Issue #19371 has been updated by hsbt (Hiroshi SHIBATA). Status changed from Open to Assigned Assignee set to hsbt (Hiroshi SHIBATA) Thanks for your investigation. I got same report at https://github.com/ruby/psych/discussions/607. ---------------------------------------- Bug #19371: Having Psych 5 installed raises an error during another gem's C-extension installation when parsing YAML https://bugs.ruby-lang.org/issues/19371#change-101432 * Author: tombruijn (Tom de Bruijn) * Status: Assigned * Priority: Normal * Assignee: hsbt (Hiroshi SHIBATA) * ruby -v: ruby 3.1.2p20 (2022-04-12 revision 4491bb740a) [aarch64-linux] * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- ## Summary There's an issue on Ruby versions with Psych 4 installed by default (Ruby 2.6 through 3.1) after installing the Psych gem version 5. This problem occurs when a Ruby gem has a C-extension installation script that parses a YAML string. I'm reporting it here and not with on the Psych gem repo, because it looks more like an issue with which Ruby C-extension is load during other gem's C-extension installation. ## Background I have a gem that parses a YAML string in the C-extension installation script, or it calls `Gem.configuration[:http_proxy]`, which parses the `.gemrc` file as YAML. This triggers the error mentioned below. This YAML parsing is done in the gem's `ext/extconf.rb` file. An example gem can be found in this repository: https://github.com/tombruijn/yaml-dummy-gem, see the [`ext/extconf.rb` file](https://github.com/tombruijn/yaml-dummy-gem/blob/main/ext/extconf.rb#L3). ## The problem On Ruby 3.1.3 Psych version 4 is installed by default. When it parses the YAML file, it will use Psych 4. When Psych 5 is also installed on Ruby 3.1.3, it is no longer be able to parse the YAML file. The following error is raised: ``` $ bundle install Fetching https://github.com/tombruijn/yaml-dummy-gem.git Resolving dependencies... Using bundler 2.3.7 Using yaml-dummy-gem 1.0.0 from https://github.com/tombruijn/yaml-dummy-gem.git (at main@a48852d) Gem::Ext::BuildError: ERROR: Failed to build gem native extension. current directory: /usr/local/bundle/bundler/gems/yaml-dummy-gem-a48852dac33d/ext /usr/local/bin/ruby -I /usr/local/lib/ruby/3.1.0 -r ./siteconf20230123-730-rmbnnl.rb extconf.rb /usr/local/lib/ruby/3.1.0/psych.rb:459:in `parse_stream': undefined method `parse' for #<Psych::Parser:0x0000ffff8078c7f8 @handler=#<Psych::Handlers::DocumentStream:0x0000ffff8078c910 @stack=[], @last=nil, @root=nil, @start_line=nil, @start_column=nil, @end_line=nil, @end_column=nil, @block=#<Proc:0x0000ffff8078c848 /usr/local/lib/ruby/3.1.0/psych.rb:399>>, @external_encoding=0> (NoMethodError) parser.parse yaml, filename ^^^^^^ from /usr/local/lib/ruby/3.1.0/psych.rb:399:in `parse' from extconf.rb:3:in `<main>' extconf failed, exit code 1 Gem files will remain installed in /usr/local/bundle/bundler/gems/yaml-dummy-gem-a48852dac33d for inspection. Results logged to /usr/local/bundle/bundler/gems/extensions/aarch64-linux/3.1.0/yaml-dummy-gem-a48852dac33d/gem_make.out /usr/local/lib/ruby/3.1.0/rubygems/ext/builder.rb:95:in `run' /usr/local/lib/ruby/3.1.0/rubygems/ext/ext_conf_builder.rb:47:in `block in build' /usr/local/lib/ruby/3.1.0/tempfile.rb:317:in `open' /usr/local/lib/ruby/3.1.0/rubygems/ext/ext_conf_builder.rb:26:in `build' /usr/local/lib/ruby/3.1.0/rubygems/ext/builder.rb:161:in `build_extension' /usr/local/lib/ruby/3.1.0/rubygems/ext/builder.rb:195:in `block in build_extensions' /usr/local/lib/ruby/3.1.0/rubygems/ext/builder.rb:192:in `each' /usr/local/lib/ruby/3.1.0/rubygems/ext/builder.rb:192:in `build_extensions' /usr/local/lib/ruby/3.1.0/rubygems/installer.rb:853:in `build_extensions' /usr/local/lib/ruby/3.1.0/bundler/rubygems_gem_installer.rb:71:in `build_extensions' /usr/local/lib/ruby/3.1.0/bundler/source/path/installer.rb:34:in `post_install' /usr/local/lib/ruby/3.1.0/bundler/source/path.rb:244:in `generate_bin' /usr/local/lib/ruby/3.1.0/bundler/source/git.rb:194:in `install' /usr/local/lib/ruby/3.1.0/bundler/installer/gem_installer.rb:54:in `install' /usr/local/lib/ruby/3.1.0/bundler/installer/gem_installer.rb:16:in `install_from_spec' /usr/local/lib/ruby/3.1.0/bundler/installer/parallel_installer.rb:186:in `do_install' /usr/local/lib/ruby/3.1.0/bundler/installer/parallel_installer.rb:177:in `block in worker_pool' /usr/local/lib/ruby/3.1.0/bundler/worker.rb:62:in `apply_func' /usr/local/lib/ruby/3.1.0/bundler/worker.rb:57:in `block in process_queue' /usr/local/lib/ruby/3.1.0/bundler/worker.rb:54:in `loop' /usr/local/lib/ruby/3.1.0/bundler/worker.rb:54:in `process_queue' /usr/local/lib/ruby/3.1.0/bundler/worker.rb:91:in `block (2 levels) in create_threads' An error occurred while installing yaml-dummy-gem (1.0.0), and Bundler cannot continue. In Gemfile: yaml-dummy-gem ``` ## Debugging results The error is raised because the `Psych::Parser#parse` method cannot be found. In Psych version 4, this method is [defined by the Psych C-extension](https://github.com/ruby/psych/blob/2c3708e0a483c6d44ebddaff0b524166f3e7bc78/...). In Psych version 5 the `parse` method is [defined in the gem's Ruby code](https://github.com/ruby/psych/blob/1f23e6e7f0ab4a6efab598c1ee528bb52d40ee51/...). This method calls a [C function registered as the private `_native_parse` method](https://github.com/ruby/psych/blob/1f23e6e7f0ab4a6efab598c1ee528bb52d40ee51/...), which is the renamed version of the `parse` C-function in Psych version 4. From what I can tell, the Psych version 4 C-extension is no longer loaded when Psych version 5 is installed in this scenario. There is a mix up in which Psych gem version's C-extension is loaded during my dummy gem's C-extension installation. It load the Psych 4 Ruby code, with the Psych 5 C-extension∂. I confirmed this by modifying the standard installed Psych gem's code on Ruby 3.1 (Docker image `ruby:3.1`), with the following the change, which prints `true` on error. This means the Psych 4 gem has the Psych 5 C-extension loaded where `_native_parse` is defined. ```diff diff --git lib/psych.rb lib/psych.rb index 42d79ef..1a690d2 100644 --- lib/psych.rb +++ lib/psych.rb @@ -452,6 +452,9 @@ def self.parser def self.parse_stream yaml, filename: nil, &block if block_given? parser = Psych::Parser.new(Handlers::DocumentStream.new(&block)) + # This returns `true`, but it should be `false`. The `_native_parse` + # method is defined in the Psych 5 C-extension, not Psych 4. + puts parser.respond_to? :_native_parse, true # => true parser.parse yaml, filename ``` This error only occurs during the gem's extension installation in `ext/extconf.rb`. If the gem parses YAML when a Ruby app is running, it will not produce the same error with Psych version 5 installed. This issue does not occur on Ruby 3.2, where Psych version 5 is installed by default. I have confirmed this error occurs on the latest patch releases of the following Ruby versions: 3.1, 3.0, 2.7 and 2.6. ``` $ gem list psych psych (5.0.2, default: 4.0.3) ``` ## Code to reproduce Here is a basic Ruby gem that only parses a YAML file during extension installation: https://github.com/tombruijn/yaml-dummy-gem Here is a small project that triggers the error: https://github.com/tombruijn/yaml-dummy-ruby-app A GitHub actions workflow shows the results for all affected Ruby versions: https://github.com/tombruijn/yaml-dummy-ruby-app/actions/runs/3969088933 The [example app repo](https://github.com/tombruijn/yaml-dummy-ruby-app) also has instructions to run the example app locally. Please follow the instructions in the README to see the error. -- https://bugs.ruby-lang.org/