do not raise empty-let when comments are present

Author: oppiliappan

bin/tests/data/empty_let_in.nix

@@ -1,3 +1,13 @@
-let
-in
-  null
+[
+  (
+    let
+    in
+    null
+  )
+  (
+    let
+      # don't match this, we have a comment
+    in
+    null
+  )
+]

bin/tests/snapshots/main__empty_let_in.snap

@@ -4,11 +4,11 @@ expression: "&out"
 
 ---
 [W02] Warning: Useless let-in expression
-   ╭─[data/empty_let_in.nix:1:1]
+   ╭─[data/empty_let_in.nix:3:5]
    │
- 1 │ ╭─▶ let
- 3 │ ├─▶   null
-   · │            
-   · ╰──────────── This let-in expression has no entries
+ 3 │ ╭─▶     let
+ 5 │ ├─▶     null
+   · │              
+   · ╰────────────── This let-in expression has no entries
 ───╯
 

lib/src/lints/empty_let_in.rs

@@ -1,3 +1,5 @@
+use std::ops::Not;
+
 use crate::{session::SessionInfo, Metadata, Report, Rule, Suggestion};
 
 use if_chain::if_chain;
@@ -45,6 +47,12 @@ impl Rule for EmptyLetIn {
             if inherits.count() == 0;
 
             if let Some(body) = let_in_expr.body();
+
+            // ensure that the let-in-expr does not have comments
+            if node
+                .children_with_tokens()
+                .any(|el| el.kind() == SyntaxKind::TOKEN_COMMENT)
+                .not();
             then {
                 let at = node.text_range();
                 let replacement = body;