ExtractPlist: expand tests

[samford]

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This is a follow-up to #21335, where we modified livecheck's ExtractPlist strategy to also use url options from the livecheck block that are supported by Cask::URL's initializer. I manually tested that PR but adding tests was going to require some refactoring, so I figured I would handle it in a separate PR after merging.

This extracts the logic for creating a duplicate cask with a different artifact URL into a separate method, so we can properly test it. It's possible to exercise this in ExtractPlist.find_versions tests to some degree but isolating this code allows us to check the returned cask and ensure that this works like it should.

This also expands ExtractPlist tests, bringing coverage to 100% for both lines and branches. As part of getting to 100% coverage, I removed an old guard in find_versions that ensures cask is present, as that's covered by Sorbet and I can't exercise that condition.

I removed an existing find_versions test case which seemed to only check that Cask::CaskLoader.load works, as it wasn't testing ExtractPlist. Similarly, I removed the UnversionedCaskChecker expectations, as these tests should arguably be checking the output from ExtractPlist methods, not what's happening inside.

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One other notable change is that this raises an error if an ExtractPlist livecheck block uses a URL option that isn't supported by Cask::URL. The existing code in ExtractPlist.find_versions quietly skips over livecheck block URL options that aren't supported by Cask::URL. That works but it doesn't make the issue apparent, so it may lead to a disconnect between what the livecheck block author expects and what actually happens.

Erroring will make the issue clear and ensure that only supported options are used. In the context of ExtractPlist, the URL options are solely intended to be passed to Cask::URL, so this should be fine for now.

Outside of that, I did some light refactoring of how we approached this, maintaining the existing behavior but making some tweaks.

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Lastly, this updates the type signature for the @header value in Cask::URL and the accessor's return type. When Cask::URL.initialize is provided with a string argument for header, it creates an array containing the string. As a result, the type of @header can't be a string and will always be T.nilable(T::Array[String]. This is something that I noticed when writing tests for ExtractPlist, so I figured it wouldn't hurt to take care of it here but I can create a separate PR if needed.

[Copilot]

Pull request overview

Expands test coverage for the ExtractPlist livecheck strategy by refactoring URL-override cask creation into a dedicated method and adding fixtures to validate supported/unsupported livecheck URL options. Also tightens Sorbet typing for Cask::URL#header.

Changes:

• Add ExtractPlist.cask_with_url helper and update find_versions to use it when an alternate URL is provided.
• Expand ExtractPlist strategy specs and add new cask fixtures for livecheck URL option scenarios.
• Update Cask::URL#header Sorbet types to reflect the runtime array normalization behavior.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Library/Homebrew/livecheck/strategy/extract_plist.rb	Extracts cask URL override logic into cask_with_url and reuses it from find_versions.
Library/Homebrew/test/livecheck/strategy/extract_plist_spec.rb	Adds focused tests for cask_with_url and expands find_versions coverage.
Library/Homebrew/test/support/fixtures/cask/Casks/livecheck/livecheck-extract-plist.rb	Adjusts fixture to use url :url and updated metadata text.
Library/Homebrew/test/support/fixtures/cask/Casks/livecheck/livecheck-extract-plist-with-url.rb	New fixture to exercise livecheck URL string override behavior.
Library/Homebrew/test/support/fixtures/cask/Casks/livecheck/livecheck-extract-plist-with-supported-url-options.rb	New fixture to validate supported URL options propagation to Cask::URL.
Library/Homebrew/test/support/fixtures/cask/Casks/livecheck/livecheck-extract-plist-with-unsupported-url-options.rb	New fixture to validate erroring on unsupported URL options.
Library/Homebrew/cask/url.rb	Updates Sorbet types for @header/header to match array normalization.

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[MikeMcQuaid]

Thanks!