✨ feat(array-methods): add new Array.LastIndexOf method of Array namespace

[AshGreyG]

📝 Description

This PR adds a new method Array.LastIndexOf of namespace Array, this method is similar to Array.prototype.lastIndexOf, when the array doesn't contain the target element, this method will return -1.

🌴 PR Type

• ✨ Feature
• 🐛 Bugfix
• 🚑 Hotfix
• 💡 Doc comment
• 🧪 Test
• 📝 Document
• 🐋 Other (please describe)

🔥 Linked issues

👾 Additional context

⛳ Change log

• I have updated the changelog/next.md with my changes.

Summary by Sourcery

Add a new type-level LastIndexOf method to the Array namespace and integrate corresponding tests and script updates

New Features:

• Add Array.LastIndexOf type utility to compute the last occurrence index of an element in a tuple, returning -1 if not found

Build:

• Update lib-gen.sh script to include test cases for Array.LastIndexOf

Tests:

• Add type-level tests for Array.LastIndexOf covering empty arrays, missing elements, and nested tuples

[sourcery-ai]

Reviewer's Guide

This PR introduces a new type-level method Array.LastIndexOf in the Array namespace, implemented via a recursive conditional type that scans an array from the end to locate the last occurrence of a target element, and includes corresponding unit tests and script updates.

Class diagram for the new Array.LastIndexOf type

classDiagram
  class Array {
    <<namespace>>
  }
  class LastIndexOf {
    <<type>>
    +Arr: unknown[]
    +T: unknown
    +Count: 0[]
    +returns: number
  }
  Array <|-- LastIndexOf : type
  class IndexOf {
    <<type>>
  }
  Array <|-- IndexOf : type
  class CreateArrayFromLength {
    <<type>>
  }
  class Integer {
    <<namespace>>
  }
  class Dec {
    <<type>>
  }
  Integer <|-- Dec : type
  LastIndexOf ..> CreateArrayFromLength : uses
  LastIndexOf ..> Integer.Dec : uses
  LastIndexOf ..> IndexOf : similar pattern

Loading

File-Level Changes

Change	Details	Files
Add new LastIndexOf type definition and implementation	Added JSDoc comments and export type LastIndexOf signature Implemented recursion using Rest, Count (via CreateArrayFromLength), and Integer.Dec to compute the last index Defaulted Count to the array length for index tracking	lib/Array/index.d.ts
Extend unit tests for LastIndexOf	Added Expect<Equal<Array.LastIndexOf<...>, ...>> cases covering empty arrays, no matches, nested arrays, and multiple occurrences	test/lib-Array.test.ts
Update test generation script with LastIndexOf cases	Appended Array.LastIndexOf entry to the test_cases mapping in lib-gen.sh	test/script/lib-gen.sh

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[sourcery-ai]

Hey @AshGreyG - I've reviewed your changes and they look great!

Prompt for AI Agents

Please address the comments from this code review:
## Individual Comments

### Comment 1
<location> `test/lib-Array.test.ts:93` </location>
<code_context>
   Expect<Equal<Array.At<[], 0>, never>>,

+  // Array.LastIndexOf
+  Expect<Equal<Array.LastIndexOf<[1,2,1,2,1,3,4], 1>, 4>>,
+  Expect<Equal<Array.LastIndexOf<[], 1>, -1>>,
+  Expect<Equal<Array.LastIndexOf<[1,2,3], 0>, -1>>,
+  Expect<Equal<Array.LastIndexOf<[[],[[]],[],[]], [[]]>, 1>>,
+
 ]
</code_context>

<issue_to_address>
Missing tests for edge cases with complex types and repeated non-primitive values.

Add tests for arrays with objects, symbols, functions, and cases like different object references or NaN to ensure correct LastIndexOf behavior with complex types and tricky equality scenarios.
</issue_to_address>

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[sourcery-ai]

suggestion (testing): Missing tests for edge cases with complex types and repeated non-primitive values.

Add tests for arrays with objects, symbols, functions, and cases like different object references or NaN to ensure correct LastIndexOf behavior with complex types and tricky equality scenarios.