fix(rust): handle destructured params case (#617)

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
-        vim-version: [v7.4.2119, v8.2.5172, head]
+        vim-version: [v7.4.2119, v8.2.5172, v9.0.1500]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout kkoomen/vim-doge

helper/src/rust/parser.rs

@@ -100,15 +100,19 @@ impl<'a> RustParser<'a> {
                         .for_each(|node| {
                             let mut param = Map::new();
 
-                            let func_name = node
+                            let name = node
                                 .children(&mut node.walk())
                                 .filter(|node| node.kind() == "identifier")
                                 .next()
-                                .and_then(|node| Some(self.get_node_text(&node)))
-                                .unwrap();
-                            param.insert("name".to_string(), Value::String(func_name));
+                                .and_then(|node| Some(self.get_node_text(&node)));
 
-                            params.push(Value::Object(param));
+                            if name.is_some() {
+                                param.insert("name".to_string(), Value::String(name.unwrap()));
+                            }
+
+                            if !param.is_empty() {
+                                params.push(Value::Object(param));
+                            }
                         });
 
                     if !params.is_empty() {

test/filetypes/rust/functions.vader

@@ -59,6 +59,29 @@ Expect rust (generated comments with Arguments and Examples sections):
       }
   }
 
+# ==============================================================================
+# Functions parameter destruction
+# ==============================================================================
+Given rust (function with destructured params):
+  pub fn do_thing((i, j): (u8, u8)) -> u8 {
+    i * j
+  }
+
+Do (trigger doge):
+  \<C-d>
+
+Expect rust (generated comments):
+  /// [TODO:description]
+  ///
+  /// # Examples
+  ///
+  /// ```
+  /// [TODO:write some example code]
+  /// ```
+  pub fn do_thing((i, j): (u8, u8)) -> u8 {
+    i * j
+  }
+
 # ==============================================================================
 # Functions with errors and safety section
 # ==============================================================================