From 7a54789dd277315819f0c064cfb1ff76baa80b02 Mon Sep 17 00:00:00 2001
From: alexion <contact@alexion.dev>
Date: Sat, 26 Sep 2026 20:02:19 -0400
Subject: [PATCH] feat(xatu): identify ordered bindings

---
 src/xatu/rules.rs           | 18 ++++++++++++++----
 src/xatu/rules/let_order.rs | 12 ++++++++++--
 src/xatu/scope_graph.rs     |  2 ++
 src/xatu/xatu.rs            | 11 ++++++-----
 4 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/xatu/rules.rs b/src/xatu/rules.rs
index 589f580..558e302 100644
--- a/src/xatu/rules.rs
+++ b/src/xatu/rules.rs
@@ -21,15 +21,22 @@ pub struct Finding {
     pub rule_id: &'static str,
     pub range: ast::SourceRange,
     pub message: &'static str,
+    pub binding: Option<String>,
 }
 
 impl std::fmt::Display for Diagnostic {
     fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         write!(
             formatter,
-            "{}: {}",
+            "[{}] {}",
             self.finding.rule_id, self.finding.message
-        )
+        )?;
+
+        if let Some(binding) = &self.finding.binding {
+            write!(formatter, ": {binding}")?;
+        }
+
+        Ok(())
     }
 }
 
@@ -68,10 +75,11 @@ pub fn run_rules(file: &ast::ParsedFile, graph: &ScopeGraph) -> Vec<Diagnostic>
         .flat_map(|token| [run_token_rule::<UnquotedUri>(token)])
         .flatten();
 
-    let let_order_diagnostics = let_order::check(graph).into_iter().map(|range| Finding {
+    let let_order_diagnostics = let_order::check(graph).into_iter().map(|finding| Finding {
         rule_id: "let_order",
-        range,
+        range: finding.range,
         message: "Let bindings must follow dependency order",
+        binding: Some(finding.binding),
     });
 
     node_diagnostics
@@ -95,6 +103,7 @@ where
         rule_id: R::ID,
         range: node.range,
         message,
+        binding: None,
     })
 }
 
@@ -109,5 +118,6 @@ where
         rule_id: R::ID,
         range: token.range,
         message,
+        binding: None,
     })
 }
diff --git a/src/xatu/rules/let_order.rs b/src/xatu/rules/let_order.rs
index 1ea72ac..7d01ebf 100644
--- a/src/xatu/rules/let_order.rs
+++ b/src/xatu/rules/let_order.rs
@@ -3,7 +3,12 @@ use crate::{
     scope_graph::{LetScope, NodeId, ScopeGraph},
 };
 
-pub fn check(graph: &ScopeGraph) -> Vec<ast::SourceRange> {
+pub struct Finding {
+    pub range: ast::SourceRange,
+    pub binding: String,
+}
+
+pub fn check(graph: &ScopeGraph) -> Vec<Finding> {
     graph
         .let_scopes()
         .iter()
@@ -24,7 +29,10 @@ pub fn check(graph: &ScopeGraph) -> Vec<ast::SourceRange> {
                         .iter()
                         .find(|(declaration, _)| *declaration == binding.declaration)
                         .filter(|(_, expected_position)| position != *expected_position)
-                        .map(|_| binding.range)
+                        .map(|_| Finding {
+                            range: binding.range,
+                            binding: binding.name.clone(),
+                        })
                 })
         })
         .collect()
diff --git a/src/xatu/scope_graph.rs b/src/xatu/scope_graph.rs
index f9e1817..6795458 100644
--- a/src/xatu/scope_graph.rs
+++ b/src/xatu/scope_graph.rs
@@ -57,6 +57,7 @@ impl ScopeGraph {
             .iter()
             .map(|binding| Binding {
                 declaration: self.add_declaration(&binding.key.name, scope),
+                name: binding.key.name.clone(),
                 references: Vec::new(),
                 range: binding.range,
             })
@@ -187,6 +188,7 @@ pub(crate) struct LetScope {
 #[derive(Debug)]
 pub(crate) struct Binding {
     pub(crate) declaration: NodeId,
+    pub(crate) name: String,
     pub(crate) references: Vec<NodeId>,
     pub(crate) range: ast::SourceRange,
 }
diff --git a/src/xatu/xatu.rs b/src/xatu/xatu.rs
index 79f7e85..f718d89 100644
--- a/src/xatu/xatu.rs
+++ b/src/xatu/xatu.rs
@@ -26,11 +26,12 @@ impl std::fmt::Display for Report {
         for diagnostic in &self.diagnostics {
             let file = self.files.get(diagnostic.file_id);
             let (start, end) = line_range(&file.source, diagnostic.finding.range);
-            writeln!(
-                formatter,
-                "{}:{start}..{end}:{diagnostic}",
-                file.path.display()
-            )?;
+            let location = if start == end {
+                start.to_string()
+            } else {
+                format!("{start}-{end}")
+            };
+            writeln!(formatter, "{}:{location} {diagnostic}", file.path.display())?;
         }
 
         Ok(())