Jira (PUP-8192) call_function() documentation incorrect on 'Writing functions in Ruby'

[Reid Wahl (JIRA)]

Title: Message Title

Reid Wahl created an issue   Puppet / PUP-8192 call_function() documentation incorrect on 'Writing functions in Ruby' Issue Type: Bug Affects Versions: PUP 4.10.4 Assignee: Unassigned Components: DOCS Created: 2017/11/21 11:55 PM Priority: Normal Reporter: Reid Wahl The documentation for writing custom functions in Ruby states that the second argument to call_function is an array containing all arguments that will be passed to the function being called. >If you want to call another Puppet function (like include) from inside a function, use the special call_function(name, args, &block) method. ># Flatten an array of arrays of strings, then pass it to include: >def include_nested(array_of_arrays) > call_function('include', array_of_arrays.flatten) >end >The first argument must be the name of the function to call, as a string. >The second argument must be an array containing any arguments to the function. >The third argument can be a Ruby Proc, or a Puppet lambda previously captured as a Proc (see above). You can also provide a block of Ruby code using the normal block syntax. >def my_function1(a, b, &block) > # passing given Proc > call_function('my_other_function', [a, b], &block) >end >def my_function2(a, b) > # using a Ruby block > call_function('my_other_function', [a, b]) { |x| ... } >end Source: https://puppet.com/docs/puppet/5.3/functions_ruby_implementation.html#calling-other-functions In my experience, this is not accurate. Attempts to pass an array of arguments in the second position consistently failed. Details: https://gist.github.com/nrwahl2/2d580fd564794da8a685f1a965d832f9 To summarize, what I tried to do is: kernel_modules = scope['facts']['kernel_modules'] builtin_kmods = call_function('get_builtin_kmods', [kernel_modules]) The error I received is: Evaluation Error: Error while evaluating a Function Call, 'get_builtin_kmods' parameter 'kernel_modules' expects a Hash value, got Tuple $facts['kernel_modules'] is a custom fact containing a Hash[String, String] value. Based on the documentation, my call to call_function() should have sent a one-element array of arguments to the get_builtin_kmods function. Instead, it sent one argument, which was a one-element array. It worked as expected when I removed the square brackets and used builtin_kmods = call_function('get_builtin_kmods', kernel_modules) Based on this and on examples from stdlib, it seems that this implementation of call_function() takes a sequence of arguments corresponding one-to-one to what gets passed to the called function, rather than taking an array each element of which gets passed to the called function. stdlib/lib/puppet/functions/validate_legacy.rb: call_function('deprecation', 'validate_legacy', error_msg) stdlib/lib/puppet/functions/validate_legacy.rb: call_function('fail', error_msg) stdlib/lib/puppet/functions/validate_ip_address.rb: call_function('deprecation', 'validate_ip_address', "This method is deprecated, please use the stdlib validate_legacy function, with Stdlib::Compat::Ip_Address. There is further documentation for validate_legacy function in the README.") stdlib/lib/puppet/functions/is_string.rb: call_function('deprecation', 'is_string', "This method is deprecated, please use match expressions with Stdlib::Compat::String instead. They are described at https://docs.puppet.com/puppet/latest/reference/lang_data_type.html#match-expressions.") stdlib/lib/puppet/functions/is_ipv6_address.rb: call_function('deprecation', 'is_ipv4_address', "This method is deprecated, please use match expressions with Stdlib::Compat::Ipv6 instead. They are described at https://docs.puppet.com/puppet/latest/reference/lang_data_type.html#match-expressions.") stdlib/lib/puppet/functions/validate_hash.rb: call_function('deprecation', 'validate_hash', "This method is deprecated, please use the stdlib validate_legacy function, with Stdlib::Compat::Hash. There is further documentation for validate_legacy function in the README.") stdlib/lib/puppet/functions/validate_re.rb: call_function('deprecation', 'validate_re', "This method is deprecated, please use the stdlib validate_legacy function, with Pattern[]. There is further documentation for validate_legacy function in the README.") stdlib/lib/puppet/functions/validate_ipv6_address.rb: call_function('deprecation', 'validate_ipv6_address', "This method is deprecated, please use the stdlib validate_legacy function, with Stdlib::Compat::Ipv6_address. There is further documentation for validate_legacy function in the README.") stdlib/lib/puppet/functions/validate_absolute_path.rb: call_function('deprecation', 'validate_absolute_path', "This method is deprecated, please use the stdlib validate_legacy function, with Stdlib::Compat::Absolute_Path. There is further documentation for validate_legacy function in the README.") I propose that we update the documentation to reflect the actual behavior of call_function(). Add Comment   This message was sent by Atlassian JIRA (v7.0.2#70111-sha1:88534db) -- You received this message because you are subscribed to the Google Groups "Puppet Bugs" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-bugs+unsubscr...@googlegroups.com. To post to this group, send email to puppet-bugs@googlegroups.com. Visit this group at https://groups.google.com/group/puppet-bugs. For more options, visit https://groups.google.com/d/optout.