From 4e488d20a08b565fe4a4ec740c4e13ff705fdd9e Mon Sep 17 00:00:00 2001
From: Daniel Pfister <80419299+0x2a-42@users.noreply.github.com>
Date: Tue, 31 Dec 2024 14:59:48 +0100
Subject: [PATCH] Add warning for empty rule
---
src/frontend/diag.rs | 9 +++++++++
src/frontend/sema.rs | 7 +++++--
2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/src/frontend/diag.rs b/src/frontend/diag.rs
index bc821f0..0bb46a0 100644
--- a/src/frontend/diag.rs
+++ b/src/frontend/diag.rs
@@ -34,6 +34,7 @@ pub const UNUSED_RULE: &str = "W001";
pub const UNUSED_TOKEN: &str = "W002";
pub const UNUSED_OPEN_NODE: &str = "W003";
pub const REDUNDANT_ELISION: &str = "W004";
+pub const EMPTY_RULE: &str = "W005";
pub trait LanguageErrors {
fn invalid_binding_pos(span: &Span) -> Self;
@@ -67,6 +68,7 @@ pub trait LanguageErrors {
fn redundant_elision(span: &Span) -> Self;
fn expected_rule(span: &Span) -> Self;
fn missing_node_name(span: &Span) -> Self;
+ fn empty_rule(span: &Span) -> Self;
}
impl LanguageErrors for Diagnostic {
@@ -359,4 +361,11 @@ impl LanguageErrors for Diagnostic {
.with_message("missing node name")
.with_labels(vec![Label::primary((), span.clone())])
}
+
+ fn empty_rule(span: &Span) -> Self {
+ Diagnostic::warning()
+ .with_code(EMPTY_RULE)
+ .with_message("empty rule")
+ .with_labels(vec![Label::primary((), span.clone())])
+ }
}
diff --git a/src/frontend/sema.rs b/src/frontend/sema.rs
index 0c9b4c0..bbd6981 100644
--- a/src/frontend/sema.rs
+++ b/src/frontend/sema.rs
@@ -258,8 +258,11 @@ impl<'a> GeneralCheck<'a> {
diags: &mut Vec<Diagnostic>,
sema: &mut SemanticData<'a>,
) {
- rule.regex(cst)
- .map(|regex| self.check_regex(cst, rule, regex, diags, sema, false, false));
+ if let Some(regex) = rule.regex(cst) {
+ self.check_regex(cst, rule, regex, diags, sema, false, false);
+ } else {
+ diags.push(Diagnostic::empty_rule(&rule.span(cst)));
+ }
self.check_recursive(cst, sema, rule, diags);
if let Some(regex) = rule.regex(cst) {
let mut open = HashSet::new();