All enum values not handled in switch cases. ( -Wswitch-enum )

[shamprasadps]

Bug Report

• What is the issue you have?
  I am having issues while compiling a C++ program using the json.hpp file. I am using the complier options -Wswitch-enum and -Werror. I see that all the enums are not handled in the switch cases, which is why I am seeing some errors while compiling.

• Please describe the steps to reproduce the issue. Can you provide a small but working code example?
  Include the json.hpp in the header of a c++ program and compile the program using -Wswitch-enum and -Werror options.

• What is the expected behavior?
  All enums must be handled and there should be no errors while using these compiler options.

• And what is the actual behavior instead?
  Actual behaviour: It throws the errors like "src/json.hpp:3005:9: error: enumeration value ‘end_array’ not handled in switch [-Werror=switch-enum]"

• Which compiler and operating system are you using? Is it a supported compiler?
  Im using a Ubuntu OS and using a supported compiler.

• Did you use a released version of the library or the version from the develop branch?
  Used from 'develop' branch.

• If you experience a compilation error: can you compile and run the unit tests?
  Not experiencing any issues with the existing compiler options. Errors only when using -Wswitch-enum and -Werror.

Feature Request

• Describe the feature in as much detail as possible.

• Include sample usage where appropriate.

[nlohmann]

Seems to be a duplicate of #555.

[shamprasadps]

Yes . It is a duplicate of this issue. I guess it was rejected because not all enums were handled in switch cases and it still reported some warnings. I have added the enums in the switch cases and a default label too.
I do agree that the changes made here to handle -Wswitch-enum for gcc , will throw warnings when clang++ is used with -Wcovered-switch-default option.

[nlohmann]

Right - we need to decide whether we want to make Clang or GCC happy, because now we would have

warning: default label in switch which covers all enumeration values [-Wcovered-switch-default]

all over the place.

[nlohmann]

I do not like the idea add redundancies to the code to make GCC happy while adding a Clang warning at the same time. See #555 for a discussion.