Improvement error message

[ppputtyo]

概要

• visitor/以下、validate.rsにおいて発生するエラーの表示をcargo風に変更しました。

例1 (ERRORノードが発生した場合)

input

select * from test from test from test

従来

Unexpected syntax error: visit_select_stmt: ERROR node appeared
Range { start_byte: 9, end_byte: 28, start_point: Point { row: 0, column: 9 }, end_point: Point { row: 0, column: 28 } }

変更後

Unexpected syntax error: visit_select_stmt: ERROR node appeared 
  |
1 | select * from test from test from test
  |          ^^^^^^^^^^^^^^^^^^^ Appears as "ERROR" node on the CST
  |

例2 (フォーマット前とフォーマット後のトークン数が違う場合)

input

seelect * from y

従来

Validation Error: different length. src=2, dst=1

変更後

Validation Error: different kind token: Errors have occurred near the following token
  |
1 | seelect * from y
  |         ^ After format: " (kind: source_file)"
  |

close #32

[tanzaku]

LGTM