From: daniel@...42.com Date: 2020-09-06T00:55:52+00:00 Subject: [ruby-core:99945] [Ruby master Bug#17144] Tempfile.open { ... } does not unlink the file Issue #17144 has been updated by Dan0042 (Daniel DeLorme). Austin Ziegler wrote on mailing list: > If we don���t change the behaviour, could we at least modify the documentation for `Tempfile.open` to recommend most people use `Tempfile.create`, since I don���t think that I���ve ever used it and reach for `Tempfile.open` most of the time, because of its similarity to `File.open` (and I���ve been using Ruby since 2002). That would be good, and in fact I believe improving the documentation is the best way to address this issue. ---------------------------------------- Bug #17144: Tempfile.open { ... } does not unlink the file https://bugs.ruby-lang.org/issues/17144#change-87485 * Author: Eregon (Benoit Daloze) * Status: Open * Priority: Normal * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN ---------------------------------------- ``` ruby -rtempfile -e 'Tempfile.open("txt") { |f| $path = f.path }; p File.exist?($path)' true ``` but it should be `false`. This means even after the block finishes to execute the file still exists on a disk And this might or not be addressed by finalization much later on. This is inconsistent with the resource block pattern and basically all usages of `SomeClass.open { ... }`. There are more than 10 SomeClass.open in core+stdlib, and AFAIK all these methods release all resources at the end of the block, except Tempfile.open. Since the block creates the file, it should also delete it, so there are no leftovers after the block. The (English) docs don't mention the file is kept on disk after the block: https://docs.ruby-lang.org/en/2.7.0/Tempfile.html#method-c-open I made a PR to do unlink in https://github.com/ruby/tempfile/pull/3 and some commits in ruby/ruby (notably https://github.com/ruby/ruby/commit/fa21985a7a2f8f52a8bd82bd12a724e9dca74934). However it can cause some incompatibility, if an existing usage relied on the block only closing the file descriptor but not unlink the path. See https://github.com/ruby/tempfile/issues/2#issuecomment-686323507 When integrating this change in ruby/ruby, I found that many usages expected that the file be unlinked automatically, but had to add an extra `ensure tempfile.close!` on top of the block: https://github.com/ruby/ruby/commit/e8c3872555fc85640505974e6b1c39d315572689 (later partially reverted because such libraries probably want to keep compat with older Rubies) In all of ruby/ruby I found only [2 usages](https://github.com/ruby/ruby/commit/3beecafc2cae86290a191c1e841be13f5b08795d) depending on the file to still be on disk after the block. @shugo brought to my attention that `Tempfile.create { ... }` unlinks the file (Tempfile.create seems to exist since 2.1 yet very few seem to know about it). I think the semantics of `Tempfile.create { ... }` is what the vast majority of usages want for `Tempfile.open { ... }`. `open` is the name everyone expects, so I think it's best if `Tempfile.open { ... }` also links. `create` doesn't sound like it will cleanup to me. As an optimization we can use `Tempfile.create(&block)` to implement `Tempfile.open { ... }` to avoid creating needlessly a finalizer. Found by https://github.com/ruby/spec/commit/d347e89ef6c817e469a1c25985dbd729c52b80fd and the leak detector. From https://github.com/ruby/tempfile/issues/2 So, OK to keep this change and make `Tempfile.open { ... }` do what most usages expect, even if we have to update a few usages that relied on the file to still exist after the block? -- https://bugs.ruby-lang.org/ Unsubscribe: