Failures:

  1) expect { ... }.to raise_error can supresses the warning when configured to do so
     Failure/Error: expect_no_warnings
     NameError:
       undefined local variable or method `expect_no_warnings' for #<RSpec::ExampleGroups::ExpectToRaiseError:0x007ff7795316c8>
     # ./spec/rspec/matchers/built_in/raise_error_spec.rb:18:in `block (2 levels) in <top (required)>'

  2) expect { ... }.to raise_error does not issue a warning when a block is passed
     Failure/Error: expect_no_warnings
     NameError:
       undefined local variable or method `expect_no_warnings' for #<RSpec::ExampleGroups::ExpectToRaiseError:0x007ff77953b8f8>
     # ./spec/rspec/matchers/built_in/raise_error_spec.rb:33:in `block (2 levels) in <top (required)>'

  3) expect { ... }.to raise_error does not issue a warning when an exception class is specified (even if it is just `Exception`)
     Failure/Error: expect_no_warnings
     NameError:
       undefined local variable or method `expect_no_warnings' for #<RSpec::ExampleGroups::ExpectToRaiseError:0x007ff77953a638>
     # ./spec/rspec/matchers/built_in/raise_error_spec.rb:23:in `block (2 levels) in <top (required)>'

  4) expect { ... }.to raise_error does not issue a warning when a message is specified
     Failure/Error: expect_no_warnings
     NameError:
       undefined local variable or method `expect_no_warnings' for #<RSpec::ExampleGroups::ExpectToRaiseError:0x007ff779538090>
     # ./spec/rspec/matchers/built_in/raise_error_spec.rb:28:in `block (2 levels) in <top (required)>'

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1972 examples, 4 failures