Combine the test suites

testing/tests/compile-fail/duplicate-attribute/rename-and-ser.rs

@@ -0,0 +1,10 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename="x", serialize="y")] //~^^ HELP: unknown serde field attribute `serialize`
+    x: (),
+}
+
+fn main() {}

testing/tests/compile-fail/duplicate-attribute/rename-rename-de.rs

@@ -0,0 +1,11 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename="x")]
+    #[serde(rename(deserialize="y"))] //~^^^ HELP: duplicate serde attribute `rename`
+    x: (),
+}
+
+fn main() {}

testing/tests/compile-fail/duplicate-attribute/rename-ser-rename-ser.rs

@@ -0,0 +1,10 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename(serialize="x"), rename(serialize="y"))] //~^^ HELP: duplicate serde attribute `rename`
+    x: (),
+}
+
+fn main() {}

testing/tests/compile-fail/duplicate-attribute/rename-ser-rename.rs

@@ -0,0 +1,11 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename(serialize="x"))]
+    #[serde(rename="y")] //~^^^ HELP: duplicate serde attribute `rename`
+    x: (),
+}
+
+fn main() {}

testing/tests/compile-fail/duplicate-attribute/rename-ser-ser.rs

@@ -0,0 +1,10 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename(serialize="x", serialize="y"))] //~^^ HELP: duplicate serde attribute `rename`
+    x: (),
+}
+
+fn main() {}

testing/tests/compile-fail/duplicate-attribute/two-rename-ser.rs

@@ -0,0 +1,11 @@
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: custom derive attribute panicked
+struct S {
+    #[serde(rename(serialize="x"))]
+    #[serde(rename(serialize="y"))] //~^^^ HELP: duplicate serde attribute `rename`
+    x: (),
+}
+
+fn main() {}