react_auditor/rules/quality/
max_params.rs

1use oxc_ast::ast::Program;
2use oxc_ast_visit::Visit;
3use oxc_ast_visit::walk::walk_formal_parameters;
4use oxc_semantic::Semantic;
5
6use crate::rules::{Rule, RuleFinding, RuleMeta, Severity};
7
8pub struct MaxParams;
9
10const RULE_META: RuleMeta = RuleMeta {
11    id: "max-params",
12    default_severity: Severity::Warning,
13    category: "quality",
14    description: "Functions should have at most 3 parameters",
15};
16
17impl Rule for MaxParams {
18    fn meta(&self) -> &RuleMeta {
19        &RULE_META
20    }
21
22    fn run(&self, program: &Program, _semantic: &Semantic, source_text: &str) -> Vec<RuleFinding> {
23        let mut collector = ParamCollector {
24            findings: Vec::new(),
25            source: source_text,
26        };
27        collector.visit_program(program);
28        collector.findings
29    }
30}
31
32struct ParamCollector<'a> {
33    findings: Vec<RuleFinding>,
34    source: &'a str,
35}
36
37impl<'a> Visit<'a> for ParamCollector<'a> {
38    fn visit_formal_parameters(&mut self, params: &oxc_ast::ast::FormalParameters<'a>) {
39        if params.items.len() > 3 {
40            let start = params.span.start as usize;
41            let line = self.source[..start].lines().count().max(1);
42            let col = start - self.source[..start].rfind('\n').map(|i| i + 1).unwrap_or(0);
43
44            self.findings.push(RuleFinding {
45                line,
46                column: col + 1,
47                message: format!(
48                    "Function has {} parameters, max allowed is 3",
49                    params.items.len()
50                ),
51            });
52        }
53        walk_formal_parameters(self, params);
54    }
55}
react_auditor/rules/quality/max_params.rs

react_auditor/rules/quality/
max_params.rs
