fix: swc upgrade - ensure const type params not removed in arrow functions (#517)

Author: dsherret

Cargo.lock

@@ -26,7 +26,7 @@ tracing = ["dprint-core/tracing"]
 
 [dependencies]
 anyhow = "1.0.64"
-deno_ast = { version = "0.25.0", features = ["view"] }
+deno_ast = { version = "0.26.0", features = ["view"] }
 dprint-core = { version = "0.60.0", features = ["formatting"] }
 rustc-hash = "1.1.0"
 serde = { version = "1.0.144", features = ["derive"] }

Cargo.toml

@@ -157,6 +157,25 @@ mod tests {
     );
   }
 
+  #[test]
+  fn it_should_error_closing_paren_missing() {
+    // issue 498
+    run_fatal_diagnostic_test(
+      "./test.ts",
+      r#"const foo = <T extends {}>() => {
+    if (bar() {
+        console.log(1);
+    }
+};"#,
+      concat!(
+        "An arrow function is not allowed here at ./test.ts:1:27\n",
+        "\n",
+        "  const foo = <T extends {}>() => {\n",
+        "                            ~~"
+      ),
+    );
+  }
+
   fn run_fatal_diagnostic_test(file_path: &str, text: &str, expected: &str) {
     let file_path = PathBuf::from(file_path);
     assert_eq!(parse_swc_ast(&file_path, text).err().unwrap().to_string(), expected);

src/swc.rs

@@ -263,3 +263,9 @@ const someFunc =
     c => {
         return a + b + c;
     };
+
+== should format with const type params ==
+const t = <const T extends 5>() => {};
+
+[expect]
+const t = <const T extends 5>() => {};

tests/specs/expressions/ArrowFunctionExpression/ArrowFunctionExpression_All.txt

@@ -69,3 +69,9 @@ const t = function(testing, this) {};
 
 [expect]
 const t = function(testing, this) {};
+
+== should format with const type params ==
+const t = function<const T extends 5>() {};
+
+[expect]
+const t = function<const T extends 5>() {};