Make the SnakeCase formatter not emit additional _

vadixidav · Nov 26, 2018 · 5a9c8b1 · 5a9c8b1
1 parent 57f7ec2
commit 5a9c8b1
Showing 1 changed file with 17 additions and 2 deletions.
diff --git a/src/bindgen/rename.rs b/src/bindgen/rename.rs
@@ -65,10 +65,25 @@ impl RenameRule {
             RenameRule::PascalCase => text.to_owned(),
             RenameRule::CamelCase => text[..1].to_lowercase() + &text[1..],
             RenameRule::SnakeCase => {
+                // Do not add additional `_` if the string already contains `_` e.g. `__Field`
+                // Do not split consecutive capital letters
                 let mut result = String::new();
+                let mut add_separator = true;
+                let mut prev_uppercase = false;
                 for (i, c) in text.char_indices() {
-                    if c.is_uppercase() && i != 0 {
-                        result.push_str("_");
+                    if c == '_' {
+                        add_separator = false;
+                        prev_uppercase = false;
+                    }
+                    if c.is_uppercase() {
+                        if i != 0 && add_separator && !prev_uppercase {
+                            result.push_str("_");
+                        } else {
+                            add_separator = true;
+                        }
+                        prev_uppercase = true;
+                    } else {
+                        prev_uppercase = false;
                     }
                     for x in c.to_lowercase() {
                         result.push(x);