Enable and fix new cops

.rubocop.yml

@@ -43,11 +43,17 @@ Layout/SpaceAroundMethodCallOperator:
   Description: Checks method call operators to not have spaces around them.
   Enabled: true
 
+Layout/SpaceBeforeBrackets:
+  Enabled: true
+
 Layout/SpaceInsideHashLiteralBraces:
   Description: Use spaces inside hash literal braces - or don't.
   StyleGuide: https://github.com/rubocop-hq/ruby-style-guide#spaces-operators
   EnforcedStyle: no_space
 
+Lint/AmbiguousAssignment:
+  Enabled: true
+
 Lint/AmbiguousRegexpLiteral:
   Description: Checks for ambiguous regexp literals in the first argument of a method invocation without parentheses.
   Exclude:
@@ -66,12 +72,24 @@ Lint/DeprecatedOpenSSLConstant:
   Description: Don't use algorithm constants for `OpenSSL::Cipher` and `OpenSSL::Digest`.
   Enabled: true
 
+Lint/DuplicateBranch:
+  Enabled: true
+
 Lint/DuplicateElsifCondition:
   Enabled: true
 
+Lint/DuplicateRegexpCharacterClassElement:
+  Enabled: true
+
 Lint/DuplicateRescueException:
   Enabled: true
 
+Lint/EmptyBlock:
+  Enabled: true
+
+Lint/EmptyClass:
+  Enabled: true
+
 Lint/EmptyConditionalBody:
   Enabled: true
 
@@ -85,6 +103,9 @@ Lint/MixedRegexpCaptureTypes:
   Description: Do not mix named captures and numbered captures in a Regexp literal.
   Enabled: true
 
+Lint/NoReturnInBeginEndBlocks:
+  Enabled: true
+
 Lint/OutOfRangeRegexpRef:
   Enabled: true
 
@@ -99,9 +120,18 @@ Lint/StructNewOverride:
   Description: Disallow overriding the `Struct` built-in methods via `Struct.new`.
   Enabled: true
 
+Lint/ToEnumArguments:
+  Enabled: true
+
 Lint/TopLevelReturnWithArgument:
   Enabled: true
 
+Lint/UnexpectedBlockArity:
+  Enabled: true
+
+Lint/UnmodifiedReduceAccumulator:
+  Enabled: true
+
 Lint/UnreachableLoop:
   Enabled: true
 
@@ -147,6 +177,9 @@ Naming/FileName:
 Style/AccessorGrouping:
   Enabled: true
 
+Style/ArgumentsForwarding:
+  Enabled: true
+
 Style/ArrayCoercion:
   Enabled: true
 
@@ -156,6 +189,9 @@ Style/BisectedAttrAccessor:
 Style/CaseLikeIf:
   Enabled: true
 
+Style/CollectionCompact:
+  Enabled: true
+
 Style/CollectionMethods:
   Description: Enforces the use of consistent method names from the Enumerable module.
   PreferredMethods:
@@ -173,6 +209,9 @@ Style/DoubleNegation:
   StyleGuide: https://github.com/rubocop-hq/ruby-style-guide#no-bang-bang
   Enabled: false
 
+Style/DocumentDynamicEvalDefinition:
+  Enabled: true
+
 Style/ExplicitBlockArgument:
   # capturing as a proc has a performance hit, so is a case by case choice
   Enabled: false
@@ -204,6 +243,9 @@ Style/HashEachMethods:
   Description: Use Hash#each_key and Hash#each_value.
   Enabled: true
 
+Style/HashExcept:
+  Enabled: true
+
 Style/HashLikeCase:
   Enabled: true
 
@@ -219,9 +261,18 @@ Style/HashSyntax:
   Description: Checks hash literal syntax.
   EnforcedStyle: ruby19
 
+Style/NegatedIfElseCondition:
+  Enabled: true
+
+Style/NilLambda:
+  Enabled: true
+
 Style/OptionalBooleanParameter:
   Enabled: true
 
+Style/RedundantArgument:
+  Enabled: true
+
 Style/RedundantAssignment:
   Enabled: true
 
@@ -265,6 +316,9 @@ Style/StringLiterals:
   Description: Allow double-quoted strings without interpolation.
   EnforcedStyle: double_quotes
 
+Style/SwapValues:
+  Enabled: true
+
 Style/TrailingCommaInArrayLiteral:
   EnforcedStyleForMultiline: no_comma
 

lib/simplecov/configuration.rb

@@ -191,7 +191,7 @@ def configure(&block)
     #     end
     #
     def at_exit(&block)
-      return proc {} unless running || block_given?
+      return Proc.new unless running || block_given?
 
       @at_exit = block if block_given?
       @at_exit ||= proc { SimpleCov.result.format! }

spec/result_merger_spec.rb

@@ -233,6 +233,7 @@
         Timeout.timeout(1) do
           SimpleCov::ResultMerger.synchronize_resultset do
             SimpleCov::ResultMerger.synchronize_resultset do
+              # nothing
             end
           end
         end