Issue 114 must not be default or empty for immutable array

[feO2x]

Closes #114

This pull request introduces a new assertion method, MustNotBeDefaultOrEmpty, for ImmutableArray<T> in the Light.GuardClauses library. The changes include the implementation of the assertion, unit tests, project file updates, and documentation for the new feature.

Implementation of MustNotBeDefaultOrEmpty for ImmutableArray<T>:

• Code/Light.GuardClauses/Check.MustNotBeDefaultOrEmpty.cs: Added two overloads of the MustNotBeDefaultOrEmpty method to ensure that an ImmutableArray<T> is neither default nor empty. The first overload throws an EmptyCollectionException, while the second allows the caller to provide a custom exception.

Unit tests for the new assertion:

• Code/Light.GuardClauses.Tests/CollectionAssertions/MustNotBeDefaultOrEmptyTests.cs: Created comprehensive unit tests for MustNotBeDefaultOrEmpty, covering scenarios like default arrays, empty arrays, non-empty arrays, custom exceptions, and custom messages.

Project file updates:

• Code/Light.GuardClauses/Light.GuardClauses.csproj: Added a reference to System.Collections.Immutable version 8.0.0 to support the new assertion.

Documentation for the new feature:

• Code/Plans/issue-114-must-not-be-default-or-empty-for-immutable-array.md: Documented the context, tasks, and notes for implementing the MustNotBeDefaultOrEmpty assertion for ImmutableArray<T>.

[Copilot]

Pull Request Overview

This PR implements a new assertion method MustNotBeDefaultOrEmpty for ImmutableArray<T> to avoid boxing that would occur when using existing collection assertions with IEnumerable<T>. The implementation follows the library's established patterns with two overloads - one using default exceptions and another allowing custom exception factories.

• Added MustNotBeDefaultOrEmpty extension methods for ImmutableArray<T> with both standard and custom exception overloads
• Created comprehensive unit tests covering default arrays, empty arrays, valid arrays, custom exceptions, and caller argument expressions
• Added System.Collections.Immutable package reference to support the new functionality

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
Check.MustNotBeDefaultOrEmpty.cs	Implements the two MustNotBeDefaultOrEmpty extension method overloads for ImmutableArray<T>
MustNotBeDefaultOrEmptyTests.cs	Comprehensive unit tests for both overloads covering all edge cases
Light.GuardClauses.csproj	Adds System.Collections.Immutable package reference and reorganizes existing package references
issue-114-must-not-be-default-or-empty-for-immutable-array.md	Documentation outlining the implementation plan and requirements