feat(natu): lint redundant parameter forwarding

src/natu/natu_test.rs

@@ -101,6 +101,64 @@ entry
     Ok(())
 }
 
+#[gtest]
+fn natu_reports_redundant_parameter_forwarding() -> googletest::Result<()> {
+    let report = natu::future_sight(vec![
+        SourceFile {
+            path: PathBuf::from("testdata/attribute_parameter.nix"),
+            source: r#"
+{ hosts, ... }:
+let
+  collect = { hosts }: hosts;
+in
+collect { inherit hosts; }
+"#
+            .into(),
+        },
+        SourceFile {
+            path: PathBuf::from("testdata/plain_parameter.nix"),
+            source: r#"
+value:
+let
+  transform = value: value;
+in
+transform value
+"#
+            .into(),
+        },
+        SourceFile {
+            path: PathBuf::from("testdata/curried_parameter.nix"),
+            source: r#"
+{ hosts, ... }:
+let
+  transform = prefix: hosts: suffix: hosts;
+in
+transform "prefix" hosts "suffix"
+"#
+            .into(),
+        },
+        SourceFile {
+            path: PathBuf::from("testdata/local_parameter.nix"),
+            source: r#"
+let
+  transform = value: value;
+in
+transform value
+"#
+            .into(),
+        },
+    ])
+    .or_fail()?;
+
+    let count = report
+        .diagnostics
+        .iter()
+        .filter(|diagnostic| diagnostic.finding.rule_id == "redundant_parameter_forwarding")
+        .count();
+    expect_that!(count, eq(3));
+    Ok(())
+}
+
 #[gtest]
 fn natu_reports_list_to_attrs_after_map() -> googletest::Result<()> {
     let report = natu::future_sight(vec![SourceFile {