Remove T.let from frozen constants Sorbet can now infer

[dduugg]

Removes T.let type annotations from frozen constants that Sorbet can now infer, following up on #22883 (comment: #22883 (comment)): since 0.6.13304, Sorbet infers X = A.new.freeze the same as X = A.new. This trims boilerplate and lets the annotations that remain carry more signal.

Two groups of constants qualify:

• Direct .new(...).freeze calls on non-generic classes, which infer the exact class previously declared. Pathname(...) kernel-method calls are not inferred, so those are converted to Pathname.new(...) instead.
• Pure-literal arrays (symbol/string/nil literals, including nested literal arrays), which infer as fixed-size tuple types. Tuples are subtypes of the previously declared T::Array types, and there is existing precedent for tuple-typed constants (e.g. MACOS_MODULE_NAMES in rubocops/shared/on_system_conditionals_helper.rb).

Shapes that are still not inferred through .freeze (verified against Sorbet 0.6.13316 with T.reveal_type probes) keep their T.let: plain method calls (e.g. ENV.fetch(...)), interpolated strings, hash literals, generic .new (e.g. Set.new(...) infers T::Set[T.untyped]), empty arrays, and arrays containing splats, constant references or method-call elements.

No new tests: this is a type-annotation-only change with no runtime behaviour difference (beyond equivalent Pathname construction), covered by existing typechecking and tests.

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• AI was used to generate or assist with generating this PR.

Claude Code found the candidate constants, probed which expression shapes Sorbet infers through .freeze (using temporary typed: strict files with T.reveal_type) and applied the edits. Verified locally with brew typecheck, brew style --fix --changed and brew tests --online --changed, plus manual review of the full diff.

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[Copilot]

Pull request overview

This PR reduces Sorbet annotation boilerplate by removing T.let from frozen constants that Sorbet can now infer reliably, keeping explicit annotations only where inference through .freeze is still insufficient. It also replaces Pathname(...) kernel-method calls with Pathname.new(...) in the affected constants to preserve inference.

Changes:

• Remove T.let from frozen constants where Sorbet infers the intended type (e.g., X = Klass.new.freeze, literal arrays).
• Convert Pathname("...")/Pathname(ENV.fetch(...)) to Pathname.new(...) in constants so inference works without T.let.
• Keep existing explicit T.let annotations for non-inferable shapes (e.g., composed expressions like concatenations).

Reviewed changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
Library/Homebrew/version.rb	Simplifies NULL_TOKEN constant typing by relying on inference.
Library/Homebrew/utils/github/api.rb	Removes T.let from simple frozen scope arrays and a frozen regexp constant.
Library/Homebrew/tap_constants.rb	Removes T.let from a frozen Regexp.new(...) constant.
Library/Homebrew/sorbet/tapioca/compilers/forwardables.rb	Removes T.let from frozen literal arrays of method names.
Library/Homebrew/sorbet/tapioca/compilers/cask/config.rb	Removes T.let from a frozen literal symbol array constant.
Library/Homebrew/services/subcommand/list.rb	Removes T.let from frozen trigger/field constants (including a nil element tuple).
Library/Homebrew/sandbox.rb	Removes T.let from a frozen %w[...] constant.
Library/Homebrew/rubocops/shared/install_steps_helper.rb	Removes T.let from several frozen literal symbol arrays used for validation.
Library/Homebrew/rubocops/patches.rb	Removes T.let from a frozen patch type symbol array.
Library/Homebrew/rubocops/os_depends_on.rb	Removes T.let from a frozen symbol array constant.
Library/Homebrew/rubocops/cask/uninstall_methods_order.rb	Removes T.let from a frozen metadata keys symbol array.
Library/Homebrew/os/mac/xcode.rb	Replaces Pathname(...) with ::Pathname.new(...) and removes T.let.
Library/Homebrew/livecheck/strategy/sparkle.rb	Removes T.let from a frozen literal string array constant.
Library/Homebrew/livecheck/strategy/header_match.rb	Removes T.let from a frozen literal string array constant.
Library/Homebrew/install_steps.rb	Removes T.let from a frozen %w[...] constant.
Library/Homebrew/global.rb	Replaces Pathname(...) with Pathname.new(...) for inference and removes T.let.
Library/Homebrew/github_runner_matrix.rb	Removes T.let from frozen platform/arch symbol arrays.
Library/Homebrew/extend/kernel.rb	Removes T.let from a frozen mutex constant.
Library/Homebrew/env_config.rb	Removes T.let from a frozen %w[...] falsy-values constant.
Library/Homebrew/dev-cmd/formula-analytics.rb	Removes T.let from a frozen Date.new(...) constant.
Library/Homebrew/dependable.rb	Removes T.let from a frozen reserved-tags symbol array.
Library/Homebrew/cask/dsl/caveats.rb	Removes T.let from a frozen conditional-caveats symbol array.
Library/Homebrew/cask/cask.rb	Removes T.let from a frozen %w[...] hash-keys constant.
Library/Homebrew/cask/artifact/generated_completion.rb	Removes T.let from a frozen supported-shells symbol array.
Library/Homebrew/attestation.rb	Removes T.let from a frozen DateTime.new(...) constant.

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[MikeMcQuaid]

Nice, thanks!