Changes per reviewer comments

Author: davidBar-On

src/macros.rs

@@ -1220,10 +1220,13 @@ impl MacroBranch {
 
         // 5 = " => {"
         let old_body = context.snippet(self.body).trim();
-        let prefix_width = 5 + if context.config.format_macro_bodies() {
-            old_body.find(|ch| ch != '{').unwrap_or(old_body.len()) // " => {{..."
+        let has_block_body = old_body.starts_with('{');
+        let prefix_width = if has_block_body && context.config.format_macro_bodies() {
+            // 6 = " => {{"
+            6
         } else {
-            0
+            // 5 = " => {"
+            5
         };
         let mut result =
             format_macro_args(context, self.args.clone(), shape.sub_width(prefix_width)?)?;
@@ -1245,7 +1248,6 @@ impl MacroBranch {
         // variables for new names with the same length first.
 
         let (body_str, substs) = replace_names(old_body)?;
-        let has_block_body = old_body.starts_with('{');
 
         let mut config = context.config.clone();
         config.set().hide_parse_errors(true);

tests/source/issue-3805.rs

@@ -7,6 +7,27 @@ return;
 }};
 }
 
+// Spaces between the `{` and `}`
+macro_rules! test {
+($aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr) => {     {
+return;
+}      };
+}
+
+// Multi  `{}`
+macro_rules! test {
+($aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr) => {{{{
+return;
+}}}};
+}
+
+// Multi  `{}` with spaces
+macro_rules! test {
+($aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr) => {    {    {    {
+return;
+}     }     }    };
+}
+    
 // Line length 102
 macro_rules! test {
 ($aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeiou:expr, $add:expr) => {{

tests/target/issue-3805.rs

@@ -9,6 +9,41 @@ macro_rules! test {
     }};
 }
 
+// Spaces between the `{` and `}`
+macro_rules! test {
+    (
+        $aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr
+    ) => {{
+        return;
+    }};
+}
+
+// Multi  `{}`
+macro_rules! test {
+    (
+        $aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr
+    ) => {{
+        {
+            {
+                return;
+            }
+        }
+    }};
+}
+
+// Multi  `{}` with spaces
+macro_rules! test {
+    (
+        $aasdfghj:expr, $qwertyuiop:expr, $zxcvbnmasdfghjkl:expr, $aeiouaeiouaeio:expr, $add:expr
+    ) => {{
+        {
+            {
+                return;
+            }
+        }
+    }};
+}
+
 // Line length 102
 macro_rules! test {
     (