module T::Private::ClassUtils
Cut down version of Chalk::Tools::ClassUtils with only :replace_method functionality. Extracted to a separate namespace so the type system can be used standalone.
Public Class Methods
replace_method(mod, name, &blk)
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Replaces a method, either by overwriting it (if it is defined directly on `mod`) or by overriding it (if it is defined by one of mod's ancestors). Returns a ReplacedMethod
instance on which you can call `bind(…).call(…)` to call the original method, or `restore` to restore the original method (by overwriting or removing the override).
# File lib/types/private/class_utils.rb, line 76 def self.replace_method(mod, name, &blk) original_method = mod.instance_method(name) original_visibility = visibility_method_name(mod, name) original_owner = original_method.owner mod.ancestors.each do |ancestor| break if ancestor == mod if ancestor == original_owner # If we get here, that means the method we're trying to replace exists on a *prepended* # mixin, which means in order to supersede it, we'd need to create a method on a new # module that we'd prepend before `ancestor`. The problem with that approach is there'd # be no way to remove that new module after prepending it, so we'd be left with these # empty anonymous modules in the ancestor chain after calling `restore`. # # That's not necessarily a deal breaker, but for now, we're keeping it as unsupported. raise "You're trying to replace `#{name}` on `#{mod}`, but that method exists in a " \ "prepended module (#{ancestor}), which we don't currently support. Talk to " \ "#dev-productivity for help." end end overwritten = original_owner == mod T::Configuration.without_ruby_warnings do T::Private::DeclState.current.without_on_method_added do mod.send(:define_method, name, &blk) if blk.arity < 0 && mod.respond_to?(:ruby2_keywords, true) mod.send(:ruby2_keywords, name) end end end mod.send(original_visibility, name) new_method = mod.instance_method(name) ReplacedMethod.new(mod, original_method, new_method, overwritten, original_visibility) end
Private Class Methods
visibility_method_name(mod, name)
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`name` must be an instance method (for class methods, pass in mod.singleton_class)
# File lib/types/private/class_utils.rb, line 60 def self.visibility_method_name(mod, name) if mod.public_method_defined?(name) :public elsif mod.protected_method_defined?(name) :protected elsif mod.private_method_defined?(name) :private else raise NameError.new("undefined method `#{name}` for `#{mod}`") end end