From d27fa87418bcec8fff909f75a547a7c5e6dc83e5 Mon Sep 17 00:00:00 2001
From: aycabta <aycabta@gmail.com>
Date: Sat, 25 Apr 2020 01:45:03 +0900
Subject: [PATCH] [ruby/reline] New items to history are dropped if
 history_size is zero

https://github.com/ruby/reline/commit/9bdbed9cbc
---
 lib/reline/history.rb       |  4 ++++
 test/reline/test_history.rb | 10 ++++++++++
 2 files changed, 14 insertions(+)

diff --git a/lib/reline/history.rb b/lib/reline/history.rb
index d95f1cebc3..2e6a12ecf3 100644
--- a/lib/reline/history.rb
+++ b/lib/reline/history.rb
@@ -29,6 +29,8 @@ class Reline::History < Array
   end
 
   def push(*val)
+    # If history_size is zero, all histories are dropped.
+    return self if @config.history_size.zero?
     diff = size + val.size - @config.history_size
     if diff > 0
       if diff <= size
@@ -43,6 +45,8 @@ class Reline::History < Array
   end
 
   def <<(val)
+    # If history_size is zero, all histories are dropped.
+    return self if @config.history_size.zero?
     shift if size + 1 > @config.history_size
     super(String.new(val, encoding: Reline.encoding_system_needs))
   end
diff --git a/test/reline/test_history.rb b/test/reline/test_history.rb
index 189f2db86d..0cb148d112 100644
--- a/test/reline/test_history.rb
+++ b/test/reline/test_history.rb
@@ -242,6 +242,16 @@ class Reline::History::Test < Reline::TestCase
     end
   end
 
+  def test_history_size_zero
+    history = history_new(history_size: 0)
+    assert_equal 0, history.size
+    history << 'aa'
+    history << 'bb'
+    assert_equal 0, history.size
+    history.push(*%w{aa bb cc})
+    assert_equal 0, history.size
+  end
+
   private
 
   def history_new(history_size: 10)