Get rid of warnings from rspec-core's library and spec code.

Changelog.md

@@ -60,6 +60,7 @@ Bug fixes
   doc string has been provided (David Chelimsky).
 * Fix the memoized methods (`let` and `subject`) leaking `define_method`
   as a `public` method. (Thomas Holmes and Jon Rowe) (#873)
+* Silence warnings coming from the test suite. (Pete Higgins)
 
 Deprecations
 

lib/rspec/core/memoized_helpers.rb

@@ -139,6 +139,7 @@ def preserve_accessed_lets
 
           @example_group_instance.class.class_eval do
             hash.each do |key, value|
+              undef_method(key) if method_defined?(key)
               define_method(key) { value }
             end
           end

spec/rspec/core/example_group_spec.rb

@@ -906,7 +906,7 @@ def define_and_run_group(define_outer_example = false)
 
         it "sets RSpec.wants_to_quit flag if encountering an exception in before(:all)" do
           group.before(:all) { raise "error in before all" }
-          example = group.example("equality") { expect(1).to eq(2) }
+          group.example("equality") { expect(1).to eq(2) }
           expect(group.run).to be_false
           expect(RSpec.wants_to_quit).to be_true
         end

spec/rspec/core/example_spec.rb

@@ -8,7 +8,7 @@
   end
 
   let(:example_instance) do
-    example_group.example('example description')
+    example_group.example('example description') { }
   end
 
   it_behaves_like "metadata hash builder" do
@@ -28,7 +28,7 @@ def capture_stdout
   end
 
   it 'can be pretty printed' do
-    output = capture_stdout { pp example_instance }
+    output = ignoring_warnings { capture_stdout { pp example_instance } }
     expect(output).to include("RSpec::Core::Example")
   end
 

spec/rspec/core/formatters/base_text_formatter_spec.rb

@@ -55,7 +55,7 @@ def run_all_and_dump_failures
         exception_without_message = Exception.new()
         exception_without_message.stub(:message) { nil }
         group.example("example name") { raise exception_without_message }
-        expect { run_all_and_dump_failures }.not_to raise_error(NoMethodError)
+        expect { run_all_and_dump_failures }.not_to raise_error
       end
 
       it "preserves ancestry" do
@@ -70,7 +70,7 @@ def run_all_and_dump_failures
         gonzo_exception = RuntimeError.new
         gonzo_exception.stub(:message) { gonzo_exception }
         group.example("example name") { raise gonzo_exception }
-        expect { run_all_and_dump_failures }.not_to raise_error(NoMethodError)
+        expect { run_all_and_dump_failures }.not_to raise_error
       end
     end
 
@@ -218,7 +218,7 @@ def run_all_and_dump_pending
           exception_without_message = Exception.new()
           exception_without_message.stub(:message) { nil }
           group.example("example name") { pending { raise exception_without_message } }
-          expect { run_all_and_dump_pending }.not_to raise_error(NoMethodError)
+          expect { run_all_and_dump_pending }.not_to raise_error
         end
       end
 

spec/support/helper_methods.rb

@@ -3,9 +3,17 @@ def relative_path(path)
     RSpec::Core::Metadata.relative_path(path)
   end
 
+  def ignoring_warnings
+    original = $VERBOSE
+    $VERBOSE = nil
+    result = yield
+    $VERBOSE = original
+    result
+  end
+
   def safely
     Thread.new do
-      $SAFE = 3
+      ignoring_warnings { $SAFE = 3 }
       yield
     end.join