feat: adds the one_empty_line lint warning

[simojoe]

This pull request adds a new rule to wdl.

• Rule Name: one_empty_line
• Rule Kind: Lint warning
• Rule Code: v1::W011
• Packages: wdl-grammar

Parses the file line by line, trims whitespace and emits one warning per block of 2 or more continuous empty lines.

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Rule specific checks:

• You have added the rule as an entry within the the package-specific rule
  tables (wdl-ast/src/v1.rs for AST-based rules and
  wdl-grammar/src/v1.rs for parse tree-based rules).
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    wdl-ast/src/v1/validation.rs.
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  • Validation rules added to wdl-grammar should be added to fn rules() within
    wdl-grammar/src/v1/validation.rs.
  • Lint rules added to wdl-grammar should be added to fn rules() within
    wdl-grammar/src/v1/lint.rs.
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  added/removed are now reflected in the baseline configuration file
  (Gauntlet.toml).

[a-frantz]

Looks good to me aside from what @adthrasher pointed out. I have the same question, but once that's resolved I give the all clear

[simojoe]

Good point! Modify to actually tag the last infringing line. Since this warning requires as least two lines to report, this should always unwrap successfully.

[adthrasher]

@a-frantz - This now reports the last problematic blank line. Do you think that is sufficient or should it flag every extra blank line?

I was thinking something like this, so that every empty line would be flagged.

        for (line_no, start_byte_no, _end_byte_no, line) in tree.as_str().lines_with_offsets() {
            if line.trim().is_empty() {
                if n_empty_lines >= 1 {
                    warnings.push_back(self.more_than_one_empty_line(Location::Position(
                        Position::new(
                            NonZeroUsize::try_from(line_no.get()).unwrap(),
                            NonZeroUsize::try_from(1).unwrap(),
                            start_byte_no,
                         ),
                     )));
                }
                n_empty_lines += 1;
            }  else {
                n_empty_lines = 0;
            }
        }

[simojoe]

I would be happy modifying my PR as to fit the expectations.

The one lint warning per block of erroneous empty lines design choice was defined in the original post as it was not previously defined in the description.

The EOF check was not part of the PR?

[adthrasher]

I would be happy modifying my PR as to fit the expectations.

The one lint warning per block of erroneous empty lines design choice was defined in the original post as it was not previously defined in the description.

The EOF check was not part of the PR?

I made a change to report a Span so that the entire set of extraneous whitespace is reported.

As for the EOF, @a-frantz and I discussed it afterward and he pointed out your other PR for newline_eof. I had simply forgotten that was a separate rule.

Thanks for your contributions, @simojoe!