Suppress warnings except for when last evaluation

Co-authored-by: Kazuhiro NISHIYAMA <zn@mbf.nifty.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/irb/color.rb b/lib/irb/color.rb
index 3ce628ff24..d2b9674a71 100644
--- a/lib/irb/color.rb
+++ b/lib/irb/color.rb
@@ -154,6 +154,7 @@ module IRB # :nodoc:
       def scan(code, allow_last_error:)
         pos = [1, 0]
 
+        verbose, $VERBOSE = $VERBOSE, nil
         lexer = Ripper::Lexer.new(code)
         if lexer.respond_to?(:scan) # Ruby 2.7+
           lexer.scan.each do |elem|
@@ -177,6 +178,7 @@ module IRB # :nodoc:
             yield(elem.event, elem.tok, elem.state)
           end
         end
+        $VERBOSE = verbose
       end
 
       def dispatch_seq(token, expr, str, in_symbol:)