feat(natu): support preceding suppressions

src/dotfiles/default.nix

@@ -22,6 +22,8 @@ let
     root = root + "/registry";
   };
 
+  # TODO: Refactor guest-module composition.
+  # NOLINT(single_use_binding)
   guestModules = import ./guests.nix {
     inherit
       inputs

src/natu/natu_test.rs

@@ -77,6 +77,27 @@ fn natu_preserves_suppressed_bindings() -> googletest::Result<()> {
     Ok(())
 }
 
+#[gtest]
+fn natu_preserves_preceding_suppressed_binding() -> googletest::Result<()> {
+    let report = natu::future_sight(vec![SourceFile {
+        path: PathBuf::from("testdata/preceding_nolint.nix"),
+        source: r#"
+let
+  # NOLINT(single_use_binding)
+  value = {
+    nested = true;
+  };
+in
+value
+"#
+        .into(),
+    }])
+    .or_fail()?;
+
+    expect_that!(report.is_clean(), is_true());
+    Ok(())
+}
+
 #[gtest]
 fn natu_reports_select_dependency_order() -> googletest::Result<()> {
     let report = natu::future_sight(vec![SourceFile {

src/natu/rules.rs

@@ -127,6 +127,18 @@ pub fn run_rules(file: &ast::ParsedFile, graph: &ScopeGraph, source: &str) -> Ve
 
 pub fn is_suppressed(source: &str, range: ast::SourceRange, rule_id: &str) -> bool {
     let line = source[range.start..].lines().next().unwrap_or_default();
+    line_suppresses(line, rule_id) || preceding_line_suppresses(source, range, rule_id)
+}
+
+fn preceding_line_suppresses(source: &str, range: ast::SourceRange, rule_id: &str) -> bool {
+    let Some((preceding_source, _current_line)) = source[..range.start].rsplit_once('\n') else {
+        return false;
+    };
+    let preceding_line = preceding_source.lines().next_back().unwrap_or_default();
+    line_suppresses(preceding_line, rule_id)
+}
+
+fn line_suppresses(line: &str, rule_id: &str) -> bool {
     let Some(comment) = line.split_once('#').map(|(_, comment)| comment.trim()) else {
         return false;
     };