1 files changed, 35 insertions, 0 deletions
diff --git a/test/logger/test_formatter.rb b/test/logger/test_formatter.rb
new file mode 100644
index 0000000000..9465722991
--- /dev/null
+++ b/test/logger/test_formatter.rb
@@ -0,0 +1,35 @@
+# coding: US-ASCII
+# frozen_string_literal: false
+require 'logger'
+
+class TestFormatter < Test::Unit::TestCase
+  def test_call
+    severity = 'INFO'
+    time = Time.now
+    progname = 'ruby'
+    msg = 'This is a test'
+    formatter = Logger::Formatter.new
+
+    result = formatter.call(severity, time, progname, msg)
+    time_matcher = /\d{4}\-\d{2}\-\d{2}T\d{2}:\d{2}:\d{2}\.\d{6}/
+    matcher = /#{severity[0..0]}, \[#{time_matcher} #\d+\]  #{severity} -- #{progname}: #{msg}\n/
+
+    assert_match(matcher, result)
+  end
+
+  class CustomFormatter < Logger::Formatter
+    def call(time)
+      format_datetime(time)
+    end
+  end
+
+  def test_format_datetime
+    time = Time.now
+    formatter = CustomFormatter.new
+
+    result = formatter.call(time)
+    matcher = /^\d{4}\-\d{2}\-\d{2}T\d{2}:\d{2}:\d{2}\.\d{6}$/
+
+    assert_match(matcher, result)
+  end
+end