Using Python 3.5+ os.scandir() optimized variant.
Starting.
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*Collecting tree differences
comparing [/home/name/Desktop/mergeall-3.0-beta/test/test1] [/home/name/Desktop/mergeall-3.0-beta/test/test2]
excluding /home/name/Desktop/mergeall-3.0-beta/test/test2/__bkp__
comparing [/home/name/Desktop/mergeall-3.0-beta/test/test1/d3] [/home/name/Desktop/mergeall-3.0-beta/test/test2/d3]
Phase runtime: 0.0003553049999709401
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*Reporting tree differences
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SAMEFILE DIFFERENCES: (name, dirfrom, dirto, why)
**These items will be replaced in dirto by automatic resolution**

[('f3.txt',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2',
  'modtime'),
 ('f6.txt',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2',
  'filesize'),
 ('f3.txt',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1/d3',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2/d3',
  'modtime'),
 ('.htaccess',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1/d3',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2/d3',
  'modtime')]
-------------------------------------------------------------------------------
UNIQUE ITEMS IN DIRTO: (names, dirfrom, dirto)
**These items will be deleted from dirto by automatic resolution**

[(['Desktop.ini', 'f2.txt', '$RECYCLE.BIN', '.Trash-1000', 'd2'],
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2'),
 (['desktop.ini', 'f5.txt', 'Thumbs.db'],
  '/home/name/Desktop/mergeall-3.0-beta/test/test1/d3',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2/d3')]
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UNIQUE ITEMS IN DIRFROM: (names, dirfrom, dirto)
**These items will be copied over to dirto by automatic resolution**

[(['f1.txt', 'd1', '.DS_Store', '._.TemporaryItems'],
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2'),
 (['.Trashes', 'f4.txt', '.DS_Store', '.fseventsd'],
  '/home/name/Desktop/mergeall-3.0-beta/test/test1/d3',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2/d3')]
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MIXED MODE NAMES: (name, dirfrom, dirto)
**These items will be replaced in dirto by automatic resolution**

[('m2',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2'),
 ('m1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test1',
  '/home/name/Desktop/mergeall-3.0-beta/test/test2')]
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*Summary
Compared    => files: 6, folders: 2
Differences => samefile: 4, uniqueto: 8, uniquefrom: 8, mixedmode: 2
Changed:
files   => created: 0, deleted: 0, replaced: 0
folders => created: 0, deleted: 0, replaced: 0
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Finished.