From 1d5c4b0a143e02980fcfa1b6d6d3bee63a4d3ebf Mon Sep 17 00:00:00 2001
From: konsti <konstin@mailbox.org>
Date: Fri, 8 Sep 2023 11:25:06 +0200
Subject: [PATCH] Show header for formatter comment decoration info (#7228)

Show header for formatter comment decoration info

**Summary** Show a header in the formatter comment decoration debug
output that shows which node is preceding/following/enclosing
(https://github.com/astral-sh/ruff/pull/6813#issuecomment-1708119550). I
kept this intentionally condensed to make it easy to use this is a small
sidebar without vertical scrolling.

```console
$ cargo run --bin ruff_python_formatter -- --emit stdout --print-comments scratch.py
# Comment decoration: Range, Preceding, Following, Enclosing, Comment
17..20, Some((ParameterWithDefault, 6..10)), None, (Parameters, 5..22), "# a"
44..47, Some((StmtExpr, 28..39)), Some((StmtExpr, 52..60)), (StmtFunctionDef, 0..60), "# b"
77..80, None, None, (ExprList, 71..82), "# c"
{
    Node {
        kind: ParameterWithDefault,
        range: 6..10,
        source: `x=[]`,
    }: {
...
```

**Test Plan** It's debug output.
---
 crates/ruff_python_formatter/src/cli.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/crates/ruff_python_formatter/src/cli.rs b/crates/ruff_python_formatter/src/cli.rs
index b1c1d2b1d2..6b79bacdbd 100644
--- a/crates/ruff_python_formatter/src/cli.rs
+++ b/crates/ruff_python_formatter/src/cli.rs
@@ -69,9 +69,12 @@ pub fn format_and_debug_print(input: &str, cli: &Cli, source_type: &Path) -> Res
         // Print preceding, following and enclosing nodes
         let source_code = SourceCode::new(input);
         let decorated_comments = collect_comments(&python_ast, source_code, &comment_ranges);
+        if !decorated_comments.is_empty() {
+            println!("# Comment decoration: Range, Preceding, Following, Enclosing, Comment");
+        }
         for comment in decorated_comments {
             println!(
-                "{:?} {:?} {:?} {:?} {:?}",
+                "{:?}, {:?}, {:?}, {:?}, {:?}",
                 comment.slice().range(),
                 comment
                     .preceding_node()