Issue #21873 has been reported by mdalessio (Mike Dalessio). ---------------------------------------- Bug #21873: `UnboundMethod#==` returns false for methods obtained via extend + unbind https://bugs.ruby-lang.org/issues/21873 * Author: mdalessio (Mike Dalessio) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- ## Description `UnboundMethod#==` returns `false` when comparing a module's instance method against the same method obtained via `Method#unbind` on a class that includes or extends that module, despite having the same owner and source location. ```ruby module MyMethods def hello = "hello" end class Base extend MyMethods end from_module = MyMethods.instance_method(:hello) from_unbind = Base.method(:hello).unbind p from_module.owner == from_unbind.owner #=> true p from_module.source_location == from_unbind.source_location #=> true p from_module.inspect == from_unbind.inspect #=> true p from_module == from_unbind #=> false (expected true) ``` ## Diagnosis `method_eq` compares method entries using `method_entry_defined_class`. For methods mixed in via `include`/`extend`, the "defined class" will be an ICLASS and not the original class/module. In the example above, `method_eq` is comparing a module's ICLASS entry against the module, and that will always be false. Related: #18798 (fixed by @ko1 in 59e389af). -- https://bugs.ruby-lang.org/