Remove test cases that vary based on codec for extendeddatacrossword_test.go

Context

The tests in extendeddatacrossword_test.go contain test cases for multiple codecs but after #151 this repo only supports one codec.

Example:

rsmt2d/extendeddatacrossword_test.go

Lines 24 to 31 in e8e042f

    
           tests := []struct { 
        
           	name string 
        
           	// Size of each share, in bytes 
        
           	shareSize int 
        
           	codec     Codec 
        
           }{ 
        
           	{"leopard", bufferSize, NewLeoRSCodec()}, 
        
           }

Proposal

Refactor the tests in this file to remove test cases that differ based on codec. This will likely remove a level of indentation from the interesting parts of this file.

Thanks for opening this issue!
Is there a long-term plan to exclusively use one codec? If so, it may be beneficial to refactor functions that currently accept a codec as an input parameter. These parameters would become redundant with only one supported codec. Alternatively, if multiple codecs will continue to be supported, it's useful to maintain the current structure of the tests. These tests comprehensively account for all input parameters of the function they aim to test, including the codec. (it is conceivable that if other codecs get added we need to re-deploy the same test structure as we currently have, resulting in redundant work). WDYT? @rootulp

I don't see any GH issues in this repo for adding new codecs. I think the current test structure is a byproduct of development (i.e. historically multiple codecs were supported) so IMO we should refactor to just support one codec.

If we need to add a new codec in the future, the PR that adds a new codec can (and should) add test coverage for the new codec.

	tests := []struct {
	name string
	// Size of each share, in bytes
	shareSize int
	codec Codec
	}{
	{"leopard", bufferSize, NewLeoRSCodec()},
	}