Ruby: add methods KernAux.supports_*?

pkgs/ruby/lib/kernaux.rb

@@ -65,7 +65,7 @@ module KernAux
 
   # @!parse [ruby]
 
-  if singleton_class.method_defined? :snprintf1
+  if Version.supports_printf?
     ##
     # Typical `printf`.
     #
@@ -127,8 +127,7 @@ module KernAux
   # @return [Array<String>] command line arguments
   #
   # @raise [CmdlineError] syntax is invalid
-
-  # @!parse [ruby]
+  ##
 
   ##
   # @!method utoa(number, base, prefix)

pkgs/ruby/lib/kernaux/file.rb

@@ -2,7 +2,7 @@
 
 # rubocop:disable Lint/EmptyClass
 
-if defined? KernAux::File
+if KernAux::Version.supports_file?
   module KernAux
     ##
     # File simulator.

pkgs/ruby/lib/kernaux/version.rb

@@ -3,4 +3,62 @@
 module KernAux
   # Gem version.
   VERSION = '0.3.0'
+
+  ##
+  # This module includes functions to determine if specific features are
+  # supported by the library.
+  #
+  module Version
+    def self.supports_cmdline?
+      KernAux.singleton_class.method_defined? :cmdline
+    end
+
+    def self.supports_file?
+      defined? KernAux::File
+    end
+
+    def self.supports_itoa?
+      KernAux.singleton_class.method_defined? :itoa
+    end
+
+    def self.supports_itoa2?
+      KernAux.singleton_class.method_defined? :itoa2
+    end
+
+    def self.supports_itoa8?
+      KernAux.singleton_class.method_defined? :itoa8
+    end
+
+    def self.supports_itoa10?
+      KernAux.singleton_class.method_defined? :itoa10
+    end
+
+    def self.supports_itoa16?
+      KernAux.singleton_class.method_defined? :itoa16
+    end
+
+    def self.supports_printf?
+      KernAux.singleton_class.method_defined? :snprintf1
+    end
+
+    def self.supports_utoa?
+      KernAux.singleton_class.method_defined? :utoa
+    end
+
+    def self.supports_utoa2?
+      KernAux.singleton_class.method_defined? :utoa2
+    end
+
+    def self.supports_utoa8?
+      KernAux.singleton_class.method_defined? :utoa8
+    end
+
+    def self.supports_utoa10?
+      KernAux.singleton_class.method_defined? :utoa10
+    end
+
+    def self.supports_utoa16?
+      KernAux.singleton_class.method_defined? :utoa16
+    end
+  end
 end

pkgs/ruby/spec/lib/kernaux/cmdline_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.cmdline' do
-  if described_class.singleton_class.method_defined? :cmdline
+KernAux::Version.supports_cmdline? and RSpec.describe KernAux, '.cmdline' do
   subject(:cmdline) { described_class.cmdline str }
 
   let(:str) { 'foo bar\\ baz "car cdr"' }
@@ -91,5 +90,4 @@ RSpec.describe KernAux, '.cmdline' do
         raise_error described_class::CmdlineError, 'buffer overflow'
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/itoa10_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.itoa10' do
-  if described_class.singleton_class.method_defined? :itoa10
+KernAux::Version.supports_itoa10? and RSpec.describe KernAux, '.itoa10' do
   subject(:itoa10) { described_class.itoa10 number }
 
   let(:number) { rand((-2**63)..(2**63 - 1)) }
@@ -59,5 +58,4 @@ RSpec.describe KernAux, '.itoa10' do
         RangeError, 'bignum too big to convert into `long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/itoa16_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.itoa16' do
-  if described_class.singleton_class.method_defined? :itoa16
+KernAux::Version.supports_itoa16? and RSpec.describe KernAux, '.itoa16' do
   subject(:itoa16) { described_class.itoa16 number }
 
   let(:number) { rand((-2**63)..(2**63 - 1)) }
@@ -61,5 +60,4 @@ RSpec.describe KernAux, '.itoa16' do
         RangeError, 'bignum too big to convert into `long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/itoa2_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.itoa2' do
-  if described_class.singleton_class.method_defined? :itoa2
+KernAux::Version.supports_itoa2? and RSpec.describe KernAux, '.itoa2' do
   subject(:itoa2) { described_class.itoa2 number }
 
   let(:number) { rand((-2**63)..(2**63 - 1)) }
@@ -61,5 +60,4 @@ RSpec.describe KernAux, '.itoa2' do
         RangeError, 'bignum too big to convert into `long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/itoa8_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.itoa8' do
-  if described_class.singleton_class.method_defined? :itoa8
+KernAux::Version.supports_itoa8? and RSpec.describe KernAux, '.itoa8' do
   subject(:itoa8) { described_class.itoa8 number }
 
