Support comments on attributes (#5850)

Signed-off-by: Nick Cameron <nrc@ncameron.org>

rust/kcl-lib/src/unparser.rs

@@ -23,19 +23,31 @@ impl Program {
             .map(|sh| format!("{}\n\n", sh.inner.content))
             .unwrap_or_default();
 
-        for attr in &self.inner_attrs {
-            result.push_str(&attr.recast(options, indentation_level));
-        }
         for start in &self.non_code_meta.start_nodes {
             result.push_str(&start.recast(options, indentation_level));
         }
-        let result = result; // Remove mutation.
+        for attr in &self.inner_attrs {
+            result.push_str(&attr.recast(options, indentation_level));
+        }
+        if !self.inner_attrs.is_empty() {
+            result.push('\n');
+        }
 
+        let result = result; // Remove mutation.
         let result = self
             .body
             .iter()
             .map(|body_item| {
                 let mut result = String::new();
+                for comment in body_item.get_comments() {
+                    if !comment.is_empty() {
+                        result.push_str(&indentation);
+                        result.push_str(comment);
+                    }
+                    if !result.ends_with("\n\n") && result != "\n" {
+                        result.push('\n');
+                    }
+                }
                 for attr in body_item.get_attrs() {
                     result.push_str(&attr.recast(options, indentation_level));
                 }
@@ -173,7 +185,18 @@ impl Node<NonCodeNode> {
 
 impl Node<Annotation> {
     fn recast(&self, options: &FormatOptions, indentation_level: usize) -> String {
-        let mut result = "@".to_owned();
+        let indentation = options.get_indentation(indentation_level);
+        let mut result = String::new();
+        for comment in &self.pre_comments {
+            if !comment.is_empty() {
+                result.push_str(&indentation);
+                result.push_str(comment);
+            }
+            if !comment.ends_with("*/") && !result.ends_with("\n\n") && result != "\n" {
+                result.push('\n');
+            }
+        }
+        result.push('@');
         if let Some(name) = &self.name {
             result.push_str(&name.name);
         }
@@ -956,6 +979,7 @@ mod tests {
     fn test_recast_annotations_in_function_body() {
         let input = r#"fn myFunc() {
   @meta(yes = true)
+
   x = 2
 }
 "#;
@@ -975,6 +999,25 @@ mod tests {
         assert_eq!(output, input);
     }
 
+    #[test]
+    fn recast_annotations_with_comments() {
+        let input = r#"// Start comment
+
+// Comment on attr
+@settings(defaultLengthUnit = in)
+
+// Comment on item
+foo = 42
+
+// Comment on another item
+@(impl = kcl)
+bar = 0
+"#;
+        let program = crate::parsing::top_level_parse(input).unwrap();
+        let output = program.recast(&Default::default(), 0);
+        assert_eq!(output, input);
+    }
+
     #[test]
     fn test_recast_if_else_if_same() {
         let input = r#"b = if false {
@@ -1241,7 +1284,6 @@ outsideRevolve = startSketchOn('XZ')
             r#"// Ball Bearing
 // A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The primary purpose of a ball bearing is to reduce rotational friction and support radial and axial loads.
 
-
 // Define constants like ball diameter, inside diameter, overhange length, and thickness
 sphereDia = 0.5
 insideDia = 1
@@ -1643,6 +1685,7 @@ tabs_l = startSketchOn({
         assert_eq!(
             recasted,
             r#"@settings(units = mm)
+
 // define nts
 radius = 6.0
 width = 144.0
@@ -2633,4 +2676,35 @@ sketch002 = startSketchOn({
             );
         }
     }
+
+    #[test]
+    fn code_with_comment_and_extra_lines() {
+        let code = r#"yo = 'c'
+
+/* this is
+a
+comment */
+yo = 'bing'
+"#;
+        let ast = crate::parsing::top_level_parse(code).unwrap();
+        let recasted = ast.recast(&FormatOptions::new(), 0);
+        assert_eq!(recasted, code);
+    }
+
+    #[test]
+    fn comments_in_a_fn_block() {
+        let code = r#"fn myFn() {
+  // this is a comment
+  yo = { a = { b = { c = '123' } } }
+
+  /* block
+  comment */
+  key = 'c'
+  // this is also a comment
+}
+"#;
+        let ast = crate::parsing::top_level_parse(code).unwrap();
+        let recasted = ast.recast(&FormatOptions::new(), 0);
+        assert_eq!(recasted, code);
+    }
 }