Add option --dont-start and make current profile available as RubyProf::Profile.current

bin/ruby-prof

@@ -45,6 +45,7 @@ module RubyProf
   #                                       self - Self time
   #                                       wait - Wait time
   #                                       child - Child time
+  #        --start-paused               Pause the profile immediately (resume manually with RubyProf::Profile.current.resume)
   #        --track_allocations          Track allocations while profiling
   #    -v, --version version            Show version (1.1.0)
   #    -h, --help                       Show help message
@@ -73,6 +74,7 @@ module RubyProf
       options.pre_libs = Array.new
       options.pre_execs = Array.new
       options.printer = RubyProf::FlatPrinter
+      options.start_paused = false
       options.track_allocations = false
     end
 
@@ -232,6 +234,10 @@ module RubyProf
                                 end
         end
 
+        opts.on('--start-paused', "Pause the profile immediately (resume manually with RubyProf::Profile.current.resume)") do
+          options.start_paused = true
+        end
+
         opts.on('--track_allocations', 'Track allocations while profiling') do
           options.track_allocations = true
         end
@@ -299,8 +305,9 @@ module RubyProf
       end
 
       script = ARGV.shift
-      profile.profile do
-       load script
+
+      profile.profile paused: options.start_paused do
+        load script
       end
     end
   end

ext/ruby_prof/rp_profile.c

@@ -634,8 +634,16 @@ static VALUE prof_profile_track_allocations(VALUE self)
    start -> self
 
    Starts recording profile data.*/
-static VALUE prof_start(VALUE self)
+static VALUE prof_start(int argc, VALUE* argv, VALUE self)
 {
+    VALUE keywords;
+    rb_scan_args_kw(RB_SCAN_ARGS_KEYWORDS, argc, argv, ":", &keywords);
+
+    ID table[] = {rb_intern("paused")};
+    VALUE values[1];
+    rb_get_kwargs(keywords, table, 0, 1, values);
+    VALUE paused = values[0] == Qundef ? Qfalse : values[0];
+
     char* trace_file_name;
 
     prof_profile_t* profile = prof_get_profile(self);
@@ -646,7 +654,7 @@ static VALUE prof_start(VALUE self)
     }
 
     profile->running = Qtrue;
-    profile->paused = Qfalse;
+    profile->paused = paused;
     profile->last_thread_data = threads_table_insert(profile, rb_fiber_current());
 
     /* open trace file if environment wants it */
@@ -668,6 +676,8 @@ static VALUE prof_start(VALUE self)
         }
     }
 
+    rb_iv_set(cProfile, "@current", self);
+
     prof_install_hook(self);
     return self;
 }
@@ -749,6 +759,8 @@ static VALUE prof_stop(VALUE self)
     profile->running = profile->paused = Qfalse;
     profile->last_thread_data = NULL;
 
+    rb_iv_set(cProfile, "@current", Qnil);
+
     return self;
 }
 
@@ -805,7 +817,7 @@ static VALUE prof_remove_thread(VALUE self, VALUE thread)
        ..
      end
 */
-static VALUE prof_profile_instance(VALUE self)
+static VALUE prof_profile_instance(int argc, VALUE* argv, VALUE self)
 {
     int result;
     prof_profile_t* profile = prof_get_profile(self);
@@ -815,7 +827,7 @@ static VALUE prof_profile_instance(VALUE self)
         rb_raise(rb_eArgError, "A block must be provided to the profile method.");
     }
 
-    prof_start(self);
+    prof_start(argc, argv, self);
     rb_protect(rb_yield, self, &result);
     self = prof_stop(self);
 
@@ -841,7 +853,7 @@ static VALUE prof_profile_instance(VALUE self)
 */
 static VALUE prof_profile_class(int argc, VALUE* argv, VALUE klass)
 {
-    return prof_profile_instance(rb_class_new_instance(argc, argv, cProfile));
+    return prof_profile_instance(0, NULL, rb_class_new_instance(argc, argv, cProfile));
 }
 
 /* call-seq:
@@ -912,8 +924,8 @@ void rp_init_profile(void)
 
     rb_define_singleton_method(cProfile, "profile", prof_profile_class, -1);
     rb_define_method(cProfile, "initialize", prof_initialize, -1);
-    rb_define_method(cProfile, "profile", prof_profile_instance, 0);
-    rb_define_method(cProfile, "start", prof_start, 0);
+    rb_define_method(cProfile, "profile", prof_profile_instance, -1);
+    rb_define_method(cProfile, "start", prof_start, -1);
     rb_define_method(cProfile, "stop", prof_stop, 0);
     rb_define_method(cProfile, "resume", prof_resume, 0);
     rb_define_method(cProfile, "pause", prof_pause, 0);

lib/ruby-prof/profile.rb

@@ -4,6 +4,10 @@
 
 module RubyProf
   class Profile
+    class << self
+      attr_accessor :current
+    end
+
     def measure_mode_string
       case self.measure_mode
         when WALL_TIME

test/profile_test.rb

@@ -5,6 +5,24 @@
 require_relative './call_tree_builder'
 
 class ProfileTest < TestCase
+  def test_current
+    profile = RubyProf::Profile.new
+    refute_same(profile, RubyProf::Profile.current)
+
+    yielded = false
+    profile.profile do
+      yielded = true
+      assert_same(profile, RubyProf::Profile.current)
+    end
+    assert(yielded)
+    assert_nil(RubyProf::Profile.current)
+
+    profile.start
+    assert_same(profile, RubyProf::Profile.current)
+    profile.stop
+    assert_nil(RubyProf::Profile.current)
+  end
+
   def test_measure_mode
     profile = RubyProf::Profile.new(:measure_mode => RubyProf::PROCESS_TIME)
     assert_equal(RubyProf::PROCESS_TIME, profile.measure_mode)