merge revision(s) 65974: [Backport #15340]

	Normalize month-mday before finding epoch

	Especially over the year 2038, 30 Feb and so on may cause odd behavior
	on validating found epoch with given year-month-day [Bug #15340]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@66839 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 23 insertions, 0 deletions

diff --git a/test/ruby/test_time.rb b/test/ruby/test_time.rb
index faeff8ded3..5ddcc9dcfe 100644
--- a/test/ruby/test_time.rb
+++ b/test/ruby/test_time.rb
@@ -1056,6 +1056,29 @@ class TestTime < Test::Unit::TestCase
       assert_equal(min, t.min)
       assert_equal(sec, t.sec)
     }
+    assert_equal(Time.local(2038,3,1), Time.local(2038,2,29))
+    assert_equal(Time.local(2038,3,2), Time.local(2038,2,30))
+    assert_equal(Time.local(2038,3,3), Time.local(2038,2,31))
+    assert_equal(Time.local(2040,2,29), Time.local(2040,2,29))
+    assert_equal(Time.local(2040,3,1), Time.local(2040,2,30))
+    assert_equal(Time.local(2040,3,2), Time.local(2040,2,31))
+    n = 2 ** 64
+    n += 400 - n % 400 # n is over 2^64 and multiple of 400
+    assert_equal(Time.local(n,2,29),Time.local(n,2,29))
+    assert_equal(Time.local(n,3,1), Time.local(n,2,30))
+    assert_equal(Time.local(n,3,2), Time.local(n,2,31))
+    n += 100
+    assert_equal(Time.local(n,3,1), Time.local(n,2,29))
+    assert_equal(Time.local(n,3,2), Time.local(n,2,30))
+    assert_equal(Time.local(n,3,3), Time.local(n,2,31))
+    n += 4
+    assert_equal(Time.local(n,2,29),Time.local(n,2,29))
+    assert_equal(Time.local(n,3,1), Time.local(n,2,30))
+    assert_equal(Time.local(n,3,2), Time.local(n,2,31))
+    n += 1
+    assert_equal(Time.local(n,3,1), Time.local(n,2,29))
+    assert_equal(Time.local(n,3,2), Time.local(n,2,30))
+    assert_equal(Time.local(n,3,3), Time.local(n,2,31))
   end
 
   def test_future