Replaced the tests of Binary Trees that need manual string matching

[rsriramc]

References to other Issues or PRs or Relevant literature

Closes #294

Brief description of what is fixed or changed

Replaced the testing techniques of Binary Trees where initially a manual string has to be fed; to the check of In-order and Pre-order traversals.

Other comments

Since a unique tree exists with a set of In-order and Pre-order traversals, this check is comparatively easy to use as there is no need of feeding a string of the nodes, instead of which two sets of keys of nodes are fed.

[codecov]

Codecov Report

Merging #304 (7da53d1) into master (3f3faad) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master      #304   +/-   ##
=========================================
  Coverage   98.866%   98.866%           
=========================================
  Files           25        25           
  Lines         2999      2999           
=========================================
  Hits          2965      2965           
  Misses          34        34           

[czgdp1807]

Seems good. Will merge tomorrow.

[czgdp1807]

There is this function which isn't tested. May be the tests for only this method can be kept along side the new tests.

[rsriramc]

There is this function which isn't tested. May be the tests for only this method can be kept along side the new tests.

There since I have replaced all the tests of the binary trees ,and all its derivatives. The __str__ method is not at all used in the tests except in one position which is here

But here comes two issues that the __str__ method is redefined in the Cartesian tree, which is not at all called in the test_binary_tree.

So code coverage has been reduced.

[rsriramc]

Shall I add explicit tests for the __str__ for both the basic binary tree and the redefined __str__ in the Cartesian tree; and add a commit to this?

[czgdp1807]

Yes. Sure

[rsriramc]

I have added the tests for the __str__ methods