CSV#read consumes the same lines with other methods like CSV#shift

GitHub: fix GH-258

Reported by Lhoussaine Ghallou. Thanks!!!

Author: kou

lib/csv.rb

@@ -2586,7 +2586,14 @@ def each(&block)
   #   # Raises IOError (not opened for reading)
   #   csv.read
   def read
-    rows = to_a
+    rows = []
+    enumerator = parser_enumerator
+    begin
+      while true
+        rows << enumerator.next
+      end
+    rescue StopIteration
+    end
     if parser.use_headers?
       Table.new(rows, headers: parser.headers)
     else

test/csv/parse/test_read.rb

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# frozen_string_literal: false
+
+require_relative "../helper"
+
+class TestCSVParseRead < Test::Unit::TestCase
+  extend DifferentOFS
+
+  def test_shift
+    data = <<-CSV
+1
+2
+3
+    CSV
+    csv = CSV.new(data)
+    assert_equal([
+                   ["1"],
+                   [["2"], ["3"]],
+                   nil,
+                 ],
+                 [
+                   csv.shift,
+                   csv.read,
+                   csv.shift,
+                 ])
+  end
+end