Inherit Roo::Excelx::Coordinate from Array

[chopraanmol1]

Profiling Script

MemoryProfiler.report{ Roo::Excelx.new(file_name).tap{|x|(2..x.last_row).each{|i| x.row(i)}} }.pretty_print

Master:

Total allocated: 34559100 bytes (504994 objects)
Total retained:  5563403 bytes (103022 objects)

allocated memory by gem
-----------------------------------
  19254338  roo/lib
   8509100  nokogiri-1.8.4
   6793822  rubyzip-1.2.2
      1304  tmpdir
       320  weakref
       216  other

allocated objects by gem
-----------------------------------
    358381  roo/lib
    145846  nokogiri-1.8.4
       735  rubyzip-1.2.2
        22  tmpdir
         8  weakref
         2  other

retained memory by gem
-----------------------------------
   5561094  roo/lib
       792  rubyzip-1.2.2
       725  nokogiri-1.8.4
       320  weakref
       296  tmpdir
       176  other

retained objects by gem
-----------------------------------
    102989  roo/lib
        14  nokogiri-1.8.4
         8  weakref
         7  rubyzip-1.2.2
         3  tmpdir
         1  other

After Patch:

Total allocated: 33439850 bytes (477013 objects)
Total retained:  4444153 bytes (75041 objects)

allocated memory by gem
-----------------------------------
  18135098  roo/lib
   8509100  nokogiri-1.8.4
   6793812  rubyzip-1.2.2
      1304  tmpdir
       320  weakref
       216  other

allocated objects by gem
-----------------------------------
    330400  roo/lib
    145846  nokogiri-1.8.4
       735  rubyzip-1.2.2
        22  tmpdir
         8  weakref
         2  other

retained memory by gem
-----------------------------------
   4441854  roo/lib
       782  rubyzip-1.2.2
       725  nokogiri-1.8.4
       320  weakref
       296  tmpdir
       176  other

retained objects by gem
-----------------------------------
     75008  roo/lib
        14  nokogiri-1.8.4
         8  weakref
         7  rubyzip-1.2.2
         3  tmpdir
         1  other

Summary

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Thanks for contributing to Roo!

[coveralls]

Coverage decreased (-0.01%) to 93.836% when pulling 00356c2 on chopraanmol1:inherit_coordinate_from_array into bfcfba4 on roo-rb:master.

[tgturner]

This looks good! Might be worth adding some basic test coverage for the Coordinate class and for extract_coordinates

[chopraanmol1]

@tgturner as per your suggestion I've added test coverage for extract_coordinate and Coordinate class