[Fix #6675] Avoid printing deprecation warnings about constants

CHANGELOG.md

@@ -29,6 +29,7 @@
 * [#6806](https://github.com/rubocop-hq/rubocop/pull/6806): Remove `powerpack` dependency. ([@dduugg][])
 * [#6810](https://github.com/rubocop-hq/rubocop/pull/6810): Exclude gemspec file by default for `Metrics/BlockLength` cop. ([@koic][])
 * [#6813](https://github.com/rubocop-hq/rubocop/pull/6813): Allow unicode/display_width dependency version 1.5.0. ([@tagliala][])
+* [#6675](https://github.com/rubocop-hq/rubocop/issues/6675): Avoid printing deprecation warnings about constants. ([@elmasantos][])
 
 ## 0.65.0 (2019-02-19)
 
@@ -3855,3 +3856,4 @@
 [@enkessler]: https://github.com/enkessler
 [@tagliala]: https://github.com/tagliala
 [@unasuke]: https://github.com/unasuke
+[@elmasantos]: https://github.com/elmasantos

lib/rubocop/cop/lint/shadowed_exception.rb

@@ -107,12 +107,25 @@ def system_call_err?(error)
           error && error.ancestors[1] == SystemCallError
         end
 
+        def silence_warnings
+          # Replaces Kernel::silence_warnings since it hides any warnings,
+          # including the RuboCop ones
+          old_verbose = $VERBOSE
+          $VERBOSE = nil
+          yield
+        ensure
+          $VERBOSE = old_verbose
+        end
+
         def evaluate_exceptions(rescue_group)
           if rescue_group
             rescued_exceptions = rescued_exceptions(rescue_group)
             rescued_exceptions.each_with_object([]) do |exception, converted|
               begin
-                converted << Kernel.const_get(exception)
+                silence_warnings do
+                  # Avoid printing deprecation warnings about constants
+                  converted << Kernel.const_get(exception)
+                end
               rescue NameError
                 converted << nil
               end

spec/rubocop/cop/lint/shadowed_exception_spec.rb

@@ -30,6 +30,18 @@
       RUBY
     end
 
+    it 'rescue a exception without causing constant name deprecation warning' do
+      expect do
+        inspect_source(<<-RUBY.strip_indent)
+          def foo
+            something
+          rescue TimeoutError
+            handle_exception
+          end
+        RUBY
+      end.not_to output(/.*TimeoutError is deprecated/).to_stderr
+    end
+
     it 'accepts rescuing a single custom exception' do
       expect_no_offenses(<<-RUBY.strip_indent)
         begin