Rescue truly all exceptions

Author: mtsmfm

CHANGELOG.md

@@ -10,6 +10,7 @@
 
 * Your contribution here.
 * [#1737](https://github.com/ruby-grape/grape/pull/1737): Fix translating error when passing symbols as params in custom validations - [@mlzhuyi](https://github.com/mlzhuyi).
+* []: Rescue truly all exceptions - [@mtsmfm](https://github.com/mtsmfm).
 
 ### 1.0.2 (1/10/2018)
 

README.md

@@ -2071,7 +2071,7 @@ literally accepts every request.
 
 ## Exception Handling
 
-Grape can be told to rescue all `StandardError` exceptions and return them in the API format.
+Grape can be told to rescue all exceptions and return them in the API format.
 
 ```ruby
 class Twitter::API < Grape::API
@@ -2098,7 +2098,7 @@ class Twitter::API < Grape::API
 end
 ```
 
-In this case ```UserDefinedError``` must be inherited from ```StandardError```.
+```UserDefinedError``` can be inherited from any exception class.
 
 Notice that you could combine these two approaches (rescuing custom errors takes precedence). For example, it's useful for handling all exceptions except Grape validation errors.
 

lib/grape/middleware/error.rb

@@ -36,7 +36,7 @@ def call!(env)
           error_response(catch(:error) do
             return @app.call(@env)
           end)
-        rescue StandardError => e
+        rescue Exception => e # rubocop:disable Lint/RescueException
           is_rescuable = rescuable?(e.class)
           if e.is_a?(Grape::Exceptions::Base) && (!is_rescuable || rescuable_by_grape?(e.class))
             handler = ->(arg) { error_response(arg) }

spec/grape/middleware/exception_spec.rb

@@ -103,8 +103,13 @@ def app
           run ExceptionSpec::OtherExceptionApp
         end
       end
-      it 'does not trap errors other than StandardError' do
-        expect { get '/' }.to raise_error(NotImplementedError, 'snow!')
+      it 'sets the message appropriately' do
+        get '/'
+        expect(last_response.body).to eq('snow!')
+      end
+      it 'defaults to a 500 status' do
+        get '/'
+        expect(last_response.status).to eq(500)
       end
     end
   end