Reproduction for Discussion 9290 ✅ COMPLETE

Successfully created a reproduction example for GitHub discussion #9290 which demonstrates a coverage collection issue with vi.mock('./module', { spy: true }).

Discussion: #9290

The Problem

When using vi.mock('./module', { spy: true }), coverage information is not collected for the mocked module, even though the actual code is executed. However, using the more verbose manual spy approach does collect coverage correctly.

What was created

✅ New example in /examples/repro-9290/:

• src/module.ts: Simple module to be mocked
• test/short.test.ts: Uses { spy: true } → Results in 0% coverage ❌
• test/verbose.test.ts: Uses manual spy → Results in 50% coverage ✅
• README.md: Comprehensive documentation with reproduction steps
• vitest.config.ts: Configuration with v8 coverage
• package.json: Scripts for easy testing

Verified Results

# Short approach (spy: true)
module.ts |       0 |      100 |       0 |       0 | 2-6

# Verbose approach (manual spy)  
module.ts |      50 |      100 |      50 |      50 | 6

How to reproduce

cd examples/repro-9290
pnpm run coverage:short    # Shows 0% coverage
pnpm run coverage:verbose  # Shows 50% coverage

Both tests execute the same code and verify the same behavior, but only the verbose approach collects coverage.

Expected Behavior

Both approaches should collect coverage since they both execute the actual module code. The { spy: true } option should behave identically to the manual approach.

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