   let(:number) { rand((-2**63)..(2**63 - 1)) }
@@ -61,5 +60,4 @@ RSpec.describe KernAux, '.itoa8' do
         RangeError, 'bignum too big to convert into `long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/itoa_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.itoa' do
-  if described_class.singleton_class.method_defined? :itoa
+KernAux::Version.supports_itoa? and RSpec.describe KernAux, '.itoa' do
   subject(:itoa) { described_class.itoa number, base, prefix }
 
   let(:number) { rand((-2**63)..(2**63 - 1)) }
@@ -234,5 +233,4 @@ RSpec.describe KernAux, '.itoa' do
       )
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/utoa10_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.utoa10' do
-  if described_class.singleton_class.method_defined? :utoa10
+KernAux::Version.supports_utoa10? and RSpec.describe KernAux, '.utoa10' do
   subject(:utoa10) { described_class.utoa10 number }
 
   let(:number) { rand 0..(2**64 - 1) }
@@ -41,5 +40,4 @@ RSpec.describe KernAux, '.utoa10' do
         RangeError, 'bignum too big to convert into `unsigned long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/utoa16_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.utoa16' do
-  if described_class.singleton_class.method_defined? :utoa16
+KernAux::Version.supports_utoa16? and RSpec.describe KernAux, '.utoa16' do
   subject(:utoa16) { described_class.utoa16 number }
 
   let(:number) { rand 0..(2**64 - 1) }
@@ -41,5 +40,4 @@ RSpec.describe KernAux, '.utoa16' do
         RangeError, 'bignum too big to convert into `unsigned long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/utoa2_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.utoa2' do
-  if described_class.singleton_class.method_defined? :utoa2
+KernAux::Version.supports_utoa2? and RSpec.describe KernAux, '.utoa2' do
   subject(:utoa2) { described_class.utoa2 number }
 
   let(:number) { rand 0..(2**64 - 1) }
@@ -41,5 +40,4 @@ RSpec.describe KernAux, '.utoa2' do
         RangeError, 'bignum too big to convert into `unsigned long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/utoa8_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.utoa8' do
-  if described_class.singleton_class.method_defined? :utoa8
+KernAux::Version.supports_utoa8? and RSpec.describe KernAux, '.utoa8' do
   subject(:utoa8) { described_class.utoa8 number }
 
   let(:number) { rand 0..(2**64 - 1) }
@@ -41,5 +40,4 @@ RSpec.describe KernAux, '.utoa8' do
         RangeError, 'bignum too big to convert into `unsigned long long\''
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/ntoa/utoa_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.utoa' do
-  if described_class.singleton_class.method_defined? :utoa
+KernAux::Version.supports_utoa? and RSpec.describe KernAux, '.utoa' do
   subject(:utoa) { described_class.utoa number, base, prefix }
 
   let(:number) { rand 0..(2**64 - 1) }
@@ -206,5 +205,4 @@ RSpec.describe KernAux, '.utoa' do
       )
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/printf/snprintf1_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.snprintf1' do
-  if described_class.singleton_class.method_defined? :snprintf1
+KernAux::Version.supports_printf? and RSpec.describe KernAux, '.snprintf1' do
   let(:size) { 10_000 }
 
   context 'with 0 arguments' do
@@ -278,5 +277,4 @@ RSpec.describe KernAux, '.snprintf1' do
       end
     end
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/printf/sprintf1_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.sprintf1' do
-  if described_class.singleton_class.method_defined? :sprintf1
+KernAux::Version.supports_printf? and RSpec.describe KernAux, '.sprintf1' do
   context 'with 1 argument' do
     subject(:sprintf1) { described_class.sprintf1 format }
 
@@ -24,5 +23,4 @@ RSpec.describe KernAux, '.sprintf1' do
     it { is_expected.to be_frozen }
     it { is_expected.to eq described_class.snprintf1(100, format, arg).first }
   end
-  end
 end

pkgs/ruby/spec/lib/kernaux/printf/sprintf_spec.rb

@@ -2,8 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe KernAux, '.sprintf' do
-  if described_class.singleton_class.method_defined? :sprintf
+KernAux::Version.supports_printf? and RSpec.describe KernAux, '.sprintf' do
   subject :sprintf do
     described_class.sprintf 'Hello, ', ['%s', 'World'], '!'
   end
@@ -51,5 +50,4 @@ RSpec.describe KernAux, '.sprintf' do
       end
     end
   end
-  end
 end