Issue #21091 has been updated by rrotter (Ryan Rotter). I would agree with your assessment if requiring both names of the same file sequentially loaded it twice, but ruby is detecting and handling this when it's not recursive. The following code works as expected: ``` # returns true require '/tmp/foo' # returns false require '/tmp/FOO' ``` ---------------------------------------- Bug #21091: recursive require not detected on case insensitive filesystem https://bugs.ruby-lang.org/issues/21091#change-111667 * Author: rrotter (Ryan Rotter) * Status: Third Party's Issue * ruby -v: ruby 3.4.1 (2024-12-25 revision 48d4efcb85) +PRISM [arm64-darwin24] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- On case insensitive filesystems `require`ing a file from itself causes the file to be `require`d twice if the initial `require` and the `require` inside the file have different capitalization. I expect the second `require` to return false, and not execute the file a second time. ``` ~ % cat /tmp/foo.rb puts "loading #{__FILE__}" require "/tmp/foo" SOME_GLOBAL = "foobar".freeze ~ % ruby -r/tmp/FOO loading /tmp/FOO.rb loading /tmp/foo.rb /tmp/FOO.rb:3: warning: already initialized constant SOME_GLOBAL /tmp/foo.rb:3: warning: previous definition of SOME_GLOBAL was here ``` This is on macOS 15.1.1, using the default case-insensitive APFS, and ruby 3.4.1. -- https://bugs.ruby-lang.org/