From 35949a898145782b45a87fef052a4a76747f3d12 Mon Sep 17 00:00:00 2001
From: timsuchanek <tim.suchanek@gmail.com>
Date: Tue, 22 Jun 2021 16:50:17 +0200
Subject: [PATCH] Fix #51

---
 src/query/format.rs                          | 14 ++++++++------
 tests/queries/mutation_nameless_vars.graphql |  4 ++++
 tests/query_roundtrips.rs                    |  1 +
 3 files changed, 13 insertions(+), 6 deletions(-)
 create mode 100644 tests/queries/mutation_nameless_vars.graphql

diff --git a/src/query/format.rs b/src/query/format.rs
index bff4158..be78e7d 100644
--- a/src/query/format.rs
+++ b/src/query/format.rs
@@ -186,13 +186,15 @@ impl<'a, T: Text<'a>> Displayable for Mutation<'a, T>
         if let Some(ref name) = self.name {
             f.write(" ");
             f.write(name.as_ref());
-            if !self.variable_definitions.is_empty() {
-                f.write("(");
-                for var in &self.variable_definitions {
-                    var.display(f);
-                }
-                f.write(")");
+        }
+        if !self.variable_definitions.is_empty() {
+            f.write("(");
+            self.variable_definitions[0].display(f);
+            for var in &self.variable_definitions[1..] {
+                f.write(", ");
+                var.display(f);
             }
+            f.write(")");
         }
         format_directives(&self.directives, f);
         f.write(" ");
diff --git a/tests/queries/mutation_nameless_vars.graphql b/tests/queries/mutation_nameless_vars.graphql
new file mode 100644
index 0000000..bb77ebc
--- /dev/null
+++ b/tests/queries/mutation_nameless_vars.graphql
@@ -0,0 +1,4 @@
+mutation($first: Int, $second: Int) {
+  field1(first: $first)
+  field2(second: $second)
+}
diff --git a/tests/query_roundtrips.rs b/tests/query_roundtrips.rs
index 9e67da4..2eaeb1c 100644
--- a/tests/query_roundtrips.rs
+++ b/tests/query_roundtrips.rs
@@ -44,6 +44,7 @@ fn roundtrip2(filename: &str) {
 #[test] fn query_arguments() { roundtrip("query_arguments"); }
 #[test] fn query_directive() { roundtrip("query_directive"); }
 #[test] fn mutation_directive() { roundtrip("mutation_directive"); }
+#[test] fn mutation_nameless_vars() { roundtrip("mutation_nameless_vars"); }
 #[test] fn subscription_directive() { roundtrip("subscription_directive"); }
 #[test] fn string_literal() { roundtrip("string_literal"); }
 #[test] fn triple_quoted_literal() { roundtrip("triple_quoted_literal"); }