[TEST] Add dedicated tests for `ExpandGlob` type

[kakasoo]

Feature Request

• Extensions of existing features
• Propose a type that didn't exist before

Type Expectation

There is no dedicated test file for src/types/ExpandGlob.ts. Currently it is only verified indirectly through DeepStrictPick's glob tests, so dedicated tests are needed to directly verify ExpandGlob's edge cases.

Example Type

import { ExpandGlob, Equal } from '../../src';

// Basic: top-level glob
type Q1 = ExpandGlob<{ a: 1; b: 2; c: 3 }, "*">;
type A1 = Equal<Q1, "a" | "b" | "c">;

// Nested glob
type Q2 = ExpandGlob<{ a: { b: 1; c: 2 } }, "a.*">;
type A2 = Equal<Q2, "a.b" | "a.c">;

// Array inner glob
type Q3 = ExpandGlob<{ items: { id: number; name: string }[] }, "items[*].*">;
type A3 = Equal<Q3, "items[*].id" | "items[*].name">;

// Non-glob passthrough
type Q4 = ExpandGlob<{ a: { b: 1 } }, "a.b">;
type A4 = Equal<Q4, "a.b">;

Proposed Solution

Create a new test/features/ExpandGlob.ts file to test the following scenarios.

Test Requirements

All changes must include the following tests:

1. Backward Compatibility

   • All existing tests must pass
   • Add tests to verify that existing type behavior remains unchanged

2. Feature Verification

   • * (top-level glob)
   • a.* (nested glob)
   • a[*].* (array inner glob)
   • Non-glob regular key passthrough
   • Mixed glob + regular key (when passed as union)

3. Complex Type Stability

   • 3+ levels of nested glob (a.b.*)
   • Array within array glob (items[*].sub[*].*)
   • Glob applied to empty object
   • Glob on objects with branded type properties
   • Glob applied to tuple elements ([{ a: 1 }, { b: 2 }])
   • Glob applied to readonly arrays

How to verify:

npm run build:test && npm run test
npm run prettier