Avoid the accidental removal of comments inside expressions by dx fmt (#4410)

* Avoid the accidental removal of comments inside expressions by dx fmt

* Rewrite the logic to pass failed tests

* Removed unnecessary call to write_inline_comments

* add failing test case

* alter parsing a bit to handle more test cases

* almost there...

* fix

* use threadlocal

---------

Co-authored-by: Jonathan Kelley <jkelleyrtp@gmail.com>

packages/autofmt/src/prettier_please.rs

@@ -9,8 +9,9 @@ impl Writer<'_> {
     }
 }
 
-const MARKER: &str = "dioxus_autofmt_block__________";
-const MARKER_REPLACE: &str = "dioxus_autofmt_block__________! {}";
+// we use weird unicode alternatives to avoid conflicts with the actual rsx! macro
+const MARKER: &str = "𝕣𝕤𝕩";
+const MARKER_REPLACE: &str = "𝕣𝕤𝕩! {}";
 
 pub fn unparse_expr(expr: &Expr, src: &str, cfg: &IndentOptions) -> String {
     struct ReplaceMacros<'a> {
@@ -42,7 +43,6 @@ pub fn unparse_expr(expr: &Expr, src: &str, cfg: &IndentOptions) -> String {
                 }
                 .unwrap();
 
-                // always push out the rsx to require a new line
                 i.path = syn::parse_str(MARKER).unwrap();
                 i.tokens = Default::default();
 
@@ -84,7 +84,7 @@ pub fn unparse_expr(expr: &Expr, src: &str, cfg: &IndentOptions) -> String {
 
     // now we can replace the macros with the formatted blocks
     for fmted in replacer.formatted_stack.drain(..) {
-        let is_multiline = fmted.contains('{');
+        let is_multiline = fmted.ends_with('}') || fmted.contains('\n');
         let is_empty = fmted.trim().is_empty();
 
         let mut out_fmt = String::from("rsx! {");