[ruby/irb] Add measure command

You can use "measure" command to check performance in IRB like below:

  irb(main):001:0> 3
  => 3
  irb(main):002:0> measure
  TIME is added.
  => nil
  irb(main):003:0> 3
  processing time: 0.000058s
  => 3
  irb(main):004:0> measure :off
  => nil
  irb(main):005:0> 3
  => 3

You can set "measure :on" by "IRB.conf[:MEASURE] = true" in .irbrc, and, also,
set custom performance check method:

  IRB.conf[:MEASURE_PROC][:CUSTOM] = proc { |context, code, line_no, &block|
    time = Time.now
    result = block.()
    now = Time.now
    puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
    result
  }

https://github.com/ruby/irb/commit/3899eaf2e2

1 files changed, 144 insertions, 0 deletions

diff --git a/test/irb/test_cmd.rb b/test/irb/test_cmd.rb
index bb33f535b6..6ecb5f322b 100644
--- a/test/irb/test_cmd.rb
+++ b/test/irb/test_cmd.rb
@@ -123,5 +123,149 @@ module TestIRB
       IRB.__send__(:remove_const, :IRBRC_EXT)
       IRB.const_set(:IRBRC_EXT, ext_backup)
     end
+
+    class TestInputMethod < ::IRB::InputMethod
+      attr_reader :list, :line_no
+
+      def initialize(list = [])
+        super("test")
+        @line_no = 0
+        @list = list
+      end
+
+      def gets
+        @list[@line_no]&.tap {@line_no += 1}
+      end
+
+      def eof?
+        @line_no >= @list.size
+      end
+
+      def encoding
+        Encoding.default_external
+      end
+
+      def reset
+        @line_no = 0
+      end
+    end
+
+    def test_measure
+      IRB.init_config(nil)
+      IRB.conf[:PROMPT] = {
+        DEFAULT: {
+          PROMPT_I: '> ',
+          PROMPT_S: '> ',
+          PROMPT_C: '> ',
+          PROMPT_N: '> '
+        }
+      }
+      IRB.conf[:MEASURE] = false
+      input = TestInputMethod.new([
+        "3\n",
+        "measure\n",
+        "3\n",
+        "measure :off\n",
+        "3\n",
+      ])
+      irb = IRB::Irb.new(IRB::WorkSpace.new(Object.new), input)
+      irb.context.return_format = "=> %s\n"
+      out, err = capture_output do
+        irb.eval_input
+      end
+      assert_empty err
+      assert_match(/\A=> 3\nTIME is added\.\n=> nil\nprocessing time: .+\n=> 3\n=> nil\n=> 3\n/, out)
+    end
+
+    def test_measure_enabled_by_rc
+      IRB.init_config(nil)
+      IRB.conf[:PROMPT] = {
+        DEFAULT: {
+          PROMPT_I: '> ',
+          PROMPT_S: '> ',
+          PROMPT_C: '> ',
+          PROMPT_N: '> '
+        }
+      }
+      IRB.conf[:MEASURE] = true
+      input = TestInputMethod.new([
+        "3\n",
+        "measure :off\n",
+        "3\n",
+      ])
+      irb = IRB::Irb.new(IRB::WorkSpace.new(Object.new), input)
+      irb.context.return_format = "=> %s\n"
+      out, err = capture_output do
+        irb.eval_input
+      end
+      assert_empty err
+      assert_match(/\Aprocessing time: .+\n=> 3\n=> nil\n=> 3\n/, out)
+    end
+
+    def test_measure_enabled_by_rc_with_custom
+      IRB.init_config(nil)
+      IRB.conf[:PROMPT] = {
+        DEFAULT: {
+          PROMPT_I: '> ',
+          PROMPT_S: '> ',
+          PROMPT_C: '> ',
+          PROMPT_N: '> '
+        }
+      }
+      IRB.conf[:MEASURE] = true
+      IRB.conf[:MEASURE_PROC][:CUSTOM] = proc { |line, line_no, &block|
+        time = Time.now
+        result = block.()
+        now = Time.now
+        puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
+        result
+      }
+      input = TestInputMethod.new([
+        "3\n",
+        "measure :off\n",
+        "3\n",
+      ])
+      irb = IRB::Irb.new(IRB::WorkSpace.new(Object.new), input)
+      irb.context.return_format = "=> %s\n"
+      out, err = capture_output do
+        irb.eval_input
+      end
+      assert_empty err
+      assert_match(/\Acustom processing time: .+\n=> 3\n=> nil\n=> 3\n/, out)
+    end
+
+    def test_measure_with_custom
+      IRB.init_config(nil)
+      IRB.conf[:PROMPT] = {
+        DEFAULT: {
+          PROMPT_I: '> ',
+          PROMPT_S: '> ',
+          PROMPT_C: '> ',
+          PROMPT_N: '> '
+        }
+      }
+      IRB.conf[:MEASURE] = false
+      IRB.conf[:MEASURE_PROC][:CUSTOM] = proc { |line, line_no, &block|
+        time = Time.now
+        result = block.()
+        now = Time.now
+        puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
+        result
+      }
+      input = TestInputMethod.new([
+        "3\n",
+        "measure\n",
+        "3\n",
+        "measure :off\n",
+        "3\n",
+      ])
+      irb = IRB::Irb.new(IRB::WorkSpace.new(Object.new), input)
+      irb.context.return_format = "=> %s\n"
+      out, err = capture_output do
+        irb.eval_input
+      end
+      assert_empty err
+      assert_match(/\A=> 3\nCUSTOM is added\.\n=> nil\ncustom processing time: .+\n=> 3\n=> nil\n=> 3\n/, out)
+    end
   end
 end