From 16ab236b8814538419f484ccd42387d3f3101141 Mon Sep 17 00:00:00 2001
From: mame <mame@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 14 Sep 2017 03:36:05 +0000
Subject: [PATCH] Add branch coverage for while and until statements

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59877 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 compile.c                      |  3 +++
 test/coverage/test_coverage.rb | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/compile.c b/compile.c
index 0b3890db4b..aed9bd6e78 100644
--- a/compile.c
+++ b/compile.c
@@ -4389,6 +4389,7 @@ compile_loop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popped, co
     LABEL *prev_end_label = ISEQ_COMPILE_DATA(iseq)->end_label;
     LABEL *prev_redo_label = ISEQ_COMPILE_DATA(iseq)->redo_label;
     int prev_loopval_popped = ISEQ_COMPILE_DATA(iseq)->loopval_popped;
+    VALUE branches;
 
     struct iseq_compile_data_ensure_node_stack enl;
 
@@ -4419,6 +4420,8 @@ compile_loop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popped, co
     if (tmp_label) ADD_LABEL(ret, tmp_label);
 
     ADD_LABEL(ret, redo_label);
+    DECL_BRANCH_BASE(branches, line, type == NODE_WHILE ? "while" : "until");
+    ADD_TRACE_BRANCH_COVERAGE(ret, node->nd_body ? nd_line(node->nd_body) : line, "body", branches);
     CHECK(COMPILE_POPPED(ret, "while body", node->nd_body));
     ADD_LABEL(ret, next_label);	/* next */
 
diff --git a/test/coverage/test_coverage.rb b/test/coverage/test_coverage.rb
index 5ed838e627..3b3c9c3413 100644
--- a/test/coverage/test_coverage.rb
+++ b/test/coverage/test_coverage.rb
@@ -202,4 +202,28 @@ class TestCoverage < Test::Unit::TestCase
       }
     }
   end
+
+  def test_branch_coverage_for_while_statement
+    Dir.mktmpdir {|tmp|
+      Dir.chdir(tmp) {
+        File.open("test.rb", "w") do |f|
+          f.puts 'x = 3'
+          f.puts 'while x > 0'
+          f.puts '  x -= 1'
+          f.puts 'end'
+          f.puts 'until x == 10'
+          f.puts '  x += 1'
+          f.puts 'end'
+        end
+
+        assert_in_out_err(%w[-W0 -rcoverage], <<-"end;", ["{:branches=>{[:while, 0, 2]=>{[:body, 1, 3]=>3}, [:until, 2, 5]=>{[:body, 3, 6]=>10}}}"], [])
+          ENV["COVERAGE_EXPERIMENTAL_MODE"] = "true"
+          Coverage.start(branches: true)
+          tmp = Dir.pwd
+          require tmp + '/test.rb'
+          p Coverage.result[tmp + "/test.rb"]
+        end;
+      }
+    }
+  end
 end