fix(expect): reject nullish toHaveProperty subjects (fix #10735)

[mrfandu1]

Description

expect(null).toHaveProperty('x') crashed with a raw internal error —
TypeError: Cannot convert undefined or null to object pointing into Vitest
internals — because getValue() called Object.hasOwn(actual, propertyName)
before the null-safe utils.getPathInfo fallback could run. The negated form
expect(null).not.toHaveProperty('x') crashed the same way.

Per @sheremet-va's guidance in the issue, both forms now throw a clear matcher
error instead:

TypeError: .toHaveProperty() expects to receive an object, but got null

The wording matches the existing .toMatch() error style in the same file.
The .not form also throws rather than passing because asserting properties
on a nullish subject is a test error; expect(x).toBeDefined() should come
first.

Resolves #10735

Disclosure: I used Claude Code to help develop this fix. I reviewed the
change and ran the listed checks before submitting.

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Tests

• Run the tests with pnpm test:ci.

Verification performed:

• CI=true pnpm test jest-expect.test.ts
  • 342 passed and 27 expected failures across forks, threads, and vmThreads.
• pnpm typecheck
• pnpm lint
• pnpm build
• pnpm test:ci
  • The affected suite passed. The broader local Windows run encountered unrelated coverage and workspace test failures involving coverage-directory races, timeouts, and existing snapshot differences.

Documentation

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No documentation changes are needed for this bug fix.

Changesets

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[Copilot]

Pull request overview

Fixes Vitest’s Jest-compat .toHaveProperty() matcher to handle null/undefined subjects by throwing a clear, user-facing matcher error instead of bubbling an internal Object.hasOwn TypeError.

Changes:

• Add an explicit nullish guard in .toHaveProperty() that throws TypeError: .toHaveProperty() expects to receive an object, but got ….
• Add unit tests covering both positive and negated (.not) forms for null and undefined, including the “expected value” overload.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
test/unit/test/jest-expect.test.ts	Adds regression tests ensuring nullish .toHaveProperty() usage throws a clear matcher error (incl. .not).
packages/expect/src/jest-expect.ts	Introduces a nullish subject guard in toHaveProperty to prevent internal crashes and provide a consistent TypeError message.

[mrfandu1]

This is my account and I personally reviewed all the code and tests here before opening the PR. I’ve read through #10735 and the discussion, the earlier related PRs, and the contribution guidelines. I did use Claude Code to help with the fix, but I stand behind everything in it.