rigsql_rules/layout/
lt12.rs

1use crate::rule::{CrawlType, Rule, RuleContext, RuleGroup};
2use crate::violation::{LintViolation, SourceEdit};
3
4/// LT12: Files must end with a single trailing newline.
5#[derive(Debug, Default)]
6pub struct RuleLT12;
7
8impl Rule for RuleLT12 {
9    fn code(&self) -> &'static str {
10        "LT12"
11    }
12    fn name(&self) -> &'static str {
13        "layout.end_of_file"
14    }
15    fn description(&self) -> &'static str {
16        "Files must end with a single trailing newline."
17    }
18    fn explanation(&self) -> &'static str {
19        "Files should end with exactly one newline character. Missing trailing newlines \
20         can cause issues with some tools, and multiple trailing newlines are untidy."
21    }
22    fn groups(&self) -> &[RuleGroup] {
23        &[RuleGroup::Layout]
24    }
25    fn is_fixable(&self) -> bool {
26        true
27    }
28
29    fn crawl_type(&self) -> CrawlType {
30        CrawlType::RootOnly
31    }
32
33    fn eval(&self, ctx: &RuleContext) -> Vec<LintViolation> {
34        let source = ctx.source;
35        if source.is_empty() {
36            return vec![];
37        }
38
39        let end = source.len() as u32;
40
41        if !source.ends_with('\n') {
42            return vec![LintViolation::with_fix(
43                self.code(),
44                "File does not end with a trailing newline.",
45                rigsql_core::Span::new(end, end),
46                vec![SourceEdit::insert(end, "\n")],
47            )];
48        }
49
50        // Check for multiple trailing newlines (handle both \n and \r\n)
51        let trimmed = source.trim_end_matches(&['\n', '\r'][..]);
52        let trailing_newlines = source[trimmed.len()..]
53            .bytes()
54            .filter(|&b| b == b'\n')
55            .count();
56        if trailing_newlines > 1 {
57            let span_start = trimmed.len() as u32;
58            return vec![LintViolation::with_fix(
59                self.code(),
60                format!(
61                    "File ends with {} trailing newlines instead of 1.",
62                    trailing_newlines
63                ),
64                rigsql_core::Span::new(span_start, end),
65                vec![SourceEdit::replace(
66                    rigsql_core::Span::new(span_start, end),
67                    "\n",
68                )],
69            )];
70        }
71
72        vec![]
73    }
74}
75
76#[cfg(test)]
77mod tests {
78    use super::*;
79    use crate::test_utils::lint_sql;
80
81    #[test]
82    fn test_lt12_flags_no_trailing_newline() {
83        let violations = lint_sql("SELECT 1", RuleLT12);
84        assert_eq!(violations.len(), 1);
85    }
86
87    #[test]
88    fn test_lt12_accepts_single_trailing_newline() {
89        let violations = lint_sql("SELECT 1\n", RuleLT12);
90        assert_eq!(violations.len(), 0);
91    }
92
93    #[test]
94    fn test_lt12_flags_multiple_trailing_newlines() {
95        let violations = lint_sql("SELECT 1\n\n", RuleLT12);
96        assert_eq!(violations.len(), 1);
97    }
98}
rigsql_rules/layout/lt12.rs

rigsql_rules/layout/
lt12.rs
