use oxc_ast::ast::Program;
use oxc_ast_visit::Visit;
use oxc_semantic::Semantic;
use crate::rules::{Rule, RuleFinding, RuleMeta, Severity};
pub struct NoSideEffectsInRender;
const RULE_META: RuleMeta = RuleMeta {
id: "no-side-effects-in-render",
default_severity: Severity::Error,
category: "react",
description: "No side effects (subscriptions, mutations) during render",
};
impl Rule for NoSideEffectsInRender {
fn meta(&self) -> &RuleMeta {
&RULE_META
}
fn run(&self, program: &Program, _semantic: &Semantic, source_text: &str) -> Vec<RuleFinding> {
let mut collector = SideEffectCollector {
findings: Vec::new(),
source: source_text,
};
collector.visit_program(program);
collector.findings
}
}
struct SideEffectCollector<'a> {
findings: Vec<RuleFinding>,
source: &'a str,
}
impl<'a> Visit<'a> for SideEffectCollector<'a> {
fn visit_call_expression(&mut self, expr: &oxc_ast::ast::CallExpression<'a>) {
if let oxc_ast::ast::Expression::Identifier(ident) = &expr.callee {
match ident.name.as_str() {
"addEventListener"
| "removeEventListener"
| "subscribe"
| "unsubscribe"
| "setTimeout"
| "setInterval"
| "MutationObserver"
| "IntersectionObserver"
| "fetch"
| "XMLHttpRequest" => {
let start = expr.span.start as usize;
let line = self.source[..start].lines().count().max(1);
let col = start - self.source[..start].rfind('\n').map(|i| i + 1).unwrap_or(0);
self.findings.push(RuleFinding {
line,
column: col + 1,
message: format!(
"Potential side effect `{}()` in render — move to useEffect",
ident.name
),
});
}
_ => {}
}
}
}
}