rigsql_rules/layout/
lt11.rs

1use rigsql_core::{Segment, SegmentType, TokenSegment};
2
3use crate::rule::{CrawlType, Rule, RuleContext, RuleGroup};
4use crate::violation::LintViolation;
5
6/// LT11: Set operators (UNION, INTERSECT, EXCEPT) should be surrounded by newlines.
7///
8/// Set operators should have a newline before and after them for readability.
9#[derive(Debug, Default)]
10pub struct RuleLT11;
11
12impl Rule for RuleLT11 {
13    fn code(&self) -> &'static str {
14        "LT11"
15    }
16    fn name(&self) -> &'static str {
17        "layout.set_operators"
18    }
19    fn description(&self) -> &'static str {
20        "Set operators should be surrounded by newlines."
21    }
22    fn explanation(&self) -> &'static str {
23        "Set operators such as UNION, INTERSECT, and EXCEPT combine the results of \
24         multiple queries. They should be surrounded by newlines to visually separate \
25         the individual queries and improve readability."
26    }
27    fn groups(&self) -> &[RuleGroup] {
28        &[RuleGroup::Layout]
29    }
30    fn is_fixable(&self) -> bool {
31        false
32    }
33
34    fn crawl_type(&self) -> CrawlType {
35        CrawlType::RootOnly
36    }
37
38    fn eval(&self, ctx: &RuleContext) -> Vec<LintViolation> {
39        let mut violations = Vec::new();
40        let tokens = collect_leaf_tokens(ctx.segment);
41
42        for (i, t) in tokens.iter().enumerate() {
43            if !t.token.text.eq_ignore_ascii_case("UNION")
44                && !t.token.text.eq_ignore_ascii_case("INTERSECT")
45                && !t.token.text.eq_ignore_ascii_case("EXCEPT")
46            {
47                continue;
48            }
49
50            let op_span = t.token.span;
51
52            let has_newline_before = check_adjacent_newline(&tokens, i, Direction::Before);
53
54            // Determine end of set operator (skip ALL if present)
55            let mut end_idx = i;
56            let mut j = i + 1;
57            while j < tokens.len() {
58                if tokens[j].segment_type.is_trivia() {
59                    j += 1;
60                } else {
61                    if tokens[j].token.text.eq_ignore_ascii_case("ALL") {
62                        end_idx = j;
63                    }
64                    break;
65                }
66            }
67
68            let has_newline_after = check_adjacent_newline(&tokens, end_idx, Direction::After);
69
70            if !has_newline_before {
71                let operator_text = t.token.text.to_ascii_uppercase();
72                violations.push(LintViolation::with_msg_key(
73                    self.code(),
74                    format!("Expected newline before '{}'.", operator_text),
75                    op_span,
76                    "rules.LT11.msg.before",
77                    vec![("operator".to_string(), operator_text)],
78                ));
79            }
80
81            if !has_newline_after {
82                let operator_text = t.token.text.to_ascii_uppercase();
83                violations.push(LintViolation::with_msg_key(
84                    self.code(),
85                    format!("Expected newline after '{}'.", operator_text),
86                    op_span,
87                    "rules.LT11.msg.after",
88                    vec![("operator".to_string(), operator_text)],
89                ));
90            }
91        }
92
93        violations
94    }
95}
96
97enum Direction {
98    Before,
99    After,
100}
101
102fn check_adjacent_newline(tokens: &[TokenSegment], idx: usize, dir: Direction) -> bool {
103    let mut j = match dir {
104        Direction::Before => idx.wrapping_sub(1),
105        Direction::After => idx + 1,
106    };
107    loop {
108        if j >= tokens.len() {
109            return false;
110        }
111        if tokens[j].segment_type == SegmentType::Newline {
112            return true;
113        }
114        // Skip whitespace and comments (e.g., `UNION -- noqa: AM02\n` should be OK)
115        if tokens[j].segment_type != SegmentType::Whitespace
116            && tokens[j].segment_type != SegmentType::LineComment
117            && tokens[j].segment_type != SegmentType::BlockComment
118        {
119            return false;
120        }
121        j = match dir {
122            Direction::Before => j.wrapping_sub(1),
123            Direction::After => j + 1,
124        };
125    }
126}
127
128/// Collect all leaf TokenSegments by cloning (cheap: Token contains SmolStr).
129fn collect_leaf_tokens(segment: &Segment) -> Vec<TokenSegment> {
130    let mut out = Vec::new();
131    collect_leaf_tokens_inner(segment, &mut out);
132    out
133}
134
135fn collect_leaf_tokens_inner(segment: &Segment, out: &mut Vec<TokenSegment>) {
136    match segment {
137        Segment::Token(t) => out.push(t.clone()),
138        Segment::Node(n) => {
139            for child in &n.children {
140                collect_leaf_tokens_inner(child, out);
141            }
142        }
143    }
144}
145
146#[cfg(test)]
147mod tests {
148    use super::*;
149    use crate::test_utils::lint_sql;
150
151    #[test]
152    fn test_lt11_flags_inline_union() {
153        let violations = lint_sql("SELECT 1 UNION SELECT 2", RuleLT11);
154        assert!(!violations.is_empty());
155        assert!(violations.iter().all(|v| v.rule_code == "LT11"));
156    }
157
158    #[test]
159    fn test_lt11_accepts_newlines() {
160        let violations = lint_sql("SELECT 1\nUNION\nSELECT 2", RuleLT11);
161        assert_eq!(violations.len(), 0);
162    }
163
164    #[test]
165    fn test_lt11_accepts_union_with_trailing_comment() {
166        // UNION followed by a line comment and then a newline should be OK
167        let violations = lint_sql("SELECT 1\nUNION -- noqa: AM02\nSELECT 2", RuleLT11);
168        assert_eq!(violations.len(), 0);
169    }
170
171    #[test]
172    fn test_lt11_accepts_union_with_leading_comment() {
173        // Comment before UNION on a separate line
174        let violations = lint_sql("SELECT 1\n-- comment\nUNION\nSELECT 2", RuleLT11);
175        assert_eq!(violations.len(), 0);
176    }
177}
rigsql_rules/layout/lt11.rs

rigsql_rules/layout/
lt11.rs
