//! `enum-value-collision` lint rule.
use std::collections::HashSet;
use crate::ir::user_type::UserTypeKind;
use crate::lint::finding::Finding;
use crate::lint::source_tree::SourceTree;
/// `enum-value-collision` — fires when an enum type has duplicate value labels.
///
/// The source parser rejects duplicates at parse time, so this is a
/// defense-in-depth check for catalogs constructed programmatically.
pub fn check(tree: &SourceTree) -> Vec<Finding> {
let mut out = Vec::new();
for ty in &tree.catalog.types {
if let UserTypeKind::Enum { values } = &ty.kind {
let mut seen: HashSet<&str> = HashSet::new();
for v in values {
if !seen.insert(v.name.as_str()) {
out.push(Finding::error(
"enum-value-collision",
format!(
"enum `{q}` has duplicate value `{label}`",
q = ty.qname,
label = v.name,
),
));
}
}
}
}
out
}