInputFieldListValues.snap	New snapshot for conflicting input field list values
src/HotChocolate/Core/test/Validation.Tests/Models/Query.cs	Add FindDog3 method to support list-based input tests
src/HotChocolate/Core/test/Validation.Tests/Models/ComplexInput3.cs	Add ComplexInput3 record for nested input-list tests
src/HotChocolate/Core/test/Validation.Tests/FieldSelectionMergingRuleTests.cs	Add new [Fact] tests covering ordering-insensitive scenarios

Comments suppressed due to low confidence (1)

src/HotChocolate/Language/src/Language.SyntaxTree/SyntaxEqualityComparer.cs:1092

• There's no existing test to assert that GetHashCode produces the same result regardless of field ordering. Adding a unit test for this would help ensure future changes don’t break this behavior.

        foreach (var field in node.Fields.OrderBy(field => field.Name.Value, StringComparer.Ordinal))

[Copilot]

This nested loop results in O(n²) comparisons for each ObjectValueNode. Consider building a lookup (e.g., a dictionary keyed by field name) for y.Fields to reduce the complexity to O(n).

Suggested change

	for (var i = 0; i < x.Fields.Count; i++)
	{
	var xField = x.Fields[i];
	ObjectFieldNode? matchingField = null;
	for (var j = 0; j < y.Fields.Count; j++)
	{
	var yField = y.Fields[j];
	if (Equals(xField.Name, yField.Name))
	{
	matchingField = yField;
	break;
	}
	}
	if (matchingField is null || !Equals(xField.Value, matchingField.Value))
	{
	var yFieldsByName = y.Fields.ToDictionary(field => field.Name, field => field);
	for (var i = 0; i < x.Fields.Count; i++)
	{
	var xField = x.Fields[i];
	if (!yFieldsByName.TryGetValue(xField.Name, out var matchingField) || !Equals(xField.Value, matchingField.Value))
	{