Added skeleton evaluator tests for other chess pieces.
Added skeleton tests for rook and knight evaluators.
Beginning the process of splitting tests for various evaluators into different files (as they're very verbose).
Split evaluators into separate test files. Pawn evaluator tests are the only tests implemented thus far.
Slight docstring tweaks to bishop and rook evaluators to note that I'll be using them to evaluate the queen's moves. Implemented tests for ordinary knight movement.
Beginning to implement tests for knight blocked movement.
Finished adding blocked movement logic to knight evaluator.
Added skeleton tests for king evaluator.
Added movement and capturing logic tests for king evaluator.
Implemented move and capture tests for bishops and diagonally-moving queens.
Implemented tests for moving and capturing with rooks and horizontally-moving queens.
Fixed typo.
Added tests asserting that moving or capturing horizontally with a bishop fails.
Modified tests to refer to a specific piece using the rank and file (to preclude the possibility of an unintended piece being selected to make the move and yielding false results).
Added tests asserting that moving or capturing diagonally with a rook fails.
Added MoveAmbiguousError.
Altered exceptions raised by evaluators and evaluate_rank_and_file to more appropriate exceptions.
Added tests for _evaluate_rank_and_file.
Tests for _evaluate_rank_and_file are now passing.
Modified tests to assert that MoveNotLegal and MoveAmbiguous errors are raised at the appropriate times. Modified _evaluate_rank_and_file to raise these errors at the appropriate times.