Issue #20043 has been updated by ko1 (Koichi Sasada). Here is a survey which node (in Prism) are used in `defined?(expr)` (the node of `expr`) https://gist.github.com/ko1/b31517a5037d55bbe50e7f12d79b9fc1 I understand the usage of :constant_read_node, :constant_path_node, :instance_variable_read_node, :call_node, :global_variable_read_node, :class_variable_read_node, :forwarding_super_node, :numbered_reference_read_node, :yield_node, :super_node, but not sure other nodes. https://gist.github.com/ko1/fcf98c0fec3aecfdae7f1a4d91ee5626 is a survey of other nodes. There are misusages like `defined? C ? x : y` (expected `defined?(C) ? x : y` but `defined?(C ? x : y)` which always returns `"expression"`. ---------------------------------------- Bug #20043: `defined?` checks for method existence but only sometimes https://bugs.ruby-lang.org/issues/20043#change-108721 * Author: tenderlovemaking (Aaron Patterson) * Status: Open * ruby -v: ruby 3.3.0dev (2023-12-05T21:25:34Z master 56eccb350b) [arm64-darwin23] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- When an expression is passed to `defined?`, it will _sometimes_ check if a method in a sub-expression is defined and sometimes it won't. For example: ``` $ ./miniruby -e'p defined?(a)' nil $ ./miniruby -e'p defined?([a])' nil ``` In the above case, Ruby will check whether or not the method `a` is defined, and it returns `nil`. However, if you use a splat, it will not check: ``` $ ./miniruby -e'p defined?([*a])' "expression" ``` The same thing seems to happen with method parameters: ``` $ ./miniruby -e'p defined?(itself)' "method" $ ./miniruby -e'p defined?(itself(a))' nil $ ./miniruby -e'p defined?(itself(*a))' "method" ``` Oddly, `defined?` will check contents of arrays, but _won't_ check contents of hashes: ``` $ ./miniruby -e'p defined?([[[[a]]]])' nil $ ./miniruby -e'p defined?({ a => a })' "expression" ``` I think all of the cases that refer to `a` should check whether or not `a` is defined regardless of splats or hashes. ---Files-------------------------------- clipboard-202312191405-owvpy.png (27.3 KB) general - ruby-lang - 4 new items - Slack 2023-12-19 16-10-39.png (100 KB) -- https://bugs.ruby-lang.org/